OBJECTIVETo evaluate the positions and forms of temporomandibular joints (TMJ) with different vertical skeletal patterns in Class II division 1 patients.

METHODSCone- beam CT scans of 117 Class II division 1 adolescent patients (including 30 patients with high angle, 58 with average angle and 29 with low angle) were selected and reconstructed using Mimics 10.0 software. Fourteen measurements related to the positions and forms of condyle, forms of fossa and joint spaces were performed.

RESULTSCompared with high and average angle patients, the condyles in low angle patients located more posteriorly and inferiorly [the vertical distances between condyle and S was (20.67 ± 1.99)mm and the antero-posterior distances between condyle and S was (9.15 ± 1.61)mm]. The joint fossae were deeper [the fosse depths was (7.83 ± 1.06)mm]. The angles of posterior joint node bevels were bigger [the inclinations were (28.91 ± 3.94)° ]. The condyles were shorter, thicker, tipped more anteriorly and positioned more posteriorly [the proportions of post-positioned condyles of low angle, average angle and high angle patients were 26%, 4%, 0% respectively].

CONCLUSIONSClass II division 1 adolescents with different vertical skeletal patterns had different forms of fossae, and different positions and forms of condyles.

Adolescent ; Cone-Beam Computed Tomography ; Humans ; Malocclusion ; Malocclusion, Angle Class II ; Mandibular Condyle ; anatomy & histology ; Temporal Bone ; Temporomandibular Joint ; anatomy & histology ; diagnostic imaging

OBJECTIVE: To present the experience of nasal reconstruction with forehead flap. METHOD: nasal reconstruction with forehead flap were applied in eight nasal carcinoma cases after operation and 5 nasal trauma cases with defects. RESULT: These forehead flaps were alive in all patients, all incision healed in I stage, no post operative complications were found. The shapes of nose were satisfactory, there were no recurrence of tumor during 1 to 17 year follow up. CONCLUSION The method can be clinically applied for its simple procedure, reliable flap's blood supply, high survival rate and satisfied result.
Adolescent ; Adult ; Aged ; Female ; Forehead ; surgery ; Humans ; Male ; Middle Aged ; Nose ; injuries ; surgery ; Rhinoplasty ; methods ; Skin Transplantation ; Surgical Flaps ; Young Adult

OBJECTIVETo investigate the effect of clostridium difficile toxin A(TcdA) on the Rho GTPases and the cytoskeleton in K562 cells.

METHODSK562 cells were cultured in vitro with different concentration of TcdA.The effect of TcdA proliferation of cells was detected by MTT method after the K562 cells were stimulated with TcdA for 24,48 and 72h; the expression of cdc42, RhoA, Rac1 mRNA was assessed by RT-PCR; the changes of the microtubule, the microfilament were observed by confocal laser scanning microscopy.

RESULTSThe proliferation of K562 cells was inhibited after exposure to TcdA for 24, 48 and 72h, and the inhibitory rate was 47.67% in the treatment for 48 h. the cdc42，RhoA and Rac1 mRNA expressions in the experimental groups decreased after treated with TcdA(P<0.05), which positively correlated with concentration of TcdA. Also, the microfilament decreased ,which was observed by confocal laser scanning microscopy.

CONCLUSIONTcdA inhibites K562 cell proliferation and induces apoptosis, TcdA can change the cytoskeleton structure through the cytoskeletal protein genes cdc42 and RhoA, Rac1 mRNA expression,. It is related with cell microfilament content decreasing.

Objective: To examine the prevalence and trend of tobacco and e-cigarettes uses and identify the influencing factors for smoking behavior in junior middle school students in Shanghai, and provide data support and scientific basis for the development of tobacco control intervention strategy in adolescents. Methods: Multi-stage stratified random sampling method was used to select junior middle school students in 8 districts and 10 districts in Shanghai in 2013 and in 2019 respectively. Information about tobacco and e-cigarettes uses in the students were collected by using self-administrated questionnaire. The prevalence of tobacco and e-cigarettes uses were calculated, the difference between two years was compared with χ² test. The influencing factors were identified by multivariate logistic regression analysis. Results: In 2019, the current smoking rate was 0.6% in junior middle school students in Shanghai, and the smoking attempt rate was 2.9%, both were lower than the levels in 2013 (0.7% and 6.9%). The current use rate of e-cigarettes was 0.6% in 2019,with no significant change compared with 2013 (0.6%). The proportion of the students who had heard of e-cigarettes in 2019 (78.4%) was higher than that in 2013 (47.2%). In 2019, the second-hand smoke (SHS) exposure rate at home, in both indoor and outdoor public places and on public transportations was 72.5%, which was slightly lower than the level in 2013 (73.0%), the differences were all significant (P<0.05). In 2019, the students seeing close friend smoking (OR=27.381, 95%CI: 12.037-62.287), seeing someone smoking in school (OR=2.477, 95%CI: 1.155-5.312), believing that SHS may not be harmful (OR=8.471, 95%CI: 1.464-49.005) had higher possibility of smoking. Being aged ≥15 years (compared with being aged ≤12 years, OR=8.688, 95%CI: 1.922-39.266), exposure to SHS in outdoor public place (OR=8.608, 95%CI: 1.048-70.692), close friend smoking (OR=8.115, 95%CI: 1.754-37.545) were positively associated with e-cigarettes use, and believing that smoking results in uncomfortable social contact [compared with believing that smoking results in comfortable social contact (OR=0.105,95%CI: 0.018-0.615)] were negatively associated with e-cigarettes use, the difference was significant (P<0.05). Conclusion: The prevalence of tobacco and e-cigarette uses in junior middle school students in Shanghai remained at a low level in recent years. The SHS exposure rate in junior middle school students is high. Smoking behavior of junior middle school students is closely related to personal attitude and awareness of tobacco, exposure to SHS, peer smoking and the situation of tobacco control in schools. Prevention and intervention should be carried out from multi-dimensions to effectively protect teenagers from tobacco hazards.
Adolescent ; China/epidemiology* ; Electronic Nicotine Delivery Systems ; Humans ; Prevalence ; Students ; Tobacco ; Tobacco Smoke Pollution