Objective:To analyse the difference of torque performance between lingual and labial brackets as well as the influence of the archwires of different materials with different dimension on the torque capability of lingual brackets.Methods:The 3D finite mo-del of lingual and labial brackets from the right upper canine to the left upper canine was established,all brackets were with 0.56 mm slot size.The center of the bracket slot of the left upper central incisor was used as the central point and the two brackets were rotated clockwise and counterclockwise with a rotation angle of ±20°along the horizontal axis of bracket slot.The torque load on the left up-per central incisors with different materials and dimensions of the archwires was simulated.Results:The torque force of both lingual and labial brackets increased with the increase of rotation angle and the elastic modulus of archwire.The lingual archwire generated torque force was nearly 3 -5 times more than the labial system under the same torque angle.The torque value generated with 0.48 mm ×0.64 mm archwires was greater than 0.43 mm ×0.64 mm.The lingual bracket generated torque force decreased gradually from nickel-titanium(NiTi),Beta-titanium(TMA)to stainless steel(SS)under the same dimension.Conclusion:Torque moments of lin-gual and labial brackets both increases with the increase of torque angle in each operating condition.The lingual orthodontic brackets produce more torque force than labial brackets under the same torque angle.Torque performance of lingual bracket was affected by the material and dimension of the archwires.

TBL (Team-based learning) model is a new teaching method.By evaluating the effect of TBL model in theory teaching on Chinese orthodontic postgraduate program in the department of Orthodontics,Guanghua School of Stomatology,Sun Yat-sen University,and comparing the traditional teaching model which centered on teachers,we have probed into the application experience of TBL teaching method in curriculum setting of preclinical theoretic learning in orthodontics postgraduate education.The result shows TBL has significantly enhanced students' enthusiasm for learning,sense of collaboration,and has improved the quality of education.TBL method is better,even though there is something that needs to be improved.

ObjectiveTo investigate the expressions of nerve growth factor (NGF) and its receptors TrkA and p75NTR in dermatofibrosarcoma protuberans and dermatofibroma.MethodsAvidin-biotin immunohistochemical(ABC) method was used to detect the expressions of NGF and its receptors TrkA and p75NTR in paraffin-embedded tissue specimens from 17 cases of DFSP and 15 cases of dermatofibroma.Results NGF and TrkA were highly expressed in both DFSP and dermatofibroma specimens,with no significant difference between the two groups of specimens (x2 =0.11,0.02,respectively,both P ＞ 0.05),while the expression of p75NTR was significantly higher in DFSP than in dermatofibroma specimens(x2 =32,P ＜ 0.01 ).The expression of NGF was positively correlated with that of p75NTR in DFSP(R2 =0.623,P ＜ 0.01 ).ConclusionNGF may play a certain role in the development of DFSP via its high-affinity receptor TrkA and low-affinity receptor p75NTR.

Objective To detect the expressions of nerve growth factor (NGF) and its receptors tyrosine kinase A (TrkA) as well as p75 neurotrophin receptor (p75NTR) in the lesions of lichen planus.Methods Biopsy specimens were collected from the lesions of 32 patients with lichen planus and normal skin of 12 healthy human controls and subjected to paraffin embedding.Immunohistochemical avidin-biotin complex (ABC) method was used to detect the expressions of NGF,TrkA and p75NTR.Results NGF and TrkA,which were located in the cytoplasm of keratinocytes,were strongly or moderately expressed in the lesional skin specimens,but absent or weakly expressed in the normal skin specimens (both P ＜ 0.01).No significant differences were observed in the expression of p75NTR between the lesional and normal skin specimens,or in the expressions of NGF,TrkA or p75NTR among specimens from patients in different age groups,patients of different gender or lesions at different sites (all P ＞ 0.05).There was a positive correlation between the expression of NGF and TrkA in the lesions of lichen planus (R2 =0.535,P ＜ 0.01).Conclusion NGF may play a certain role in the development of lichen planus via its highaffinity receptor TrkA.

Objective To study the effect of siRNA targeting survivin gene on the apoptosis of malignant melanoma cell line A375. Methods The eucaryotic expression vector of pU-survivin-siRNA was constructed and transfected into the A375 cells by electroporation. The protein expression of survivin was examined by Western blotting, and cell apoptosis by flow cytometry. Results The transfection of pU-sur-vivin-siRNA significantly down-regulated survivin expression ( 0.24 ?0.02 in the transfected group versus 0.98 ?0.21 in the control group ) in A375 cells, and promoted cell apoptosis ( 83% in the transfected group versus 28% in the control group, P

