Well-Differentiated Extraskeletal Osteosarcoma Arising from the Retroperitoneum That Recurred as Anaplastic Spindle Cell Sarcoma

Extraskeletal osteosarcoma is an uncommon high-grade malignant soft tissue sarcoma. Well-differentiated extraskeletal osteosarcoma is thought to have a better prognosis than classical extraskeletal osteosarcoma, but dedifferentiation after recurrence has also been reported. We present a case of a primary retroperitoneal extraskeletal osteosarcoma in a 62-year-old Japanese woman. Abdominal CT revealed a large mass with diffuse calcification in the right retroperitoneal space and tumor resection was performed. The histopathological diagnosis was well-differentiated retroperitoneal extraskeletal osteosarcoma. She was followed up by CT every 6 months without adjuvant radiotherapy and chemotherapy for 31 months until anaplastic high-grade spindle cell sarcoma recurred in the retroperitoneum. Our case is the seventh reported description of well-differentiated extraskeletal sarcoma, and the first to arise in the retroperitoneum and recur as an entirely dedifferentiated spindle cell sarcoma

Alveolar Bone Microstructure Surrounding Orthodontic Anchor Screws with Plasma Surface Treatment in Rats

A lateral load was applied to anchor screws that had undergone surface treatment, and the structure, cellular dynamics, and quality of the bone surrounding anchor screws were analyzed to investigate the effect of this surface treatment on the peri-implant jawbone. In addition, bone microstructural characteristics were quantitatively evaluated for each site of loading on the bone around the anchor screw. Rats were euthanized after observation on days 3, 5, or 7, and bone quality analyses were performed. Bone–implant contact rate increased more rapidly at an early stage in the treated surface group than in the untreated surface group. Bone lacuna morphometry showed that the measured values adjacent to the screw at the screw neck on the compressed side (A) and at the screw tip on the uncompressed side (D) were significantly lower than those at the screw tip on the compressed side (B) and at the screw neck on the uncompressed side (C). Collagen fiber bundle diameter showed that the measured values adjacent to regions A and D were significantly higher than those at regions B and C. Anchor screw surface activation facilitates initial bone contact of the screw, suggesting that early loading may be possible in clinical practice.Okawa K., Matsunaga S., Kasahara N., et al. Alveolar Bone Microstructure Surrounding Orthodontic Anchor Screws with Plasma Surface Treatment in Rats. Journal of Functional Biomaterials 14, 356 (2023); https://doi.org/10.3390/jfb14070356

A radiobrominated tyrosine kinase inhibitor for egfr with l858r/t790m mutations in lung carcinoma

金沢大学疾患モデル総合研究センターActivating double mutations L858R/T790M in the epidermal growth factor receptor (EGFR) region are often observed as the cause of resistance to tyrosine kinase inhibitors (TKIs). Third‐generation EGFR‐TKIs, such as osimertinib and rociletinib (CO‐1686), was developed to target such resistance mutations. The detection of activating L858R/T790M mutations is necessary to select sensitive patients for therapy. Hence, we aimed to develop novel radiobromine‐labeled CO‐ 1686 as a positron emission tomography (PET) imaging probe for detecting EGFR L858R/T790M mutations. Nonradioactive brominated‐CO1686 (BrCO1686) was synthesized by the condensation of N‐(3‐[{2‐chloro‐5‐(trifluoromethyl)pyrimidin‐4‐yl}amino]‐5‐bromophenyl) acrylamide with the corresponding substituted 1‐(4‐[4‐amino‐3‐methoxyphenyl]piperazine‐1‐yl)ethan‐1‐one. The radi-obrominated [77 Br]BrCO1686 was prepared through bromodestannylation of the corresponding tributylstannylated precursor with [77Br]bromide and N‐chlorosuccinimide. Although we aimed to provide a novel PET imaging probe,77Br was used as an alternative radionuclide for76Br. We fun-damentally evaluated the potency of [77Br]BrCO1686 as a molecular probe for detecting EGFR L858R/T790M using human non‐small‐cell lung cancer (NSCLC) cell lines: H1975 (EGFR L858R/T790M), H3255 (EGFR L858R), and H441 (wild‐type EGFR). The BrCO1686 showed high cy-totoxicity toward H1975 (IC50 0.18 ± 0.06 μM) comparable to that of CO‐1686 (IC50 0.14 ± 0.05 μM). In cell uptake experiments, the level of accumulation of [77Br]BrCO1686 in H1975 was significantly higher than those in H3255 and H441 upon 4 h of incubation. The radioactivity of [77Br]BrCO1686 (136.3% dose/mg protein) was significantly reduced to 56.9% dose/mg protein by the pretreatment with an excess CO‐1686. These results indicate that the binding site of the radiotracers should be identical to that of CO‐1686. The in vivo accumulation of radioactivity of [77Br]BrCO1686 in H1975 tumor (4.51 ± 0.17) was higher than that in H441 tumor (3.71 ± 0.13) 1 h postinjection. Our results suggested that [77Br]BrCO1686 has specificity toward NSCLC cells with double mutations EGFR L858R/T790M compared to those in EGFR L858R and wild‐type EGFR. However, the in vivo accumulation of radioactivity in the targeted tumor needs to be optimized by structural modification. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.CC-BY 4.

