Objective：To establish model of dental pulp cells with activated Notch signaling pathway, and investigate the effect of activating Notch signaling pathway on senescence of human dental pulp cells in vitro. Methods: Human dental pulp cells were isolated, cultured as usual, and used from the 4^th passage. The cells were divided into the activated group and the negative control group. In the activated group, the way of coating dishes with Jagged1 protein (10 mg/L) was used to activate Notch signaling pathway. The negative control group cells received no treatment. In the 4^th, 8^th, and 10^th passages, the expression levels of the Notch signaling pathway downstream gene Hes1 were verified by real-time quantitative PCR (RT-qPCR). The cell changes after activating Notch signaling pathway were observed at three levels: (1) The cell morphology changes were observed through invert phase contrast microscope. The cell activity was detected with MTT assay. (2) The alkaline phosphatase (ALP) expression and its activity, and senescence-associated β-galatosidase (SA-β-Gal) expression were observed with the kit. (3) The expression changes of senescence related genes were verified using RT-qPCR. The difference between the negative control group and the activated group was analyzed using student’s t test. Results: The expression level of the downstream gene Hes1 of Notch signaling pathway increased after coating the dishes with Jagged1 protein, indicating the establishment of the model of dental pulp cells with activated Notch signaling pathway. Compared with the negative control group, the aging cells of the activated group appeared relatively late. In the 8th and 10th passage, the cell activity increased. In the 10th passage, ALP activity increased, but SA-β-Gal expression decreased. p16 gene expression decreased in each passage, and p53 gene expression decreased in the 8th and 10th passages. Conclusion: Jagged1 could activate Notch signaling pathway effectively. Through activating Notch signaling pathway, the dental pulp cells showed a trend of senescence delay at different levels, such as cell morphology, metabolic enzyme expressions and related gene expressions.

Objective： To get the stem cells from the young permanent tooth apical papillae, and observe the osteogenic differentiation of the cells after cultured with acellular dermal matrix (ADM). Methods: Young permanent tooth apical papillae were obtained by the oral surgeon. The cells from the apical papillae were isolated, cultured and analyzed through a flow cytometer. The cells in the experimental group were induced both osteogenic and adipogenic differentiation. The cells were not induced in the control group.Both groups were evaluated by staining and real-time polymerase chain reaction (real-time PCR) to examine the quantity of RNAs in the experimental group. The cells from apical papillae were also cultured with ADM. These cells were also induced both osteogenic and adipogenic differentiation in the experimental group, and not induced in the control group. The measures of staining and real-time PCR were also carried out. Results: The cells from the apical papillae proliferated in a rapid rate. Of which 70.3% in cultures were positive for Stro-1, and 96% positive for CD105 according to flow cytometric analysis. After induction, the RNA level related to osteogenic and adipogenic differentiation expressed higher in the experimental group than those of the control group without induction obviously, such as osteocalcin (OCN)， bone sialoprotein (BSP), liver X-recepter α (LXRα)， lipoprotein lipase（LPL）， peroxisome proliferator activated receptor γ (PPAR-γ)， and scavenger receptor class B type 1（SR-B1）. The cells cultured with ADM also had a fast proliferation, and grew attached to ADM. After induction, the RNA level of OCN and BSP had a higher expression than the control group (P>0.05), and LPL also expressed higher (P<0.05). Conclusion: The study approved that there were a big amount of stem cells in the young permanent tooth apical papilla obtained by oral surgery, which had significant osteogenic potential. The cells still proliferated well when they were cultured with ADM as a kind of collagen skelecton. The results showed that ADM could be performed as a base to support the stem cells to survive the environment, and it also could play a role in osteogenic differentiation of stem cells from apical papilla.

Objective：To evaluate the effects of the microstructure of mineralized collagen scaffolds on cell morphology of MG 63. Methods:The extrafibrillarly mineralized collagen (EMC) and intrafibrillarly-mineralized collagen (IMC) scaffolds were fabricated separately by a conventional mineralization approach and a biomimetic, bottom-up mineralization approach. Scanning electron microscopy (SEM) was employed to examine the microstructure of the mineralized collagen scaffolds and cell-scaffold interactions. The effects of the mineralization methods on cell adhesion to the surface of the collagen scaffolds were analyzed by laser scanning microscope (LSM). Results:The two mineralized collagen scaffolds exhibited different microstructures, including the size, morphology and location of the apatites in collagen nanofibers by SEM imaging. In the EMC scaffold, flower-like aggregates randomly deposited around the collagen nanofibers, while no apatite was observed on the surface of the nanofibers. The presence of an intrafibrillar apatite mineral phase in the IMC scaffold was confirmed using energy dispersive X-ray spectroscopy (EDS) coupled to SEM, with the Ca ∶P ratio of approximately 1.48.This chemical composition was similar to natural bone tissue. The LSM results showed that the IMC scaffold could promote cell spreading compared with the EMC scaffold. Furthermore, the cells cultured on the IMC scaffold (18.54±2.71) showed higher density of vinculin staining than those on the EMC scaffold (14.29±1.32). From the SEM examination, both mineralized collagen scaffolds showed good biocompatibility. However, the cells exhibited different morphology on different scaffolds. Conclusion:The microstructure of the mineralized collagen scaffolds can affect the initial cell adhesion and morphology. Furthermore, the IMC scaffold can promote cell adhesion and spreading. The present study will help us to fabricate novel biomimetic materials for alveolar bone regeneration.

Objective：To identify Streptococcus mutans (S. mutans) in carious patients’ saliva using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS), and to establish a faster and more accurate method to identify S. mutans. Methods:In this study, a total of 90 carious patients from Department of Endodontics of Peking University School of Stomatology were recruited. All these patients’ saliva was collected. After extracting the protein of the samples, they were identified by MALDI-TOF MS. The composite profile was analyzed using BioExplorer 1.0 software. The scores≥25 were considered as S. mutans, whereas the scores <25 were as considered as non S. mutans. Finally, these results were compared with 16S rDNA sequencing to figure out the sensitivity and concordance rate, respectively. Results:The sensitivity of MALDI-TOF MS was 96.0%, and the concordance rate compared with 16S rDNA sequencing was as high as 98.7%. Conclusion:MALDI-TOF MS is high throughput, rapid and easy to perform in comparison to other conventional methods. It has a high sensivity and concordance rate. Thus, MALDI-TOF MS can serve as an effective tool for identification of S. mutans.

