[Show abstract][Hide abstract] ABSTRACT: Metal often causes delayed-type hypersensitivity reactions, which are possibly mediated by accumulating T cells in the inflamed skin, called irritant or allergic contact dermatitis. However, accumulating T cells during development of a metal allergy are poorly characterized because a suitable animal model is unavailable. We have previously established novel murine models of metal allergy and found accumulation of both metal-specific T cells and natural killer (NK) T cells in the inflamed skin. In our novel models of metal allergy, skin hypersensitivity responses were induced through repeated sensitizations by administration of metal chloride and lipopolysaccharide into the mouse groin followed by metal chloride challenge in the footpad. These models enabled us to investigate the precise mechanisms of the immune responses of metal allergy in the inflamed skin. In this review, we summarize the immune responses in several murine models of metal allergy and describe which antigen-specific responses occur in the inflamed skin during allergic contact dermatitis in terms of the T cell receptor. In addition, we consider the immune regulation of accumulated NK T cells in metal ion-induced allergic contact dermatitis.
Preview · Article · Jan 2016 · International Journal of Molecular Sciences
[Show abstract][Hide abstract] ABSTRACT: Poly(ADP-ribosyl)ation is known to be involved in a variety of cellular processes, such as DNA repair, cell death, telomere regulation, genomic stability and cell differentiation by poly(ADP-ribose) polymerase (PARP). While PARP inhibitors are presently under clinical investigation for cancer therapy, little is known about their side effects. However, PARP involvement in mesenchymal stem cell (MSC) differentiation potentiates MSC-related side effects arising from PARP inhibition. In this study, effects of PARP inhibitors on MSCs were examined. MSCs demonstrated suppressed osteogenic differentiation after 1 µM PJ34 treatment without cytotoxicity, while differentiation of MSCs into chondrocytes or adipocytes was unaffected. PJ34 suppressed mRNA induction of osteogenic markers, such as Runx2, Osterix, Bone Morphogenetic Protein-2, Osteocalcin, bone sialoprotein, and Osteopontin, and protein levels of Bone Morphogenetic Protein-2, Osterix and Osteocalcin. PJ34 treatment also inhibited transcription factor regulators such as Smad1, Smad4, Smad5 and Smad8. Extracellular mineralized matrix formation was also diminished. These results strongly suggest that PARP inhibitors are capable of suppressing osteogenic differentiation and poly(ADP-ribosyl)ation may play a physiological role in this process through regulation of BMP-2 signaling. Therefore, PARP inhibition may potentially attenuate osteogenic metabolism, implicating cautious use of PARP inhibitors for cancer treatments and monitoring of patient bone metabolism levels.
Full-text · Article · Oct 2015 · International Journal of Molecular Sciences
[Show abstract][Hide abstract] ABSTRACT: Central odontogenic fibroma (COF) is a rare odontogenic tumor, the primary treatment of which is tumor ablation with extraction of related teeth. We report a case of COF that developed in the left maxilla in a 24-year-old woman. There were no subjective symptoms, however, she had noticed malposition of the second premolar to the palatal side and slight swelling of the buccal gingiva around the tooth since nine years old. The swelling had recently become larger, and she was referred to our clinic. A biopsy of the lesion showed a histological diagnosis of COF. CT images revealed resorption of the alveolar bone around the tumor, and expansion to the roots of the premolars and first molar. Reconstruction of the alveolar ridge using iliac particulate cancellous bone and marrow was carried out immediately after tumor ablation with extraction of the premolars and first molar. Five months later, there was no evidence suggesting tumor recurrence, and alveolar ridge augmentation was clearly apparent on CT images. The serial dental implant treatment was thus completed. The occlusion was restored by an implant prosthesis, and no evidence of tumor recurrence was found during four years of follow-up.
[Show abstract][Hide abstract] ABSTRACT: This is the first report to our knowledge of an intramuscular lipoma that arose in the masseter muscle. Excision biopsy under general anaesthesia showed that the mass could easily be separated from the surrounding soft tissues on the lateral side, but was firmly adherent to the muscle on the medial side, so complete excision required resection of part of the masseter. Histopathological examination showed that it was an intramuscular lipoma. Two years and 6 months postoperatively there was no evidence of recurrence.