Digital Photoelastic Analysis of TAD-Supported Maxillary Arch Distalization

The objective of this study was to determine whether the distribution of compressional and tensional stress around tooth roots is influenced by the position of a temporary anchorage device and the length of the retraction hook during the distalization of the maxillary dentition. A photoelastic orthodontic model was made of photoelastic epoxy resin. Six combinations of three retraction hook lengths and two posterior Temporary skeletal anchorage devices (TAD) positions were established. Stress was applied through an elastic chain for each of the combinations. Digital photoelastic stress analysis measured the compression, tensional stress, and direction around the tooth root. Using this novel photoelastic model, we found that the distribution of compressional and tensional stress during the retraction of the maxillary dentition was significantly influenced by the position of the TAD and the length of the retraction hook

Treatment Option Criteria for Open Bite with Receiver Operating Characteristic Analysis—A Retrospective Study

Temporary anchorage devices (TADs) allow molar intrusion as an additional treatment option to conventional treatment for open bite cases. We investigated the treatment option criteria for open bite treatment. A total of 33 patients with skeletal Class I to Class II open bite who had stable occlusion one year after treatment were enrolled in the study, including 15 patients who had undergone surgical orthodontic treatment, 8 patients who had undergone treatment with molar intrusion, and 10 patients who had undergone treatment with anterior teeth extrusion. Pre-treatment cephalometric analysis of these patients was used for comparison. Furthermore, receiver operating characteristic (ROC) curve analysis was employed to examine the measurement parameters that would be valid as treatment criteria. In the results, FMA showed that patients treated with molar intrusion had a moderately high angle, while those treated with surgical orthodontic treatment had a severe high angle. The area under the curve (AUC) of the ROC curve indicated that FMA is the most appropriate parameter for treatment option criteria. In addition, the cutoff value indicated that the borderline between molar intrusion and surgical orthodontic treatment was 37.5° for FMA. In this study, we suggested criteria for the treatment of open bite with molar intrusion

Quercetin Reduces the Development of 2,3,7,8-Tetrachlorodibenzo-p-dioxin-Induced Cleft Palate in Mice by Suppressing CYP1A1 via the Aryl Hydrocarbon Receptor

Quercetin is a flavonoid with a wide range of pharmacological activities, including anticancer, antioxidant, and anti-inflammatory effects. Since it is a nutrient that can be consumed with a regular diet, quercetin has recently garnered interest. Quercetin acts as a phytochemical ligand for the aryl hydrocarbon receptor (AhR). Cleft lip and palate are among the most frequently diagnosed congenital diseases, and exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) during pregnancy induces cleft palate via AhR. In this study, we investigated the preventive effect of quercetin intake on the TCDD-induced cleft palate and its mechanism of action. The in vivo results suggest that quercetin intake by pregnant mice can prevent cleft palate in fetal mice. In vitro, the addition of TCDD induced a reduction in cell migration and the proliferation of mouse embryonic palatal mesenchymal cells, which was mitigated by the addition of quercetin. The addition of quercetin did not alter the mRNA expression levels of the AhR repressor but significantly suppressed mRNA expression of CYP1A1. In addition, the binding of AhR to a xenobiotic responsive element was inhibited by quercetin, based on a chemically activated luciferase expression assay. In conclusion, our results suggest that quercetin reduces the development of TCDD-induced cleft palate by inhibiting CYP1A1 through AhR