Objective：To evaluate the effects of a commercial bleaching agent containing 35% (mass fraction) hydrogen peroxide on the growth of Streptococcus mutans biofilm on enamel disc surface. Methods:A total of 20 enamel disks were made from human extracted teeth and the enamel surfaces were kept intact. The discs were autocalved and randomly divided into two groups: bleaching group and control group. Each group contained 10 discs. For bleaching group, the enamel discs were whitened by commercial 35% hydrogen peroxide according to the instruction (Beyond^TM Professional Dental Whitening Kit, Beyond Technology, TX,USA ); no treatment for control group. All the discs were kept in sterile human saliva for 3.5 hours, and then the mixture of brain heart infusion broth (BHI) medium and Streptococcus mutans were added. The discs and Streptococcus mutans were incubated together in BHI medium with 5% CO₂ (volume fraction), at 37 ℃. After 3, 7, 14, 21 and 28 d’s incubation, two discs of each group were taken out and the biofilms on the enamel surfaces were evaluated by using conventional bacteria counts and confocal laser scanning microscope (CLSM). The bacteria in the biofilm on one disc enamel surface were analyzed by plating on BHIS agar and the colony-forming units were counted. The biofilm on the other disc surface was stained using a twocolour fluorescent dye kit (Bacerial Viability Kit L-7012) for CLSM. Results:The vital bacteria counts of vital cells in the 3, 7, and 14 d’s biofilms of the bleaching group were significantly fewer than those of the control group. Especially in the 3 days’ biofilm on the whitened surface, the vital bacteria counts ［(3 595±2 903) μm² vs. (89 155±65 963) μm²，t=8.71，P=0.00］ and proportion of vital bacteria ［(26.0%±16.4%) vs.(92.2%±10.9%)，t=19.93，P=0.00］ were significantly fewer than those of the control. While, for the 21d’s biofilm, the vital bacteria counts and the percentage of the vital cells of the bleaching group were more than those of the control group significantly ［(66 262±23 772) μm² vs. (51 184±20 502) μm²，t=2.59，P=0.012］.Conclusion:The hydrogen peroxide-containing bleaching agent may inhibit the growth of Streptococcus mutans biofilm for about 3 weeks; but after 3 weeks, it seems that the bleached surface will increase the growth of biofilm. Whether the whitening therapy will increase caries susceptibility of the bleached surface needs further research.

Objective： To retrospectively evaluate the efficiency of dental treatment under general anesthesia (GA) in child patients, and analyze the related factors. Methods: The records of patients treated under GA in the Department of Pediatric Dentistry, Peking University School and Hospital of Stomatology, between Aug 2008 and Jun 2012 were collected and analyzed. Two hundred and twenty eight records were found, of which 111 patients under 18 years old who were recalled more than 3 months after GA were selected randomly. The unplanned treatments including caries, failed restoration, root canal treatment and space maintenance fall-off etc. were recorded and analyzed. The survival rate and median survival time of the teeth were calculated, and a multivariate analysis was performed by Cox proportional hazard model. Results: Totally, there were 1 415 teeth treated under GA. The median survival time was 825 days, 77.0% of the teeth were present during their recall period. The median time of the first unplanned treatment was 215 days, and the failed restoration was the main reason for the unplanned treatment. Other factors such as the age at treatment, gender, total number of decayed teeth, reason for GA, and living place were found unassociated with the survival rate. Conclusion: The effect of dental treatment under GA is satisfied. Regular dental visit after GA is very important for children’s dental health.

Objective： To explore the clinical application of endoscope-assisted operative retrieval of large parotid stones as a minimally invasive alternative.Methods: From January 2010 to April 2013, 6 patients (male: 5, female: 1, age from 30-62 years, and median age: 49.5 years)suffering from recurred swelling of parotid gland due to sialoliths were treated by endoscope-assisted parotid surgery in Peking University School and Hospital of Stomatology. All of the patients underwent clinical, ultrasonographic and cone-beam CT (CBCT) examinations to get the detailed information of the number, location and size of stones, which was recorded in the medical records. Endoscope-assisted parotid surgery was performed under general anesthesia in all the 6 cases after the failure of basket or forcep retrieval firstly. During the operation, sialoendoscope was used to locate the stone exactly and then the calculus was exposed through a pre-auricular approach and released by incising the duct. The postoperative complications were recorded and observed during the follow-up periods.Results: Preoperative radiological examinations showed that all of the sialoliths were near the hilum of parotid gland ducts in the 6 cases, which were 5-9 mm in diameter. All of the stones were removed successfully by endoscope-assisted operative retrieval. The incisions healed smoothly in all the 6 cases. There were no cases of facial nerve weakness, infection or salivary fistula. After a mean follow-up of 19 months (ranging from 6-36 months), 5 patients remained asymptomatic and 1 patient had mild obstructed or infective symptoms. The final results were satisfied.Conclusion: It is suggested that endoscope-assisted operative retrieval is a viable minimally invasive alternative to remove the large or recalcitrant parotid stones with a high successful rate and low complications.

Objective：To give a reference for the early diagnosis and treatment of the cysts arising from the temporomandibular joint. Methods: Nine patients finally diagnosed as temporomandibular joint cysts at the Peking University Hospital of Stomatology from May 1998 to August 2013 were selected and reviewed. Their clinical manifestations, imaging features, diagnoses and differential diagnoses, treatments and followups were summarized and discussed. Results: In the 9 patients, 3 were males and 6 females. Their ages ranged from 33 to 62 years with a median age of 39 years; the course of the disease ranged from 2 weeks to 3 years with a median of  4 months. The image examinations were performed with conventional X-ray examinations in 7 cases, CT scans in 8 cases, MRI in 6 cases and ultrasound in one case. Of the 9 cases, 7 were finally diagnosed as ganglion cyst and 2 as synovial cyst. Ganglion cysts mainly presented as the mass of preauricular area or joint area, with no obvious symptoms or only local discomfort, occasionally with pain. The synovial cysts manifested as the painful swelling of preauricular area and limited mouthopening, accompanying with occlusal disorders. The treatments included surgical resection in 8 cases, repeated arthrocenteses and lavages in one case. The follow-ups were from 3 months to 9 years, one case with recurrence, and the remaining eight cases without recurrence. Conclusion: MRI examinations are very helpful in the early diagnosis and treatment planning of temporomandibular joint cysts. Surgical resection can have good results. Repeated arthrocenteses and lavages also have a good result, which may be an alternative choice for synovial cyst, but more accumulation of clinical experience is further needed.

