Objective To investigate the effect of EZH2 on apoptosis and radiosensitivity of squamous cell carcinoma of tongue.Methods Tongue squamous carcinoma cells Tca-8113 were transfected with small interfering RNA of EZH2 (EZH2 siRNA1,EZH2 siRNA2) and its negative controls (siRNA-NC),the expression levels of EZH2 were detected by RT-PCR and Western blot and EZH2 siRNA2 was used for further studied since its better interference efficiency.The cells with siRNA transfection were irradiated with 8 Gy doses,and cell proliferation was detected by MTT,apoptosis was detected by flow cytometry,the expression of p-STAT3,STAT3 and Cleaved Caspase-3 was detected by Western blot.In addition,the cells were irradiated with 0,2,4,6,and 8 Gy to detect radiosensitivity by cell colony formation assay.Results EZH2 siRNA1 and EZH2 siRNA2 decreased the expression of EZH2 in Tca-8113 cells and EZH2 siRNA2 had a better interference efficiency (tmRNA =8.660,PmRNA ＜ 0.01;tprotein =2.883,Pprotein ＜0.05).The apoptotic rate in the EZH2 siRNA group was (29.90 ± 1.64)％,and was increased by 8 Gy irradiation to (38.17 ± 1.59) ％ (t =4.742,P ＜ 0.05).At the same time,EZH2 siRNA reduced the level of p-STAT3,but promoted the expression of Cleaved Caspase-3 protein,and enhanced the sensitivity of Tca-8113 cells to 1.668-times of control.Conclusions Interfering EZH2 could promote apoptosis,inhibit proliferation and increase radiosensitivity of squamous cell carcinoma of tongue.

Objective To evaluate the clinical outcomes of internal fixation with extra-articular distal humerus locking compression plate (LCP) for the treatment of mid-distal humerus diaphyseal fracture.Methods From December 2012 to December 2016,a cohort of 22 patients with mid-distal humerus shaft fracture were treated by open reduction and internal fixation using extra-articular distal humerus LCP.They were 14 males and 8 females with an average age of 42.7 years (range,from 18 to 86 years).According to AO classification,there were 13 cases of type 12-A,7 cases of type 12-B,and 2 cases of type 12-C.The surgical time,intra-operative blood loss and hospital stay were recorded.The clinical outcomes were evaluated by the Mayo elbow performance score (MEPS) at the last follow-ups.Results Surgical time ranged from 46 to 95 minutes with an average of 57 minutes.The average blood loss was 220 mL (range,from 150 to 400 mL).The average hospital stay was 10.5 days (range,from 9 to 13 days).The mean follow-up was 23.8 months (range,from 6 to 48 months).Bone union was achieved in 21 cases after an average of 4.6 months (range,from 3 to 9 months),and one patient experienced bone non-union which was uneventfully healed after secondary auto platelet rich plasma (PRP) graft management.The average MEPS elbow performance score was 88.2,resulting in 16 excellent,4 fine and 2 fair cases (excellent and fine rate:90.9％).Conclusions Since extra-articular distal humerus LCP can provide stable internal fixation,facilitating early postoperative rehabilitation,it may be considered an effective alternative osteosynthesis for mid-distal comminuted humeral diaphyseal fractures.

Objective: To investigate the effect of the multi-material artifact reduction (MMAR) algorithm of spectral CT in reducing the beam hardening artifacts in dental restoration material. Methods: Three-unit fixed bridge restorations were fabricated on the first to third molars in pig jaw. Gold alloy, zirconia, cobalt chromium alloy, nickel chromium alloy and pure titanium were used as materials for these fixed bridges. After restoration delivery, the pig jaw was scaned using energy spectrum CT machines. Images in regular 120 kVp scan mode were used as conventional group, and reconstructed single-energy horizontal images of 80, 90, 100, 110, 120, 130 and 140 keV in energy spectrum scanning mode were used as energy spectrum group, and reconstructed images applied MMAR technology in energy spectrum scanning mode were used as energy spectrum MMAR group. Each group was scanned 10 times to measure CT value and noise of muscles around dental prosthetic materials and adjacent non-artifact layers. Artifact index was calculated. Two radiologists scored the image quality of each group subjectively. Kruskal Wallis rank sum test was used to compare the difference of image noise, artifact index and subjective score among the control group and the best keV condition in the energy spectrum group and the energy spectrum MMAR group. Results: The image noise of energy spectrum group and energy spectrum MMAR group decreased gradually with the increase of single energy level. The artifact index of pure titanium restorations in conventional group, energy spectrum group and energy spectrum MMAR group were 71.0±8.0, 21.4±2.7 and 14.7±2.7 respectively, and these values were significantly lower than those of other materials in the same group (P<0.05). The subjective image quality scores in energy spectrum MMAR group were as follows: 3.0±0.2 for gold alloy, 4.3±0.5 for zirconia, 3.0±0.4 for cobalt chromium alloy, 3.1±0.4 for cobalt chromium alloy, and 4.6±0.5 for pure titanium. These scores were significantly smaller than those in the conventional group (P<0.05). There was no significant difference in noise between energy spectrum group and energy spectrum MMAR group (P>0.05), and the noise values in energy spectrum group and energy spectrum MMAR group were significantly lower than that in the conventional group (P<0.05). Conclusions Artifacts of pure titanium is minimal. Energy spectrum CT combined with MMAR technology can effectively reduce the artifacts of gold, zirconia, cobalt-chromium alloy, nickel-titanium alloy and pure titanium. This technique can be used as an effective method to remove artifacts of dental prosthesis.