Effects of 2-deoxy-D-glucose and quercetin on osteoblastic differentiation and mineralization in irradiated MC3T3-E1 cells / 대한구강악안면방사선학회지

PURPOSE: To investigate the in vitro response of MC3T3-E1 osteoblastic cells to X-ray in the presence and absence of 2 deoxy-D-glucose (2-DG) and quercetin (QCT). MATERIALS AND METHODS: The MC3T3-E1 cells were cultured in an alpha-MEM supplemented with 5 mM 2-DG or 10 micrometer QCT and then the cells were incubated for 12 h prior to irradiation with 2, 4, 6, and 8 Gy using a linear accelerator (Mevaprimus, Germany) delivered at a rate of 1.5 Gy/min. At various times after the irradiation, the cells were processed for the analyses of proliferation, viability, cytotoxicity, and mineralization. RESULTS: Exposure of the cells to X-ray inhibited the tritium incorporation, 3-(4, 5-dimethylthiazol-2yl-)-2, 5- diphenyl tetrazolium bromide (MTT)-reducing activity, and alkaline phosphatase (ALP) activity, and caused cytotoxicity and apoptosis in a dose-dependent manner of the X-ray. This effect was further apparent on day 3 and 7 after the irradiation. RA+2-DG showed the decrease of DNA content, cell viability, and increase of cytotoxicity rather than RA. ALP activity increased on day 7 and subsequently its activity dropped to a lower level. 2-DG suppressed the calcium concentration, but visual difference of number of calcified nodules between RA and RA+2-DG was not noticed. RA+QCT showed the increase of DNA content, cell viability, but decrease of cytotoxicity and subG1 stage cells in the cell cycle, and increased calcified nodules in von Kossa staining rather than the RA. ALP activity showed significant increases on day 7 and subsequently its activity dropped to a lower level. CONCLUSION: The results showed that the 2-DG acted as a radiosensitizing agent and QCT acted as a radioprotective agent respectively in the irradiated MC3T3-E1 osteoblast-like cells.

Effects of 2-deoxy-D-glucose and quercetin on cytokine secretion and gene expression of type I collagen during osteoblastic differentiation in irradiated MC3T3-E1 cells / 대한구강악안면방사선학회지

PURPOSE: To characterize the effects of 2-deoxy-D-glucose (2DG) and quercetin (QCT) on cytokine secretion of IL-6, TGF-beta and gene expression of Col I in irradiated MC3T3-E1 cells. MATERIALS AND METHODS: The MC3T3-E1 cells were cultured in an alpha-MEM supplemented with 5 mM 2DG or 10 mM QCT and then the cells were incubated 12h before irradiation with 2, 4, 6, and 8 Gy X-ray using a linear accelerator delivered at a dose rate of 1.5 Gy/min. Level of IL-6 and TGF-beta was determined by ELISA. Also expression of Col I was examined by RT-PCR. RESULTS: In accordance with the radiation dose, the amount of TGF-beta was not different in RA+QCT, but it showed a peak value in control and RA+2DG at 4Gy on the 3rd day. However, all groups showed a decreasing tendency dose-dependently in RA+QCT on the 7th day (p< 0.01). In accordance with the radiation dose, the amount of IL-6 increased dose-dependently in all groups on the 3rd day. On the 7th and 21st day, all groups showed peak values at 4Gy. RA+QCT showed a slightly increased amount of IL-6 at 2 Gy, but it showed a slightly decreased amount at 4, 6, and 8 Gy. In accordance with the period of culture after irradiation, the expression of Col I increased dosedependently in RA+QCT. CONCLUSIONS: The result showed that QCT acted as radiosensitizer in the secretion of TGF-beta and gene expression of Col I during differentiation in irradiated MC3T3-E1 cells at the cellular level.