Objective：To analyze the benefits of facial nerve electromyographic monitoring during parotid tumor surgery.  Methods:In the study, 92 patients with parotid tumor who underwent surgery were surveyed. The study group consisted of 46 patients who underwent intraoperative electromyographic monitoring, and 46 patients served as the control group. The incidence of postoperative facial nerve weakness and the operation time were recorded.Results:In the primary parotid tumor resection，the operation time of the study group (6 cases)was (50.0±9.1) min, that of control group (7 cases) was (42.9±5.2) min (P=0.064) when the facial nerve needed no dissecting; the operation time of the study group (32 cases)was (74.7±28.0) min, that of control group (33 cases) was (75.6±29.8) min (P=0.893) when the facial nerve needed dissecting. For the patients with revision surgery, the mean operation time in the study group ［(117.5±37.8) min］ was significantly lower than that of the control group ［(175.0±47.8) min］, P<0.05. In the study group, 8 patients suffered from postoperative facial nerve weakness because of tumor characteristics; in the control group, 6 patients suffered from postoperative facial nerve weakness, with 4 cases because of tumor characteristic, and 2 cases  because of operator error.  Conclusion:The results suggest that continuous electromyographic monitoring of facial nerve during parotidectomy reduces the mean operation time in patients with revision surgery, but not the incidence of postoperative facial paralysis.

Objective： To investigate the influence factors on the surface roughness and staining susceptibility of infiltrant resin. Methods: In the study, 30 human third molars were used, and each sample had three open enamel windows. The samples were randomly divided into three groups according to their different demineralized time. Each sample had at least one intact spot (A), one infiltrant resin spot (B) and one artificial white spot lesion (C). The surface roughness was tested before color staining for all the three spots of each specimen. The specimens were stored in a staining solution (coffee) for a period of 21 days, before and after which the color Commission Internationaled’ Eclairage (CIE)L*a*b* was recorded for A, B and C spots.Results: The B spot’s surface roughness of each group was（0.15±0.02）μm,（0.31±0.03）μm and（0.40±0.02）μ m, respectively. And the C spot’s surface roughness each was（1.08±0.10）μm，（2.89±0.13）μm and（3.41±0.14）μm. The surface roughness of B and C of the three groups increased with demineralization time longer, and had significant difference for both B and C (P<0.01). The ΔE of the three groups between A and B before staining had significant difference (P<0.01). And the ΔE of group1 was less than 3.7, but the other two groups’ more than 3.7. After staining, the ΔE of groups 1 and 2 was less than 3.7 but that of group 3 was more than 3.7. There were significant differences between groups 1 and 3, and also between groups 2 and 3(P<0.01).Conclusion: The degree of the lesion’s demineralization has effect on the surface roughness and color susceptibility of infiltrant resin. The increased surface roughness of infiltrant resin has positive effect on masking enamel white spots.

Objective：To compare the clinical effectiveness of the two-step etch-and-rinse with the one-step self-etch adhesive in non-carious cervical lesions. Methods: Fifty patients were selected, each with at least two wedge-shaped defects in the mouth. The paired defects were randomly bonded either with the two-step etch-and-rinse adhesive α or the one-step self-etch adhesive β and then restored with resin composite. The treatment was carried out by one practitioner according to standard procedures. The evaluation was performed by another practitioner according to modified United States Public Health Service (USPHS) criteria at one week, six months and eighteen months after treatment. Chi-square test was used for statistical analysis. Results: Fifty restorations were placed for each group. Forty-eight patients attended the six months recall, with two restorations loss for each group. Forty-four patients attended the eighteen months recall, with accumulative four restorations loss for adhesive α and six restorations loss for adhesive β. The retention rate was 90.0% for group α and 86.4% for group β. Marginal adaptation of three restorations in group α and five restorations in group β were scored Bravo; while for marginal discoloration, two restorations in group α and three restorations in group β were scored Bravo respectively. No secondary caries and post-operative sensitivity occurred for any of the restorations after eighteen months. No significant difference was detected between the groups for any evaluation criteria (P>0.05). Conclusion: Within the observation period of this study, the two-step etch-and-rinse adhesive and the one-step self-etch adhesive showed similar clinical performance. The long term follow-up is still warranted.

Objective：To evaluate the influence of different alveolar bone heights on fracture resistance and pattern of post and core restored maxillary premolars. Methods:Forty-eight maxillary premolars were randomly divided into 6 groups (8 teeth in each group) for different alveolar bone heights and different post and core materials. Group A: fiber post and core and normal alveolar bone height. Group B: Ni-Cr cast post and core and normal alveolar bone height. Group C: fiber post and core with 2 mm alveolar bone height reduction. Group D: Ni-Cr cast post and core with 2 mm alveolar bone height reduction. Group E: fiber post and core with 4 mm alveolar bone height reduction. Group F: Ni-Cr cast post and core with 4 mm alveolar bone height reduction. All of the teeth were restored with Ni-Cr cast crowns. Fracture resistances were tested and the failure modes were examined. Results:The mean fracture resistances were (762.49±84.91) N for group A, (794.26±72.61) N for group B, (517.69±80.30) N for group C, (543.50±62.88) N for group D, (219.91±43.20) N for group E, and (196.16±41.08) N for group F. The ratios of favorable fractures were 100.0% for group A, 37.5% for group B, 75.0% for group C, 12.5% for group D, 50.0% for group E, and 0 for group F. Conclusion:The alveolar bone height has a significant impact on fracture resistance and modes of post and core restored maxillary premolars. With the reduction of alveolar bone height, the fracture decreases and the fracture mode tends to be unfavorable.

Objective：To evaluate the relationship of incisal point displacements in the mandibular retruded contact position (RCP) between the self-controlled retruded approach and bimanual manipulation method. Methods: Twelve healthy young volunteers were selected. The RCP was guided through the self-controlled retruded approach and bimanual manipulation method. The track of the incisal point was recorded, using the mandibular movement trace recording system. The movement direction of the incisal point in horizontal plane was observed. The distance between the incisal point of the RCP and intercuspal contact position (ICP) was measured.Results: Except one volunteer’s incisal point movement direction of the RCP was oblique, others were straight toward posterior. The displacements of the incisal point from the ICP to RCP guided through self-controlled approach and bimanual manipulation method were (1.15±0.64) mm, (0.98±0.29) mm respectively. There was no statistical significance between the two methods (P>0.05).  Conclusion: The displacements of the incisal point from the ICP to RCP guided through selfcontrolled approach and bimanual manipulation method are approximately the same.

Objective：To study the fracture resistance and characteristics of the bi-layer zirconia all ceramic crowns according to the zirconia coping design using various experimental methods and to compare the results of the in vitro test with the clinical evaluation. Methods:The bi-layer zirconia all ceramic crowns were fabricated by the same method as used in clinical practice. Two different coping designs with/without zirconia marginal collar were used. All the samples were cemented onto corresponding resin dies. All the specimens were tested in the 2 groups with/without zirconia collar. The fracture load test was performed on 10 crowns from each group. Fracture strength was tested with a universal testing machine. The fracture modes and features of the failed crowns were observed with an integrated microscope and a field emission scanning electron microscope. Results:The zirconia collar group showed higher fracture load than the group without zirconia collar. All the zirconia crowns failed with porcelain failure and without zirconia coping broken. The porcelain fracture modes were crack, chipping and delamination. The distribution of the different fracture modes in the groups was the same. Conclusion:The bi-layer zirconia crown with 2 mm zirconia marginal collar showed more fracture strength under once load. The fracture modes of the test specimens were the same as the clinical fracture bi-layer zirconia crowns, showing porcelain chipping and delamination.