No preview · Article · Apr 2014 · British Journal of Oral and Maxillofacial Surgery
[Show abstract][Hide abstract] ABSTRACT: Myofibroma is a benign tumor composed of myoid spindle cells. The prevalence of myofibroma in the oral cavity is very low, with the mandible being the most common site. This report describes an adult case of myofibroma that arose on the mandible and includes magnetic resonance imaging (MRI) and positron emission tomography (PET) findings. On the MRI T1-weighted images, the tumor appeared with signal iso-intensity and was highly and heterogeneously enhanced with contrast material. On the T2-weighted images, it appeared with increased signal intensity. 18 F-fluorodeoxyglucose (FDG)-PET imaging showed abnormal strong accumulation of FDG in the left mandibular region. The tumor was removed by marginal resection of the left mandible under general anesthesia. Histopathological findings revealed that the tumor stroma contained abundant thin-walled vessels. The postoperative course was uneventful, and we found no evidence of recurrence at the postoperative 34-month follow-up.
Full-text · Article · Mar 2014 · World Journal of Surgical Oncology
[Show abstract][Hide abstract] ABSTRACT: In this paper, we report the clinical course of a 11-year-old boy with an ameloblastic fibrodentinoma developing in the right side of the mandible. Clinically, there were no specific findings, except for an unerupted right mandibular first molar. Panoramic radiography and dental computed tomography revealed a well-defined radiolucent lesion with small calcified particles in the right side of the mandible. Moreover, an impacted tooth, which appeared to be the unerupted first molar, existed below the radiolucent lesion. A biopsy was performed, and the lesion was histopathologically diagnosed as ameloblastic fibrodentinoma. The tumor was removed with preservation of the impacted tooth under general anesthesia. As of 3 years after surgery, there have been no signs of recurrence, and the impacted tooth has erupted spontaneously in the dentition and functions as the first molar.
Preview · Article · Jan 2014 · Nippon Koku Geka Gakkai zasshi
[Show abstract][Hide abstract] ABSTRACT: Abstract The objective of this study is to evaluate usefulness of mandibular reconstructions using a custom-made titanium mesh (Ti-mesh) tray and particulate cancellous bone and marrow (PCBM). A consecutive nine patients who underwent mandibular reconstruction were enrolled in this study. They were five men and four women (mean age: 53.9 years). Virtual reality simulation was performed using computer software based on the pre-operative computed tomography data. A 3-dimensional (3-D) skull model was constructed using a 3-D printer. A tray was custom-made from a Ti-mesh sheet bent to adapt to the model. After PCBM harvesting from bilateral posterior ilia, the tray was fixed to the host bone. New bone formation and configuration of the reconstructed mandible were assessed radiologically. Complications were recorded in each patient during the follow-up period. Patients, satisfaction with post-operative facial contour was evaluated using a visual analogue scale (VAS score, range = 0-100). In six of nine patients, excellent new bone formation was recognised and expected results were radiologically achieved. Complications occurred in four patients. These complications included Ti-mesh fracture, Ti-mesh exposure in the oral cavity, and delayed infection. Mean VAS score on patient satisfaction was 77.6. Although the data are preliminary, the results suggest that this method is clinically useful.
[Show abstract][Hide abstract] ABSTRACT: Objective:
This study aimed to establish a mouse model in which dental pulp cells (DPCs) could be used as a cell source for the treatment of salivary gland hypofunction.
DPCs were isolated from green fluorescent protein (GFP)-expressing mice and were differentiated into dental pulp endothelial cells (DPECs). DPEC behaviour was studied in vitro and in vivo to investigate their capacity to participate in neovascularisation. For in vivo assessment, a combination of DPECs and Matrigel was subcutaneously injected into nude mice. Two weeks after injection, Matrigel plugs were analysed for CD31 and GFP. Furthermore, both submandibular glands of the irradiated mice were injected with DPECs. Eight weeks after irradiation, the effect of DPECs on saliva secretion was evaluated by measuring amounts of saliva secretion.
DPECs showed typical endothelial morphology, including a cobblestone appearance. RT-PCR analysis of DPECs showed positive expression of CD31, foetal liver kinase-1, vascular-endothelial-cadherin, vascular endothelial growth factor-A and von Willebrand factor. DPECs reorganised into tube-like structures on Matrigel after 24h in vitro. Positive merged staining for both CD31 and GFP was observed in the tube-like structures, representative of the injected DPECs. The average saliva flow rate in mice treated with DPECs was significantly higher than that observed in mice treated with PBS (P=0.0452).
Our results show that radiation-induced salivary hypofunction is partially reverted following transplantation of DPECs. We established a mouse model in which DPCs could be used as a cell source for the treatment of salivary gland hypofunction.
