G2A as a key modulator of carbonyl stress and apoptosis resistance in glucose-loaded cancer cells.

Cancer cells exhibit high glycolytic activity, metabolizing glucose as their primary energy substrate. Toxic metabolites produced during glycolysis, such as methylglyoxal, induce carbonyl stress (CS), promoting inflammation and oxidative stress. The elevated glucose metabolism in cancer cells creates this toxic environment. However, little research has focused on the molecules mediating these reactions and stresses, and their role in selecting and enriching apoptosis-resistant cells. This study investigated the impact of constitutively suppressing oxidized lipid receptor G2A (GPR132) expression on the relationship between CS and oxidative stress in glucose-loaded cancer cells. G2A has recently attracted attention as a tumor promoter. However, our study shows that G2A suppression under glucose loading significantly reduces CS and associated oxidative stress, thereby enhancing cancer cell survival. This suggests a new mechanism contrary to conventional thinking, involving the acute induction of glyoxalase 1 (Glo1). G2A may thus play a role in selecting and enriching apoptosis-resistant cell populations under high glucose conditions by regulating Glo1 expression. These findings improve our understanding of the adaptive capacity of cancer cells to glucose toxicity.

Piezosurgery for Intraosseous Venous Malformation of the Mandible.

Intraosseous venous malformation of the mandible is rare. A 59-year-old woman was referred to our hospital for evaluation of a radiolucent lesion in the left body of the mandible that had been detected on a routine radiologic dental checkup. The patient wished for follow-up rather than operation. After 2 years' follow-up, the radiolucent lesion had slowly grown, and the patient decided to have an operation. The lesion was removed surgically using the piezosurgery system, and conservation of the inferior alveolar nerve was achieved under general anesthesia. After operation, she reported an initial change in sensation (paresthesia). The sensitivity was recovered after 6 months. Patient prognosis has been good to date, with no symptoms indicating recurrence. We used to treat intraosseous venous malformations using the piezosurgery system. The present report describes a patient with intraosseous venous malformation of the mandible by complete excision and conservation of the nerve. It was useful to use piezosurgery for conservation of inferior alveolar nerve.

C-arm-guided reduction of zygomatic fractures revisited.

BACKGROUND: Anatomic reduction of the zygomatic arch, a key surgical landmark for midfacial width and projection, is essential for the treatment of combined fractures of the zygomaticomaxillary complex and zygomatic arch. Reduction control in surgery for this common facial fracture would be facilitated by intraoperative real-time assessment using widely available and reliable equipment. Although C-arm fluoroscopy is routinely used in the repair of orthopedic fractures, its use in the maxillofacial region, particularly for combined zygomatic fractures, has been scarcely reported. METHODS: We prospectively evaluated C-arm-guided reduction in 38 patients of combined zygomatic fracture without concurrent craniofacial fractures. Patients were classified according to the presence or absence of bone contact in the displaced zygomatic arch, namely as conserved (C) and loss (L) types, respectively. Reduction status was determined by the degree of recovery of the malar prominence and arch shape. RESULTS: In all cases, C-arm imaging clearly displayed the displaced zygomatic arch and body in a single image. Cumulative fluoroscopic time was a few minutes in all cases. Total reduction status was excellent in 21 patients and good in 17. No case was classified as fair or poor. Repair was significantly more favorable in type C than in type L cases (p = 0.0016). CONCLUSIONS: In combined zygomatic fractures, the C-arm technique provides easy, flexible, and time-efficient adjustment. Its comprehensive imaging for zygomatic arch shape and body contour markedly facilitates the control of fracture reduction and protects against unexpected, unsatisfactory outcomes.

Involvement of RhoA and RalB in geranylgeranyltransferase I inhibitor-mediated inhibition of proliferation and migration of human oral squamous cell carcinoma cells.

PURPOSE: Geranylgeranyltransferase I is required for the prenylation of the small GTPases. The effect of GGTase I inhibitors (GGTIs) on oral squamous cell carcinoma (SCC) cells was examined. METHODS: The GGTI-treated cells were examined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) assay, flow cytometric analysis, transwell chamber assays, and immunofluorescent staining. Small GTPases were detected by immunoblot analysis, and siRNA were used for silencing RalA and RalB. RESULTS: GGTI suppressed the proliferation of oral SCC cells and induced cell cycle arrest at G(1), but the sub-G(1) fraction was small. The expression of the cyclin-dependent kinase (CDK) inhibitor p21(Waf1/Cip1), but not p27(Kip1), was markedly increased by GGTI. There was an apparent increase in the expression and reduction in the membrane localization of RhoA and RalB, but not Ras and RalA. Assays with transwell chambers and wound healing and invasion revealed the migrative and invasive capabilities of SAS cells to be inhibited by GGTI. Actin filaments were rearranged and stress fibers and peripheral cell processes were lost, accompanying cell rounding. siRNA for RalB, but not RalA, significantly suppressed the migration of SAS cells. CONCLUSION: These results suggest that GGTI inhibits the geranylgeranylation of RhoA and increases the p21(Waf1/Cip1) level, resulting in cell cycle arrest at G(1) to decrease cell proliferation, and that of RalB to suppress the migration and invasion by oral SCC cells. GGTIs may be useful as inhibitors of invasion and metastasis in cases of oral SCC.