Objective：To evaluate and compare the measurement accuracy of three facial scanners, based on different scanning principles: line laser, structured light and stereophotography. Methods：Three-dimensional (3D) digital face models of the same plaster head model were obtained by three facial scanners separately. The measurement values of the length of 10 feature lines and the angle of 5 feature angles were measured on these 3D models in the software respectively. The standard values of these characteristics were measured by a coordinate measure machine (CMM) with high accuracy. Statistical and surveying analyses were made between the measurement values and standard values. Facial morphology theory measurement accuracy of these three facial scanners was obtained finally. Results：There was no statistical significant difference between the measurement values from the three facial scanners and the standard value from CMM. The 3dMD and Faro scanners were better in length measurements and the length measurement accuracy was about 0.2 mm. The Faro scanner was also better in angle measurements and the angle measurement accuracy was about 0.5°. Conclusion： The three facial scanners all have good reliability in facial measurements, and their actual measurement accuracy for patients needs further research.

Objective：To compare the fracture resistance of endodontically-treated teeth restored with prefabricated zirconia posts or one-piece computer aided design and computer aided manufacture (CAD/CAM) zirconia posts and cores, and unrestored endodontically-treated teeth. Methods: Recently extracted human maxillary central incisors (n=36) were endodontically treated and divided into three groups (n=12 each): group 1 was restored with prefabricated zirconia posts (Comospost) and hot pressed ceramic cores; group 2 restored with one-piece CAD/CAM zirconia posts and cores; group 3 not restored. The teeth were fixed in a universal load-testing machine; a compressive load was applied at 135 degrees to the long axis of each tooth at a crosshead speed of 1 mm/min until fracture. One-way analysis of variance (Student-Newman-Keuls) was used to determine the significance of the differences in failure load between the groups.Results: The mean fracture loads were (311.75 ± 70.12) N, (423.83 ± 54.58) N and (736.33 ± 82.91) N, respectively. The unrestored teeth exhibited significantly higher fracture resistance than the two groups of restored teeth. The teeth restored with one-piece CAD/CAM zirconia posts and cores had higher fracture resistance than the teeth restored with prefabricated zirconia posts and hot pressed ceramic cores (P < 0.001). Conclusion: Within the limitations of this study, the root canal-treated teeth restored with one-piece CAD/CAM zirconia posts and cores had a significantly higher failure resistance than the teeth restored with prefabricated zirconia posts. One-piece CAD/CAM zirconia posts and cores can offer some advantages for esthetic prosthodontics.

Objective：To build up and validate a system based on gyroscope to record human natural head position (NHP) and to transfer it into virtual surgical design system. Methods:Three dimensional (3D) mechanical gyroscope and 3D design software were integrated in the system. The protocol for recording and transforming NHP included four steps. Firstly, the gyroscope was CT scanned when its position was (0, 0, 0), a virtual model was built up by 3D reconstruction and considered as standard gyroscope model. Secondly, the gyroscope was bounded to the patient’s head using bite-jid and face bow. The NHP was recorded when the patient was looking himself into mirror. Thirdly, the virtual head of the patient was overlapped with standard gyroscope model. Finally, when pitch, roll and yaw of NHP were applied to the compound model, the virtual head was orientated to NHP. A standard cube model was used to validate the accuracy of the system. The cube was positioned 30 times, the real and virtual pitch, roll and yaw angles were recorded. The accuracy of the system was presented by the mean±SD of the Delta. the difference between the real and virtual pitch, roll and yaw angles were analyzed by paired t test，and their correlations were investigated by Pearson test. Results:The accuracy rates of the system were ΔPitch＝0.03± 0.28°,ΔRoll=0.03±0.23°,ΔYaw=0.07±0.49°. There were no significant differences between the real and virtual pitch, roll and yaw angles (P>0.05). The two positions were absolutely correlated at the level of α=0.01 (2tailed, r=1.00). Conclusion: The method of recording and transforming NHP using gyroscope is clinically applicable. The accuracy of transferring system meets the needs of virtual surgical design.

Objective： To explore a new method of patient-involved digital design, esthetic outcome prediction and fabrication for the esthetic rehabilitation of anterior teeth, and to provide an alternative choice for the restoration of anterior teeth. Methods: In this study, 32 patients with esthetic problems in their anterior teeth were included and divided into two groups randomly: the experimental group (16 patients) and control group (16 patients). In the experimental group, the dentition and facial images were obtained by intra-oral scanning and three-dimensional (3D) facial scanning and then calibrated. The design of the rehabilitation and the esthetic outcome prediction were created by computeraided design (CAD) software. After morphologic modification according to the patients’ opinions, prostheses were fabricated according to the final design by computer-aided manufacturing (CAM) equipment. As for the control group, the regular design method was applied to restore their anterior teeth. The time consuming in the first insertion of each restoration in both groups was recorded. The quality of the prostheses was assessed by another prosthedontist. The satisfaction to prostheses and the facial appearance were evaluated by the patients. Results: The process of the patient-involved digital design and outcome anticipation was successfully established. The patients were satisfied with the esthetic effects of the anterior restoration made by the digital technique. The acceptance rate of the patients on the digital rehabilitation in the experimental group was 100%. There was no significant difference of the quality of the prostheses between the two groups. The satisfaction rate of the patients on prostheses and facial appearance was significantly higher in the experimental group than in the control group (P<0.05). In addition, the time consuming in the first insertion of the experimental group was much shorter than that in the control group (P<0.01). Conclusion: The new method of the patient-involved digital design, esthetic outcome prediction and fabrication for the esthetic rehabilitation of anterior teeth is a practical technique. This method is useful in shortening the time consuming of the restoration of anterior teeth and improving the patient satisfaction with the esthetic outcome.