OBJECTIVE:To evaluate the therapeutic effect of compound glycyrrhizin plus mizolastine for patients with generalized neurodermatitis(GND)and its influence on patietents' psychology.METHODS:60 patients with GND were randomly assigned to receive compound glycyrrhizin plus mizolastine(treatment group)or mizolasitine alone(control group)for 28 days.The psychological factors were examined before and after treatment using self-rating anxiety scale(SAS),and the curative effects and the psychological changes between two groups were compared.RESULTS:The SAS scores of treatment group and control group were 30.53? 1.50 and 33.20? 1.67,respectively(P

Objective To investigate the potential role of Spa-1 in the development and metastasis of EMPD.Methods Tissue specimens were resected from 17 patients with primary EMPD,12 patients with invasive EMPD and 9 normal human controls.Immunohistochemistry was performed to measure the expression of spa-1 and Ki-67.Results Positive staining was observed for Spa-1 in cytoplasm,and for Ki-67 in cell nuclei.Spa-1 and Ki-67 were weakly expressed in the basal layer of normal skin.The expression of Spa-1 and Ki-67 in EMPD tissue were statistically higher than those in the normal control tissue (both P<0.01).Increased expression of Spa-1 was noted in invasive EMPD tissue compared with in situ EMPD tissue.The expression of Spa-1 was positively correlated with that of Ki-67 in the tissue of EMPD.Conclusion Spa-1 may play a certain role in the initiation and progression of EMPD.

A 46-year-old male patient developed scatterred reddish-brown plaques and nodules on the back 6 years prior to the presentation. Then, the lesions gradually spread to the axillary fossa and protothorax, and became indurated with slight itching in winter. Laboratory examination revealed hypergammaglobulinemia. Computed tomography(CT)scan showed multiple nodular or patchy shadows in both lungs, lymphadenectasis in axillary, mediastinal and inguinal regions, and spleen enlargement. Histopathological examination of skin lesions showed granulomatous infiltrates with plenty of lymphocytes, histiocytes and mature plasma cells in the middle and lower dermis with the presence of lymphoid follicle-like structures, but no cell atypia was observed. Immunohistochemical study showed positive staining for CD38, CD138, CD79a, κ and λ light chains. According to clinical manifestations and laboratory examination results, the patient was diagnosed with cutaneous and systemic plasmacytosis.

BACKGROUND:In the orthodontic treatment, double wire technique is commonly used to correct the torque of anterior teeth;however, the underlying mechanical mechanisms remain unclear. OBJECTIVE:To study the torque capabilities of DamonQ system through the three-dimensional finite element method. METHODS:Three-dimensional finite element models of Damon Q brackets with different dimension arch wires were established and were grouped according to arch wire with different dimensions. The torque capabilities of Damon Q system with different dimensions and materials arch wire were analyzed. RESULTS AND CONCLUSION:The Damon Q brackets with single or double wires had the same variation of torque, torque angle curve changes under the condition of different size and material arch wires. Torque moment increased gradually with increasing torque angle. Rectangular-round double wires produced larger torque moment compared with single rectangular wire, whereas double round wires produced smal er torque moment compared with single rectangular wire. The torque moment produced by rectangular-round double wires or by single rectangular wire was approximately 2-8 times or 1-5 times more than that by double round wires. The torque moment that rectangular-round double wires produced was larger than that single wire produced in the DamonQ system. In the early clinical practice, we can use double round wires to control root movement. In the middle-term of the treatment, we can use rectangular-round double wires to control root movement as the mild forces produced by them reduce root absorption. This study lays a foundation for the application of Damon Q bracket with double wire technology in the clinic.

Objective To investigate the inhibitory effects of L. monocytogenes expressing melanomainhibiting activity(MIA)gene on malignant melanoma.Methods The plasmid pERL3-hly-MIA was constructed and used to transform live L.monocytogenes by electroporation.Atier culture.the transformed L.monocytogenes,namely LM-hly-MIA,was harvested for the detection of MIA protein by Westem Blot.A total of 24 mice were divided into three groups,namely control group,LM group and LM-hly-MIA group,to be immunized with physiological saline,L.monocytogenes and LM-hly-MIA,respectively.One day after the immunization.mice were subcutaneously inoculated with 0.1 mL of B16 cells at a concentration of 1×107/mL.One week later.reimmunization was performed.The size and weight of tumors were observed and measured in these mice.Results Enzyme digestion and Western blot confirmed the Successful construction of plasmid pERL3-hly-MIA.The average weight of tumors in mice was 4.33±0.91 gram.3.36 ±0.41 gram and 1.89±0.52 gram,respectively in the control group,LM group and LM-hly-MIA group,respectively(P＜0.05).with the inhibition rates of tumor growth being 22.4%and 61.5%in LM group and LM-hly-MIA group.respectively.Conclusion The attenuated strain of L.monocytogenes expressing MIA gene could evidently inhibit melanoma growth.