Metastatic gastric adenocarcinoma to the mandible / 대한구강악안면방사선학회지

Metastatic tumors to the jaw bones are uncommon. The most common metastatic tumors to the jaw bones are the breast, lung and kidney. In the jaw bones, the common location of the lesions is the mandible, and the posterior area of the mandible is more commonly affected. The radiographic appearance is quite variable. In this report, a very rare case of metastatic gastric adenocarcinoma to the mandible is presented. The patient had undergone a gastrectomy 3 years ago.

Osteoradionecrosis of the jaws / 대한구강악안면방사선학회지

Osteoradionecrosis is one of the most serious complication after heavy irradiation of bone and most particularly following treatment of cancers within the head and neck. The irradiated bone has the decreased vascularity and is easily infected. As a result, the spread of infection may cause a nonhealing wound that is very difficult to be treated. A comprehensive prophylactic dental care as well as proper blocking of the radiation field before radiotherapy must be considered to reduce the risk of osteoradionecrosis. We present three cases of osteoradionecrosis which developed after extraction of teeth in irradiated patients.

Positional and morphologic changes of the temporomandibular joint disc using magnetic resonance imaging / 대한구강악안면방사선학회지

PURPOSE: To evaluate displacement and morphologic changes of the temporomandibular joint (TMJ) disc in patient with internal derangement using magnetic resonance imaging (MRI). MATERIALS AND METHODS: One hundred and forty five MR images of TMJs in 73 patients were evaluated. Positional and morphologic changes of the TMJ discs were assessed. Lateral or medial disc displacement was also evaluated on coronal images. RESULTS: Among 63 discs with anterior disc displacement, 37 discs were assessed as a biconcave disc and 21 as a deformed disc. Rotational disc displacement was observed in 35 discs. Anteromedial disc displacement was observed in 29 discs, and anterolateral direction in 6 discs. Among 35 rotational displacement, 5 biconcave discs and 21 deformed discs were observed. CONCLUSION: Rotational and sideways displacement of TMJ discs were found to be common and an important aspect of internal derangement. This study also suggests that sagittal and coronal images of the TMJ have complementary abilities for an assessment of joint abnormality.

Inflammatory pseudotumor of the midfacial area / 대한구강악안면방사선학회지

Inflammatory pseudotumor was originally described in the lung, but recently has been recognized to occur in various sites. A 56-year-old female was referred to our department with a painless swelling of the right midfacial area since 3 months ago. Clinical examination showed non-specific intraoral findings, but asymmetric facial appearance and numbness of the right midfacial area. Plain radiographs and CT images showed aggressive destruction and irregular thickening of the right maxillary sinus wall, increased antral opacification, and destruction of the zygomatic arch. A relatively well-defined soft tissue mass occupied the right maxillary sinus, nasal cavity, zygoma, and infraorbital region. The soft tissue mass showed mild enhancement on CT. Radiographically, this lesion presented a rapidly enlarging mass demonstrating aggressive behavior, mimicking a malignant tumor. Histopathologic examinations showed plasma cells and inflammatory cells in variable fibrotic tissues and demonstrated positive reactivity for vimentin. No malignent changes could be found.

Inflammatory pseudotumor of the midfacial area / 대한구강악안면방사선학회지

Inflammatory pseudotumor was originally described in the lung, but recently has been recognized to occur in various sites. A 56-year-old female was referred to our department with a painless swelling of the right midfacial area since 3 months ago. Clinical examination showed non-specific intraoral findings, but asymmetric facial appearance and numbness of the right midfacial area. Plain radiographs and CT images showed aggressive destruction and irregular thickening of the right maxillary sinus wall, increased antral opacification, and destruction of the zygomatic arch. A relatively well-defined soft tissue mass occupied the right maxillary sinus, nasal cavity, zygoma, and infraorbital region. The soft tissue mass showed mild enhancement on CT. Radiographically, this lesion presented a rapidly enlarging mass demonstrating aggressive behavior, mimicking a malignant tumor. Histopathologic examinations showed plasma cells and inflammatory cells in variable fibrotic tissues and demonstrated positive reactivity for vimentin. No malignent changes could be found.