Objective：To investigate the root canal configuration of mandibular anterior teeth with cone beam computed tomography (CBCT). Methods: The CBCT imaging data of 866 patients who visited Peking University School of Stomatology from October 2012 to July 2013 were inspected by an endodontist anda radiologists together. A total of 4 674 mandibular anterior teeth were involved. The number of root, root canals and root canal configuration were observed and analyzed statistically (Chi-squared test). Results: All the mandibular central incisors and lateral incisors were single root, and 0.7% (11/1 542) of canines were double roots. 6.7% (105/1 566) of central incisors, 17.4% (273/1 566) of lateral incisors and 3.0% (46/1 542) of canines had double root canals. The frequency of symmetry of double root canal was 58.7% (37/63) in central incisors, 76.1% (108/142) in lateral incisors and 29.6% (8/27) in canines. The highest frequency of double root canals in different ages was 9.8% (28/287, 31-40 years) in central incisors, 21.5% (61/284, 31-40 years) in lateral incisors and 9.2% (19/207, ≥ 51 years) in canines. Vertucci type Ⅲ canal configurations were the most prevalent in mandibular anterior teeth. Conclusion: The double root canals are most common in mandibular lateral incisors. The highest incidence of symmetry of double root canal is also observed in mandibular lateral incisors. Vertucci type Ⅲ canal configurations are the most frequent type in mandibular anterior teeth.

Objective：To collect and analyze the three-dimensional (3D) facial profile variation of edentulous patients restored by complete denture. Methods: The 3D facial images of 20 Atwood Class Ⅱ edentulous patients were taken by DSC-2 3D facial imaging system before and after restoration of complete denture．Then, the two 3D facial images of each patient before and after restoration were registered in the same coordinate system by partial structure overlap. The differences between these two 3D facial images were statistically analyzed. Results: The major facial profile variation of Atwood Class Ⅱ edentulous patients restored by complete denture focused in the area around the upper lip and the corner of the mouth. The change of lower lip and chin area was not obvious. The shift in the sagittal direction was significantly more evident than that in the vertical direction, while the shift in the horizontal direction was the least one. Conclusion: The pattern of facial profile variation of edentulous patients restored by complete denture based on 3D imaging may provide reliable data support for prediction and communication in clinical practice.

Objective： To compare the effects between dezocine and flurbiprofen axetil on postoperative sore throat (POST) after maxillofacial procedures. Methods: In the study, 90 adult patients with maxillofacial diseases were divided randomly into control group (group C), flurbiprofen group (group F) and dezocine group (group D). Physiological saline, flurbiprofen axetil (1 mg/kg) and dezocine (0.1 mg/kg) were administered intravenously for each group 30 minutes before the end of the operation. We recorded visual analogue scale (VAS) and Bruggrmann comfort scale (BCS) at the time points of 0.5 h, 1 h, 2 h, and 6 h after extubation. Results: The incidence of POST in group D decreased significantly (P<0.05). There was no difference between the incidences of groups F and C. The VAS of group F was lower than that of group C (P<0.01) just at the time points of 0.5 h and 1 h after extubation, from then on, there was no difference between the 2 groups. The VAS of group D was lower than that of group F, and the BCS was higher than that of group F significantly. Conclusion: Dezocine has notable analgesia effect for postoperative sore throat, so it is a better choice to carry out postoperative analgesia after maxillofacial procedures.

Objective：To evaluate the effect and safety of propofol target controlled infusion (TCI) with a small dosage of fentanyl intravenous sedation on the removal of the third impacted molar tooth. Methods: In the study, 58 ASA (American Society of Anesthesiology) Ⅰ-Ⅱ patients with impacted wisdom tooth removal (age: 18-45 years), were divided into two groups: control group (n=26) received 40 mg lidocaine+propofol TCI; experimental group (n=32) received 0.8 μg/kg fentanyl+propofol TCI. The complete evaluating indexes were recorded, and the data compared and analyzed. Results: The differences of the gender, age, weight, operation time and sedation time were not significant. The heart rate and bispectral index of the experimental group on local anesthesia injection were significantly lower than those of the control group (P<0.05). Other differences on heart rate, mean blood pressure, pulse oxygen saturation, respiration rate and bispectral index between the two groups were not significant during operation. The differences on recall of local anesthesia injection, incision and drilling between the two groups were not significant. The pain caused by the propofol injection, and the body movement caused by local anesthesia injection and talkativeness during operation in the experimental group were significantly lower than those in the control group (P<0.05). No patient in the two groups had nausea and vomiting. After discharge, 19 patients in the experimental group (19/32), 14 patients in the control group (14/26) were sleepy after coming home. The difference of the patient’s satisfaction between the two group was not significant, but the patient’s satisfaction was significantly higher than the doctor’s (P<0.05), and the doctor’s satisfaction in the experimental group was significantly higher than that in the control group (P<0.05). Conclusion: Propofol TCI with a small dosage of fentanyl intravenous sedation on the removal of impacted wisdom tooth is effective and safe. Both patients and doctors have high degree of satisfaction on it.

Objective：To assess the characteristics of establishing the different sample banks of plasma, leukocytes and DNA by sedimentation method of isolating from ethylene diamine tetraacetic acid（EDTA）-blood and to clarify the sedimentation method of leukocyte isolation and plasma volume by comparative data and recommended procedures for applicability. Methods:In the study, 29 EDTA-bloods were obtained, the total amounts of leukocytes and the percentage of neutrophile granulocytes, and lymphocytes in the EDTA-blood detected as a control group and then assigned equally into 4 EP tubes with 1 mL EDTA-blood per tube as 4 test groups, then the 4 tubes were placed with the EDTA-blood at room temperature and the plasma layers were isolated at 0.5, 1, 2 and 3 h, receptively. The total amount of leukocytes and the percentage of neutrophile granulocytes, and lymphocytes were detected by automated hematology analyzer at the clinical laboratory. The volume of the plasma was also measured at the same time. Results:The plasma volume at 0.5 h ［(241.72±101.52)μL］ was substantially lower than those at 1 h［(317.24±97.50)μL］, at 2 h［(371.03±91.66)μL］, and at 3 h ［(408.97±97.43)μL］ , P<0.05. The plasma volume at 1 h was substantially lower than those at 2 h and 3 h (P<0.05). The total amount of leukocytes in the plasma layer at 0.5 h (2.50 ×10⁶±1.48×10⁶) group was substantially higher than the amount of 2 or 3 h groups respectively (1.47×10⁶±7.19×10⁵ ,1.21 ×10⁶±7.41×10⁵), P<0.05. Significant difference was not found between 0.5 h group and 1 h group (2.29×10⁶±1.17×10⁶) , P>0.05. The total amount of leukocytes in the plasma layer in1h group was substantially higher than that in 2 h and 3 h groups (P<0.05). There was no significant difference between 3 h group and 2 h group (P>0.05). The total amount of leukocytes in the plasma layer of the 4 test groups was substantially lower than that in the control group (P<0.05). The percentage of neutrophile granulocytes (54.14%±11.65%) in the plasma layer in 0.5 h group was substantially higher than those in 1 h, 2 h and 3 h groups (46.66%±12.70%，39.17%±12.33%，43.25%±14.54%), P<0.05, respectively, which was the substantially lower than that in the control group (60.53%±8.46%), P<0.05. The average value of the percentage of neutrophile granulocytes in the plasma layer in 1 h group was substantially higher than that in 2 h group (P<0.05). There was no significant different between 3 h group and both 1 h, 2 h groups (P>0.05). The mean percentage of lymphocytes in the plasma layer in 0.5 h group (35.09%±10.84%) was substantially lower than those in the plasma layer in 1 h, 2 h and 3 h groups, respectively ( 41.48%± 12.20%, 47.96%±12.27%, 45.50%±13.71%), which was significant higher than that in the control group（30.98%±7.33%), P<0.05. The average value of the percentage of lymphocytes in the plasma layer in 1 h group was substantially higher than those in the control group and 0.5 h group, but was substantially lower than those in 2 h and 3 h groups (P<0.05). The average value of percentage of lymphocytes in the plasma layer in 2 h group was substantially higher than those in the control group, 0.5 h and 1 h groups (P<0.05). There was no significant difference between 2 h and 3 h groups (P>0.05). Conclusion:The best period of time in obtaining leukocytes is 0.5-1 h sedimentation of EDTA-blood. Both the plasma layer and leukocytes can be separated and obtained at the same time from the same sample by the sedimentation method of EDTA-blood. The sedimentation of EDTA-blood has the least interference of both chemical and physical factors, as well as a ready operation, which can establish the plasma, leukocytes and DNA sample banks for various aspects of research.