[Show abstract][Hide abstract] ABSTRACT: In the present study, we investigate the expression profile of the epidermal growth factor receptor family, which comprises EGFR/ErbB1, HER2/ErbB2, HER3/ErbB3 and HER4/ErbB4 in oral leukoplakia (LP). The expression of four epidermal growth factor receptor (EGFR) family genes and their ligands were measured in LP tissues from 14 patients and compared with levels in 10 patients with oral lichen planus (OLP) and normal oral mucosa (NOM) from 14 healthy donors by real-time polymerase chain reaction (PCR) and immunohistochemistry. Synchronous mRNA coexpression of ErbB1, ErbB2, ErbB3 and ErbB4 was detected in LP lesions. Out of the receptors, only ErbB4 mRNA and protein was more highly expressed in LP compared with NOM tissues. These were strongly expressed by epithelial keratinocytes in LP lesions, as shown by immunohistochemistry. Regarding the ligands, the mRNA of Neuregulin2 and 4 were more highly expressed in OLP compared with NOM tissues. Therefore, enhanced ErbB4 on the keratinocytes and synchronous modulation of EGFR family genes may contribute to the pathogenesis and carcinogenesis of LP.International Journal of Oral Science (2013) 5, doi:10.1038/ijos.2013.10; published online 15 March 2013.
Full-text · Article · Mar 2013 · International Journal of Oral Science
[Show abstract][Hide abstract] ABSTRACT: This case report presents an unusual case of a simple mandibular bone cyst with remarkable tooth resorption. A 52-year-old woman was referred to our clinic for examination of a radiolucent lesion located in the right third mandibular molar region. The lesion could not be identified on panoramic radiograph at 6 years ago. Imaging examinations demonstrated a relatively well demarcated radiolucent lesion in the right mandible with marked resorption of the third molar. Based on the tentative diagnosis of an intraosseous benign tumor, biopsy was performed. The lesion was a simple bone cavity containing sanguineous fluid with no evidences of a cystwall lining or tumoral tissue. Intraoperative diagnosis was a simple bone cyst, and the lesion including the remained third molar was carefully removed. Histopathologically, thin fibrous connective tissue without epithelial cover was observed on the surface of the bony wall. The histopathologic findings were consistent with those of a simple bone cyst. However, myxofibromatous connective tissue and woven bone were observed only on the surface of the resorbed dental hard tissue. This case may be associated with the fibro-osseous lesion to some degree. One year later, complete healing was observed.
[Show abstract][Hide abstract] ABSTRACT: This paper introduces the mandibular reconstruction using a custom-made titanium mesh (Ti-mesh) tray and autogenous particulate cancellous bone and marrow (PCBM), with a representative case report. The Ti-mesh tray is accurately adapted to the mandibular defect and its configuration is suitable for reproducing the final dental occlusion in each patient by utilizing computer-aided design/computer-aided manufacture (CAD/CAM) and dental laboratory technology. Eleven patients with mandibular defects (9 segmental defects and 2 marginal defects) underwent the present mandibular reconstruction. All reconstructive surgeries were successful and postoperative facial contour was acceptable for most patients. Although fracture of the Ti-mesh tray was recognized within 3 months after surgery in 2 patients with mandibular defect including the mentum area, we carried out successful additional reconstructive surgeries using a reinforced Ti-mesh tray and PCBM in these 2 patients. Although the present mandibular reconstruction requires several improvements, it seems to be clinically more predictive than the conventional mandibular reconstruction.
No preview · Article · Jan 2013 · Japanese Journal of Head and Neck Cancer
[Show abstract][Hide abstract] ABSTRACT: We report a case of inflammatory pseudotumor arising in the mandible that was difficult to differentially diagnoses.A 56 -year-old man visited our clinic because of gingival swelling of the left side of the mandible. Perimandibular inflammation was diagnosed, and the patient underwent incisional drainage and received antibiotics and non-steroidal anti-inflammatory drugs. Transient remission was obtained. Subsequently, however, the gingival swelling rapidly increased, and the left mandibular lateral incisor and second premolar fell out. In additoin, paresthesia of the mental nerve appeared. Although a biopsy suggested that the lesion was an inflammatory pseudotumor, coexistence of a malignant tumor could not be clinically ruled out. Therefore, we decided to perform marginal resection of the left side of the mandible. However, we performed an excisional biopsy because progressive growth of the lesion had gradually subsided. The specimen was consistent with osteomyelitis. The surgical wound healed uneventfully, and no evidence of recurrence has been detected for more than 1 year. Finally, the present case was diagnosed as an inflammatory pseudotumor accompanied by acute mandibular osteomyelitis.
