Teruhiko Ishii

Immunoelectron microscopic studies of glycosaminoglycans in the metaphyseal bone trabeculae of growing rats

SummaryThe types and distribution of glycosaminoglycans (GAGs) were studied immunocytochemically in osteoid, mineralized bone matrix, and cartilage matrix of growing rat metaphyseal bone after aldehyde fixation and EDTA demineralization, using four monoclonal antibodies (mAbs 1-B-5, 2-B-6, 3-B-3 and 5-D-4). These mAbs specifically recognize epitopes in non-sulphated chondroitin (C0-S); chondroitin 4-sulphate (C4-S) and dermatan sulphate (DS); chondroitin 6-sulphate (C6-S) and C0-S; and keratan sulphate (KS) respectively. In osteoid, all mAbs except 1-B-5 weakly stained matrix material on and between collagen fibrils, and moderately stained organic material corresponding to bone nodules, which are known sites of mineralization. However, the staining of osteoid abruptly decreased at the mineralization front; weak staining was confined mostly to the organic material of bone nodules in mineralized bone matrix, with very weak or no staining of the rest of the bone matrix. This staining progressively decreased toward the mineralized cartilage matrix and became negative. The mineralized cartilage matrix and lamina limitans reacted strongly with all mAbs except 5-D-4. These results indicate that osteoid contains sulphated proteoglycans containing C4-S and/or DS, C6-S and KS, and subsequent bone matrix mineralization appears to require accumulation of these macromolecules within bone nodules and eventual loss of these substances for complete mineralization, whereas proteoglycans containing C0-S, C4-S and/or DS, and C6-S, still exist in mineralized cartilage matrix and lamina limitants.

Three-dimensional reconstruction of a fibro-osseous lesion using binary images transformed from histopathological images

The aim of this report was to introduce a new method of three-dimensional (3D) reconstruction for fibro-osseous lesions (FOLs) using binary images transformed from histopathological images and to describe its usefulness. A sample of multiconfluent FOL was used (one of the five types of FOL according to a radiographic classification) which was diagnosed histopathologically as ossifying fibroma. Approximately 30 pathological images were assembled into a composite image of the slide using Tiling Boutique software version 3 for Windows (Sanyo Electric, Osaka, Japan). The tiling images were transformed into 8-bit scale images and then into binary images using ImageJ software ver.1.37 (National Institutes of Health, Bethesda, MD). These images were used for 3D reconstruction using ImageJ software. Images were loaded at the same matrix size and were reconstructed into layers of two-dimensional image stacks, adjusted so that contiguous images were aligned based on their centre points, and arranged with long axes horizontal. 3D findings aided the visual understanding of morphological features in the lesion. The 3D reconstruction can be displayed with arbitrary rotation. In this case, the 3D reconstruction, using Real Image software version 4.01 for Windows (KGT, Tokyo, Japan), was created from an arbitrary section. This allowed us to determine the pattern of calcification between groups of connected osteoids and to compare the internal structure of such lesions that are not visible on histopathological findings. Differentiation of features was even more pronounced with a two colour display indicating fibrous connective tissue and osteoid tissue. A 3D reconstruction of a multiconfluent ossifying fibroma was created using binary images transformed from histopathological images. The quality of the images depends above all on the functionality of the image-processing software. Comparison of each pattern of FOL might allow more simple assessment of the morphological features of FOLs.

Ameloblastoma, desmoplastic type: a case report with characteristic radiological presentation

Ameloblastoma, desmoplastic type, is a rare lesion for which radiographic images are even less common, and such lesions are sometimes considered to be variant types. It is defined as a variant of ameloblastoma with specific imaging and histological features. This lesion occurs with the same frequency in the maxilla and mandible, although the predominant site is the anterior-premolar site in both the mandible and maxilla. For our case of ameloblastoma, desmoplastic type, resected from the right anterior to premolar maxilla, the radiographic appearance and histopathological findings were compared. Computed tomography images revealed that the lesion had a multilocular structure with many smaller septa at its periphery. Although expansion toward the maxillary sinus was suggested radiologically, invasion of the mucosa into the floor of the maxillary sinus was found on histopathological examination.

Extremely aggressive behavior of central giant cell granuloma after biopsy:a case report

Although central giant cell granulomas (CGCGs) appear to be benign, their radiographic findings are active. These tumors become severely invasive with the stimulus of surgery, resembling malignant tumors. Achieving the correct diagnosis is reportedly difficult because CGCGs are very similar to odontogenic jaw tumors. We herein describe an intriguing case of a 21-year-old male patient who was referred to our outpatient clinic with persistent swelling of the left buccal region. After making a provisional diagnosis of ameloblastoma from panoramic and computed tomography images, a biopsy was performed. Nine days after this operation, the intraoral lesion started to enlarge, causing facial disfigurement. Soon afterward, this lesion was examined by computed tomography, magnetic resonance imaging, and by both bone and tumor scintigraphy. Segmental resection of the mandible was conducted in the hospital, and the histopathological appearance was consistent with CGCG. Although CGCG tends to be indolent, the present case suggests that the stimulus of surgery can trigger clinically invasive behavior more characteristic of malignancy. CGCG exhibits variable features, but with the stimulus of surgery, its clinical behavior becomes extremely invasive, resembling a malignant tumor. The CGCG in the present case showed unusual development and intriguing radiographic and histopathological findings. It is important to be aware of the findings that can help to achieve a correct diagnosis.