Objective：To explore the functional different natural killer (NK) cell subsets through the expression of killer immunoglobulin receptor (KIR) and CD57 on NK cells. Methods: From May 2012 to June 2012, the peripheral blood samples of 10 related healthy donors for hematopoietic stem cells transplantation were collected to analyze KIR, CD57 expression and the intracellular cytokines of interferon-γ(IFN-γ), and the CD107a secreted by NK cells through 6-colour flow cytometer to compare the cytokine secretion and cytotoxic function among different NK subset. Results: The expression of CD57 on NK cells were significantly higher than those of KIR on NK cells［(60.71%±5.71%) vs. (24.47%±3.95%), P<0.001］. All the NK cells were separated into KIR+CD57－, KIR+CD57+, KIR－CD57+, KIR－CD57－ cells based on the expressions of KIR and CD57. The proportions of KIR－CD57+ NK cells (43.03%±5.70%) and KIR－CD57－NK cells (32.45%±5.50%) among NK cells were comparable （P=0.189）, and were higher than those of KIR+CD57+ NK cells (17.67%±3.39%) and KIR+CD57－ NK cells (6.69%±0.95%). Further functional experiments demonstrated that the cytotoxic function and IFN-γ cytokine secretion of CD57+ NK cells and KIR+ NK cells were comparable, which were significantly lower than those of CD56^bri NK cells (P=0.046 and 0.035, respectively), but were equal to those of CD56^dim NK cells. The cytotoxic function and the IFN-γ secretion of KIR－CD57－ NK cells (46.22%± 9.24% and 23.41%±5.82%) were significantly higher than those of the other NK subsets including KIR+CD57－ NK cells，KIR- CD57+ NK cells and KIR+CD57+ NK cells, which were similar to those of CD56^bri NK cells. The cytotoxic function and IFN-γ secretion of KIR+CD57- NK cells were lower than those of KIR－CD57－ NK cells, but were higher than those of CD57+ NK cells, whether KIR positive or negative. The cytotoxic function and IFNγ secretion were similar between KIR+CD57+ and KIR－CD57+ cells. Conclusion: The expressions of KIR and CD57 are correlated with the function of NK cells. Therefore, CD57+ cells might be the end stage of NK cells, KIR－CD57－ NK cells might be the early stage of NK cells, however, KIR+CD57－ showed to be the intermediate stage of the NK cells.

Objective：To explore the levels of TRAP1 and its roles in patients with ovarian tumor, and investigate the correlation between the expressions of TRAP1 in ovarian tumor tissues and related clinicopathological characteristics. Methods: 38 health women, 50 cases of benign ovarian tumors and 114 cases of epithelial ovarian cancers were examined by Real -time RT-PCR and immunohistochemical staining. Results: The immunohistochemical analysis demonstrated that TRAP1 protein was mainly located in the cytoplasm, the protein and mRNA expression of TRAP1 in ovarian cancer were significantly increased compared with those of normal control and benign tumor (P<0.05). The protein and mRNA expression of TRAP1 was related to histological grade and pathologic types (P<0.05), but not age, clinical stages, lymphnode metastasis or omental metastasis, and the amount of ascites (P>0.05). Conclusion: The high expression of TRAP1 may play potential role in epithelial ovarian cancer occurrence and progress.

Objective：To describe the characteristics of acute pancreatitis during pregnancy and postpartum. Methods: From 1994 to 2012, 18 cases of gravida and postpartum women complicated with acute pancreatitis were treated at Peking University Third Hospital and retrospective analysis was performed. Results: The admission rate due to acute pancreatitis was 41.24 per 100 000 admission. The median age was 32.0 (28.0, 34.7) years, with the onset of acute pancreatitis on 35.0 (23.5, 37.0) weeks’ gestation. Of all the cases, 13 (72.2%) were interstitial edematous acute pancreatitis, and 5 (27.8%) were necrotizing. Nine (50.0%) were caused by hyperlipidemia, of which 7 (38.9%) were caused by gallstones, and 2 (1.1%) were idiopathic. Stratified by severity, 6 (33.3%) were mild, 7 (38.9%) were moderately severe and 5 (27.8%) were severe, of which 8 were transferred to Intensive Care Unit. Compared with non-hyperlipidemic acute pancreatitis, cases caused by hyperlipidemia were more severe, however, the prognoses of mothers and infants were good. Conclusion: The incidence of acute pancreatitis during pregnancy and postpartum was similar to that of the regular population, and mostly caused by gallstones and hyperlipidemia. Although acute hyperlipidemic pancreatitis is more severe, the morbidity and mortality of maternal and perinatal could be decreased by aggressive therapy.