Development of a simulation system in mandibular orthognathic surgery based on integrated three-dimensional data.

PURPOSE: Surgical simulation should reflect the 3D movement of dentition and the resultant movement of the osteotomized segments, which can influence surgical outcome. The present study was aimed at developing a new simulation system that enables virtual osteotomy of a given surgical situation and evaluation of the bony interference between the osteotomized segments of the mandible. SUBJECTS AND METHODS: The data of 3D computer tomography (CT) for maxillomandibular dental casts were integrated into the standard coordinates of a 3D cephalogram. To evaluate the accuracy of the system, measurement errors of the 3D CT virtual model from a dry skull were compared with the computer simulation system and a contact-type 3D digitizer. To examine the clinical accessibility, 15 mandibular prognathism patients with mild to severe asymmetry were evaluated with the simulation program. RESULTS: The average error of measurement in all directions was 1.31 mm. It was possible to simulate various osteotomy procedures by conversion of the 3D coordinates of the dental cast and CT data into the standard coordinate system of a 3D cephalogram. Using this simulation system, it was possible to prevent condylar torque or segment malpositioning by removing the bony interference visualized by a 3D virtual model. CONCLUSION: A new system, which enables the precise visualization of osteotomized segments and calculation of bony interference, was proposed in the present study. This new system provides an acceptable precision of treatment planning of orthognathic surgery, especially for facial asymmetry.

Bilateral multiple spindle cell lipomas of the tongue.

Spindle cell lipoma (SCL) typically occurs in elderly men as a solitary lesion in the posterior neck and back, but less commonly also involves the oral cavity. Here, we describe a rare case of bilateral multiple SCLs of the tongue. The patient was a 72-year-old Japanese man with multiple painless soft nodules in the bilateral margins of the tongue. The patient was not obese, and had used alcohol moderately for more than 40 years. A clinical diagnosis of multiple tongue lipomas was made. The tumors were resected surgically, and they exhibited the histopathological features of SCL, composed of mature fat cells, collagen-forming CD34-positive spindle cells, and sparse mast cells. This suggests that differential diagnosis of intraoral multiple lipomatous nodules should include not only lipomatosis but also multiple SCLs, notwithstanding the rare incidence of the latter.

Maxillary distraction osteogenesis in cleft lip and palate patients with skeletal anchorage.

OBJECTIVE: Maxillary distraction osteogenesis with the rigid external distraction (RED) system has been used to treat cleft lip and palate (CLP) patients with severe maxillary hypoplasia. We introduce maxillary distraction osteogenesis for CLP patients with skeletal anchorage adapted on a stereolithographic model. PATIENTS: Six maxillary deficiency CLP patients treated according to our CLP treatment protocol had undergone maxillary distraction osteogenesis. METHOD: In all patients, computed tomography (CT) images were recorded preoperatively, and the data were transferred to a workstation. Three-dimensional skeletal structures were reconstructed with CT data sets, and a stereolithographic model was produced. On the stereolithographic model, miniplates were adapted to the surface of maxilla beside aperture piriforms. The operation performed involved a high Le Fort I osteotomy with pterygomaxillary disjunction. Miniplates were fixed to the maxillary segment with three or four screws and used for anchorage of the RED system. Retraction of the maxillary segment was initiated after 1 week. RESULTS: The accuracy of the stereolithographic models was enough to adapt the miniplates so that there was no need to readjust the plates during surgery. Postoperative cephalometric analysis showed that the direction of the retraction was almost parallel to the palatal plane, and dental compensation did not occur. CONCLUSIONS: We performed maxillary distraction osteogenesis with skeletal anchorage adapted on the stereolithographic models. Excellent esthetic outcome and skeletal advancement were achieved without dentoalveolar compensations.

Control of diastereoselectivity in the crotylation and cinnamylation of aldehydes by the selection of ligands on allylic indium reagents.

Diastereoselective couplings of salicylaldehyde, anisaldehyde and 2-pyridylaldehyde with crotyl- and cinnamylindium reagents were studied. The syl/anti selectivity was found to depend largely on the ligands on the indium atom of the allylic indium reagents. A syn-selective cinnamylation of salicylaldehyde was realized by the combination of cinnamyl acetate and indium(I) iodide, whereas an anti-selective coupling with salicylaldehyde was achieved by the indium trichloride/aluminium-mediated cinnamylation.