No preview · Article · Jan 2013 · Nippon Koku Geka Gakkai zasshi
[Show abstract][Hide abstract] ABSTRACT: Stem cell-based therapy has been proposed as a promising strategy for regenerating tissues lost through incurable diseases. Side population (SP) cells have been identified as putative stem cells in various organs. To examine therapeutic potential of SP cells in hypofunction of exocrine glands, SP cells isolated from mouse exocrine glands, namely, lacrimal and salivary glands, were transplanted into mice with irradiation-induced hypofunction of the respective glands. The secretions from both glands in the recipient mice were restored within 2 months of transplantation, although the transplanted cells were only sparsely distributed and produced no outgrowths. Consistent with this, most SP cells were shown to be CD31-positive endothelial-like cells. In addition, we clarified that endothelial cell-derived clusterin, a secretory protein, was an essential factor for SP cell-mediated recovery of the hypofunctioning glands because SP cells isolated from salivary glands of clusterin-deficient mice had no therapeutic potential, whereas lentiviral transduction of clusterin restored the hypofunction. In vitro and in vivo studies showed that clusterin had an ability to directly inhibit oxidative stress and oxidative stress-induced cell damage. Thus, endothelial cell-derived clusterin possibly inhibit oxidative stress-induced hypofunction of these glands.
[Show abstract][Hide abstract] ABSTRACT: Solitary fibrous tumor (SFT) is an uncommon spindle-cell mesenchymal tumor of probable fibroblastic derivation that most often occurs in the pleura, where it is typically benign. This report describes a case of a large SFT that arose in the buccal space, and includes computerized tomography, magnetic resonance imaging, and positron emission tomography (PET) findings. (18)F-Fluorodeoxyglucose (FDG) PET axial imaging showed weak abnormal accumulation of FDG in the left buccal region. The tumor was located behind the posterior wall of the maxilla, adjacent to the medial aspect of the coronoid process and was compressed between the coronoid and maxillary alveolar processes. We resected it with the use of a transoral approach in combination with coronoidectomy. Coronoidectomy was chosen because it facilitated safe removal of the tumor by improving its visibility and providing enough working space to resect it through a transoral approach.
[Show abstract][Hide abstract] ABSTRACT: The purpose of this study was to investigate the effect of stereotactic radiosurgery on local control and organ preservation in cases of primary head and neck cancer.
In this retrospective study, 14 patients with a mean age of 73 years were treated between March 2006 and September 2007 with stereotactic radiosurgery for the management of primary head and neck cancer. The patients had biopsy confirmation of disease before treatment and all patients were confirmed with squamous cell carcinoma. The staging consisted of T2 (5 cases), T3 (3 cases), T4 (6 cases), N0 (13 cases), and N1 (1 case). Marginal doses were 3,500 to 4,200 cGy in 3 or 5 fractions. The outcome was assessed according to Response Evaluation Criteria in Solid Tumors criteria based on magnetic resonance imaging and positron emission tomography/computed tomography.
Significant tumor reduction was noted at the third month of follow-up with 5 complete responses and 9 partial responses. At a mean follow-up of 36 months (range, 14-40 mo) the local control and overall survival rates were 71.4% (10/14) and 78.6% (11/14), respectively.
These results show the feasibility of using stereotactic radiosurgery for primary head and neck cancer and its potential benefit in local control and organ preservation.
No preview · Article · Jul 2011 · Journal of oral and maxillofacial surgery: official journal of the American Association of Oral and Maxillofacial Surgeons
[Show abstract][Hide abstract] ABSTRACT: This study aimed to investigate the roles of the epidermal growth factor receptor (EGFR) family members and their ligands in oral lichen planus (OLP).
The expressions of 4 EGFR-like receptors and 6 EGF-like ligands were measured in OLP tissues from 10 patients and compared with the levels in normal oral mucosa (NOM) from 10 healthy donors.
Of the receptors, only EGFR mRNA and protein were more highly expressed in OLP compared with NOM tissues. Regarding the ligands, the mRNAs of amphiregulin (AREG), epiregulin (EREG), and heparin-binding EGF-like growth factor (HB-EGF) were more highly expressed in OLP compared with NOM tissues. These ligands were strongly expressed by infiltrating lamina propria lymphocytes as well as epithelial keratinocytes in OLP lesions, as shown by immunohistochemistry.
The enhanced EGFR expression on the keratinocytes in OLP lesions and the up-regulation of EGF-like ligands in keratinocytes and infiltrating mononuclear cells could contribute to the carcinogenesis and pathogenesis of OLP.
No preview · Article · Oct 2010 · Oral Surgery, Oral Medicine, Oral Pathology, Oral Radiology, and Endodontology