Objective：To summarize the etiology and clinical characteristics of children with myopathic elevated creatine kinase (CK) levels. The degrees of elevated CK as well as lactic dehydrogenase (LDH) and aspartate aminotransferase (AST) levels in different myopathy were analyzed. Methods: The clinical data of 235 cases characterized as myopathic hyper-CK-emia from January 2004 to December 2011 were collected and analyzed. A retrospective analysis of LDH and AST levels according to CK in part of the patients were reviewed. Results: Of the 235 cases, 180 were male and 55 female. According to the age at which hyper-CK-emia was diagnosed, 64 cases were under 6 months, 90 between 6 months and 3 years, 50 between 3 and 6 years and 31 between 6 and 14 years. Their CK levels significantly increased in 162 cases, moderately increased in 31 cases, and slightly increased in 42 cases. The age at which hyper-CK-emia was diagnosed and the CK level had no correlation with muscle weakness and the severity. As to CK levels: Duchenne muscular dystrophy (DMD)> inflammatory myopathies>congenital muscular dystrophy (CMD)> metabolic myopathies. LDH and AST levels: DMD> inflammatory myopathies > metabolic myopathies>CMD. Conclusion: Unlike adults, the etiology of myopathic hyper-CK-emia in children is complicated and diverse. The onset type, the degree and duration of hyper-CK-emia are helpful to make the diagnosis. CK increases most significantly in DMD, then in inflammatory myopathies, CMD, and metabolic myopathies. Diagnostic flowchart of myogenic hyper-CK-emia should follow a certain process, and the indications of biochemical tests, metabolic screening, electrophysiological examination, muscle biopsy and genetic testing should be made. Finally, different treatments should be designed according to the etiology.

Objective： To explore the efficacy of surgical treatment and the prognosis factors of spinal metastases secondary to lung cancer. Methods: From April 2005 to April 2012, 35 patients diagnosed as spinal metastases secondary to lung cancer were reviewed retrospectively. All the patients were divided into surgical group and conservative group. Severity of pain, neurological status and quality of life preoperatively and postoperatively were compared; and the relevance between their survival time and radiotherapy, medical therapy (chemotherapy and/or targeted therapy), surgical treatment, quality of life, and neurological status were evaluated. Results: Of all the patients, 28 (80%, 28/35) had been followed up. The surgical group contained 22 cases and the conservative group 6. The severity of pain and quality of life improved significantly in the surgical group. The median of visual analog scale for pain reduced from 7 points to 3 points (z=4.143, P<0.05); the median of Karnorfsky performance score increased from 50 points to 60 points (z=3.825, P<0.05). For the 13 patients in the surgical group who had neurological deterioration, the improvement of Frankel grade was statistically different (z=2.530, P<0.05). The survival analysis indicated that medical therapy had significant association with longer survival (P=0.001). However, surgery, radiotherapy, neurological status and quality of life had no direct relations with survival time. Conclusion: Surgical treatment for spinal metastases secondary to lung cancer can effectively relieve the pain, improve the quality of life and neurological status. The survival time is largely influenced by medical therapy.

Objective：To evaluate the safety and efficacy of albumin-bound paclitaxel in patients with advanced gastric cancer (AGC).Methods: The patients with histopathologic or cytopathologic diagnosed advanced gastric cancer (AGC), Karnofsky performance status≥60, and life expectancy＞12 weeks, and with adequate organ functions of the bone marrow, liver, kidney and heart were recuited in our study. Albuminbound paclitaxel was administered alone or combined with capecitabine, TS1, trastuzumab or cetuxizumb. The total doses of albumin-bound paclitaxel were 200-400 mg （130-260 mg/m2）, divided on days 1, 8 or days 1,8, and 15, given intravenously during 30 minutes of a 21-day cycle. Tumor response was evaluated according to the Response Evaluation Criteria in Solid Tumors (RECIST) 1.0. The adverse events (AE) were graded according to National Cancer Institute-Common Toxicity Criteria (NCI-CTC) 3.0 version. Results: From July 2009 to Octobor 2012, the total of 25 patients were treated and completed 65 cycles of chemotherapy (median: 2 cycles, and range: 0.5-7). The median age was 57 years (range: 38-79). The majority of the patients were with nongastroesophageal junction cancers and had metastasic disease with lymph nodes and peritoneum. Eleven patients were chemotherapy naive and the others had accepted previous systemic therapy for advanced disease. 16 patients were evaluable for clinical response. No complete response was observed and partial response （PR） was achieved in 5 patients. Five patients had stable disease and 6 patients progressed. Among the chemotherapy naive patients, 8 patients were evaluable for response, 3 patients had partial response (37.5%) and 1 patient had stable disease (tumor shrink). The clinical response rate was 50%. Time to treatment failure (TTF）was 3.7 months（95% CI 2.32-5.08） and time to death (TTD）was 7.9 months （95% CI 5.17-10.63）. No statistical differences in TTF and TTD were observed between the untreated and the retreated patients or the monotherapy and the combination therapy groups. All the patients were suitable for safety assessment. Most toxicities were mild with grades 1/2. Hematologic AEs were more common with leucopenia and neutropenia. Meanwhile, nausea/vomiting, fatigue, peripheral neuropathy were the most common non hematologic AEs. No allergic reaction or treatment-related deaths were recorded.Conclusion:AGC patients could benefit from albumin-bound paclitaxel with lower dose level than breast cancer patients. Additional phase Ⅰ/Ⅱ studies of albumin-bound paclitaxel in gastric cancer are warranted.

Objective：To understand the clinical profiles of coexisting rheumatoid arthritis (RA) and ankylosing spondylitis (AS). Methods: Coexisting RA and AS was discussed with 3 cases, 108 similar cases were found in the literature and reviewed here. Results: Coexisting RA and AS was rarely reported. The patients might have family histories of its related diseases, and initially present with diverse symptoms mainly in their youth. All the patients displayed severe symmetrical axial and peripheral arthritis. Joint destruction observed by imaging and the loss of functions were obvious. The prevalence of autoantibodies and HLA alleles was low. Most of the patients hardly demonstrated a good response to ordinary therapies. Conclusion: Patients with coexisting RA and AS present with various symptoms initially and have considerable joint dysfunction as well as unfavorable outcomes. They should receive aggressive therapeutic strategies.

Objective：To investigate whether plasma levels of low density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol (HDL-C) are associated with coronary flow reserve (CFR) in patients with type 2 diabetes mellitus (DM). Methods: Between October 2007 and March 2012，we continuously enrolled 200 participants registered to Department of Cardiology, Peking University Third Hospital, who were divided into 2 groups: DM group (n=95) and control group (n=105). Quantification of CFR was administrated after rest and after adenosine by noninvasive Doppler echocardiography in all the subjects. The CFR, which was performed in the distal part of left descending artery, was used as an indicator of coronary endothelial dysfunction. Results: The plasma levels of LDL-C were significantly higher in the patients with DM than in the controls ［(3.05±0.73) mmo/L vs. (2.74±0.72) mmo/L, P=0.003)］, while the plasma levels of HDL-C were significantly lower in the patients with DM than in the controls ［(1.08±0.24) mmo/L vs. (1.17±0.29) mmo/L, P=0.044］. Furthermore, a lower CFR value was seen in the patients with DM than in the controls ［(2.74±0.63) vs. (3.20±0.69), P<0.001］. The plasma levels of LDL-C were negatively correlated with the CFR values in all the subjects (r=-0.17, P=0.015) and in the DM group (r=-0.23, P=0.021). The LDL-C remained independently correlated with the CFR in the DM group (P=0.036). However，no significantly correlation was found between HDL-C and CFR in the DM group or in all the subjects. Conclusion: LDL-C is independently associated with CFR in patients with diabetic mellitus.

