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Licochalcone-A induces intrinsic and extrinsic apoptosis via ERK1/2 and p38 phosphorylation-mediated TRAIL expression in head and neck squamous carcinoma FaDu cells.

We investigated Licochalcone-A (Lico-A)-induced apoptosis and the pathway underlying its activity in a pharyngeal squamous carcinoma FaDu cell line. Lico-A purified from root of Glycyrrhiza inflata had cytotoxic effects, significantly increasing cell death in FaDu cells. Using a cell viability assay, we determined that the IC50 value of Lico-A in FaDu cells was approximately 100 µM. Chromatin condensation was observed in FaDu cells treated with Lico-A for 24 h. Consistent with this finding, the number of apoptotic cells increased in a time-dependent manner when FaDu cells were treated with Lico-A. TRAIL was significantly up-regulated in Lico-A-treated FaDu cells in a dose-dependent manner. Apoptotic factors such as caspases and PARP were subsequently activated in a caspase-dependent manner. In addition, levels of pro-apoptotic factors increased significantly in response to Lico-A treatment, while levels of anti-apoptotic factors decreased. Lico-A-induced TRAIL expression was mediated in part by a MAPK signaling pathway involving ERK1/2 and p38. In xenograft mouse model, Lico-A treatment effectively suppressed the growth of FaDu cell xenografts by activating caspase-3, without affecting the body weight of mice. Taken together, these data suggest that Lico-A has potential chemopreventive effects and should therefore be developed as a chemotherapeutic agent for pharyngeal squamous carcinoma.

Effective dose from direct and indirect digital panoramic units

Purpose This study aimed to provide comparative measurements of the effective dose from direct and indirect digital panoramic units according to phantoms and exposure parameters. Materials and Methods Dose measurements were carried out using a head phantom representing an average man (175 cm tall, 73.5 kg male) and a limbless whole body phantom representing an average woman (155 cm tall, 50 kg female). Lithium fluoride thermoluminescent dosimeter (TLD) chips were used for the dosimeter. Two direct and 2 indirect digital panoramic units were evaluated in this study. Effective doses were derived using 2007 International Commission on Radiological Protection (ICRP) recommendations. Results The effective doses of the 4 digital panoramic units ranged between 8.9 µSv and 37.8 µSv. By using the head phantom, the effective doses from the direct digital panoramic units (37.8 µSv, 27.6 µSv) were higher than those from the indirect units (8.9 µSv, 15.9 µSv). The same panoramic unit showed the difference in effective doses according to the gender of the phantom, numbers and locations of TLDs, and kVp. Conclusion To reasonably assess the radiation risk from various dental radiographic units, the effective doses should be obtained with the same numbers and locations of TLDs, and with standard hospital exposure. After that, it is necessary to survey the effective doses from various dental radiographic units according to the gender with the corresponding phantom.

Biochanin-A antagonizes the interleukin-1β-induced catabolic inflammation through the modulation of NFκB cellular signaling in primary rat chondrocytes.

Biochanin-A, a phytoestrogen derived from herbal plants, protected from the IL-1β-induced loss of proteoglycans through the suppression of matrix degrading enzymes such as matrix metalloproteinase (MMP)-13, MMP-3, MMP-1, and ADAMTS-5 in primary rat chondrocytes and the knee articular cartilage. It also suppressed the expression of IL-1β-induced catabolic factors such as nitric oxide synthase 2, cyclooxygenase-2, prostaglandin E2, and inflammatory cytokines. Furthermore, biochanin-A suppressed the IL-1β-induced phosphorylation of NFκB, and inhibited its nuclear translocation in primary rat chondrocytes. These results indicate that biochanin-A antagonizes the IL-1β-induced catabolic effects through its anti-inflammatory activity that involves the modulation of NFκB signaling.

Biological Effects of the Herbal Plant-Derived Phytoestrogen Bavachin in Primary Rat Chondrocytes

The aim of this study was to examine the anabolic and anticatabolic functions of bavachin in primary rat chondrocytes. With bavachin treatment, chondrocytes survived for 21 d without cell proliferation, and the proteoglycan content and extracellular matrix increased. Short-term monolayer culture of chondrocytes showed that gene induction of both aggrecan and collagen type II, major extracellular matrix components, was significantly upregulated by bavachin. The expression and activities of cartilage-degrading enzymes such as matrix metalloproteinases and a disintegrin and metalloproteinase with thrombospondin motifs were inhibited significantly by bavachin, while tissue inhibitors of metalloprotease were significantly upregulated. Bavachin inhibits the expression of inducible nitric oxide synthase, a representative catabolic factor, and downregulated the expression of nitric oxide, cyclooxygenase-2, and prostaglandin E2 in a dose-dependent manner in chondrocytes. Our results suggest that the bavachin has anabolic and potent anticatabolic biological effects on chondrocytes, which may have considerable promise in treating articular cartilage degeneration in the future.

A repeatedly recurrent desmoplastic ameloblastoma after removal and allobone graft: Radiographic features compared with histological changes.

A 40-year-old man suffered from a repeatedly recurrent desmoplastic ameloblastoma in the right maxillary anterior and premolar regions. During the first visit, the patient was provisionally histopathologically diagnosed with a developmental cyst, and it was confirmed to be unicystic ameloblastoma and resected. Four years later, the lesion recurred, and was diagnosed as a desmoplastic type of ameloblastoma and removed again. Then, 5 years after the second surgery, the lesion recurred again, and was diagnosed as a type containing a follicular pattern, recurrent ameloblastoma. A panoramic radiograph showed a multilocular and mixed radiolucent/radiopaque expansile lesion at the first visit, a unilocular cystic lesion confined to the premolar area at the second visit, and a small soap bubble appearance in the molar area in the final visit. Cone-beam computed tomographic images of the final recurrence of the tumor revealed multiple small cyst-like structures in the right maxillary anterior and posterior regions.

Anatomic evaluation of the retromolar canal by histologic and radiologic analyses

OBJECTIVES The aim of this study was to identify the detailed anatomic morphology of the retromolar canal using histologic sections and cone-beam computed tomography (CBCT) images. MATERIALS AND METHODS Twenty-two sides of the mandible obtained from cadavers and CBCT images of 72 patients (144 sides) were analyzed. All mandibles were prepared using conventional methods of tissue processing, stained with hematoxylin-eosin, and measured to elucidate the composition and dimensions of the retromolar canal with the aid of a light microscope. In addition, the prevalence, course, opening position, and distance of the retromolar canal from the second molar were measured on CBCT images. RESULTS The retromolar neurovascular bundle in the retromolar canal originated from the inferior alveolar neurovascular bundle, and the mean areas of the neurovascular bundle and each artery and nerve contained within it were 0.59, 0.07, and 0.05mm2, respectively. The mean horizontal and vertical diameters of the neurovascular bundle were 0.82 and 0.90mm, respectively. The retromolar canal was detected more often on CBCT images (43.1%, 31 out of 72 patients). It mainly arose vertically (71.0%) from the mandibular canal and opened in the middle portion (57.9%) of the retromolar triangle at a mean distance of 13.13mm from the second molar. CONCLUSIONS The retromolar canal is a normal anatomic structure that is relatively common and contains both a relatively large artery and a nerve. Clinicians need to pay closer attention to vascular problems as well as nerve damage when they are performing surgical procedures in the retromolar area.