Objective：To assess the effectiveness and complications of rigid endoscopy (RE) and flexible endoscopy (FE) for the extraction of esophageal foreign bodies (FBs) in adults. Methods: A retrospective analysis was conducted on the medical records of 171 adult patients with the upper esophageal FB impaction treated at Peking University Third Hospital, Beijing, China, between January 2008 and December 2012. Results: In the study, 126 patients with the upper esophageal foreign body impaction were treated with RE, while 45 patients received FE. (1)The size of FBs in FE group was the same as RE group （P=0.495, P=0.125）. (2)The period impacted in the esophagus of RE group (25.8±28.6) h was longer than that of FE group (13.9±14.5) h（P=0.009）. (3)71.4% of the patients in RE and 88.9% in FE group went to hospital for treatment within 24 hours from being impacted, while 15.1% in RE group and 8.9% in FE group were between 24 and 48 hours.13.5% in RE and 2.2% in FE group went to hospital beyond 48 hours.(4)The proportion of FBs puncturing into one or two esophageal walls in RE group (67.5%) was higher than that in FE group (35.6%).(5) The positive rates with the upper gastrointestinal barium contrast and chest X-ray or abdominal plain film were 98.3%,23.6% and 100%,14.3% for diagnosing esophageal FBs in RE and FE groups.(6)The successful rate, complication rate and perforation rate were 100%，38.1% and 6.3%and 95.6%，48.9%，and 2.2% in RE and FE groups, respectively with no statistical difference （P>0.05）. Conclusion: Both RE and FE were effective in the extraction of upper esophageal FBs with no difference in the complication and perforation rates. But FE was cheaper and no need for general anesthesia.

Objective：To introduce the technological modification of stents placement with combined naked self-expanding stent and stent-graft for the construction of portosystemic shunt during transjugular intrahepatic portosystemic shunt (TIPS). Methods: In the study, 17 patients who suffered from upper digestive tract hemorrhage due to portal hypertension post liver cirrhosis underwent modified TIPS. The shunts were constructed with stepwise placement of naked self-expanding stent and a stent-graft other than stent-graft only for the purpose of precisely covering the parenchymal segment of the shunt and the active control of portosystemic gradient (PSG). The feasibility, safety, and clinical application results of the new technique were analyzed. Results: Technically, the success rate of operation was 100%. The mean PSG before and after TIPS was (28.2±7.6) mmHg, (12.1±3.5) mmHg, respectively (1 mmHg=0.133 kPa, P<0.001). One patient died 6 days after operation. The median follow-up period was 181 days (ranging from 32 days to 563 days) for all the other 16 cases, during which period 3 patients died because of encephalopathy, liver failure and septicemia, respectively, and 2 cases of encephalopathy occurred and were relieved with medical treatment. The shunts patency rate was 100% and no chance of digestive re-bleeding occurred. The mean Child-Pugh score before TIPS and at the end of the follow-up was (7.8±2.0) points and (7.5±1.7) points, respectively (P=0.584). Conclusion: The technological modification of TIPS with combined naked self-expanding stent and stent-graft for the precise covering of the parenchymal segment of the shunts was relatively simple to apply, and was helpful for the adjustment of PSG. The preliminary clinical application indicated that it had satisfying results in the matter of shunts patency, incidence of encephalopathy, and the relapse of digestive bleeding during the short-term follow up.

Objective：To observe the preventive effect of two fractionations for postoperative radiotherapy of keloid and discuss the optimal way for postoperative radiotherapy. Methods: We enrolled 107 consecutive keloid patients with 139 lesions from August 2011 to October 2012 in Department of Radiation Oncology of Peking University First Hospital. There were 114 lesions (the largest lesion part will be accounted if there are several lesions in the single body area) into the curative effect of the statistics. All the patients received irradiation after operation within 24 hours. The patients were divided into two groups: 5 Gy/f for continuous 4 days (5 Gy group); 4 Gy/f for continuous 5 days (4 Gy group). The lesions were treated by 6 MeV-E by Varian 21EX medical linear accelerator made in America. The irradiation field was surgical incision plus 1 cm in radial directions. One centimeter bolus was put on the skin to attain the therapeutical dose of skin surface. The total dose for each lesion was 20 Gy. The treatment effect of keloid was classified into cure, excellence and recurrence, referring to Darzi’s standard. Effectivity means the sum of cure and excellence. SPSS 14.0 was used to statistically analyze the data. Results: The total effective rate for 5 Gy group was 90.7% (49/54) and 66.7% (40/60) for 4 Gy group (P=0.001). The lesions were divided into three regions according to the tension of the skin: ear/face/neck region, chest wall/shoulder/back region and other regions. The treatment effects of 5 Gy group and 4 Gy group were 94.1% (16/17) vs. 85.0% (17/20) for ear/face/neck region, 89.7% (26/29) vs. 60.0% (18/30) for chest wall/shoulder/back region and 87.5% (7/8) vs. 50.0% (5/10) for other regions. Significant difference was found in chest wall/shoulder/back region (P=0.009). No obvious toxicities occurred in any group. Conclusion: Postoperative radiation therapy within 24 hours of 5 Gy/f for continuous 4 days and 4 Gy/f for continuous 5 days is effective, especially in 5 Gy/f group. It is suggested that hypofractionated radiation therapy is more effective for keloid patients, and it is also economical and convenient for patients and worth further discussing.

Objective： To observe the effect of delayed administration of etanercept on the motor function, the expression of apoptosis-related genes and the pathological alterations of spinal cord in vivo in experimental murine model of spinal cord injury (SCI). Methods: Seventy-two male adult SD rats were randomly divided into 6 groups, which were subjected to SCI induced by the application of vascular clips (force of 70 g) to the dura. Experimental groups (E1, E2, and E3 group) were given administration of etanercept immediately, 1 h, and 8 h after SCI. The control groups (C1, C2, and C3 group) were given administration of saline at the same time as experimental groups. Six rats of each group were killed 24 h  after SCI in order to collect the samples for testing the expression of Bax and Bcl-2 by Western blot. The rest were killed 14 d after SCI for observing the pathological alteration using light microscopy. The recovery of motor function was graded using the modified murine Basso, Beattle, and Bresnahan (BBB). Results: (1) The results of the expressions of Bax and Bcl-2 by Western blot: the gray value of the expression of Bax of E1 group was 165.423±2.946, of E2 group 135.391±3.045, of E3 group 108.543± 6.999, and of the control group 69.054±0.774, and the gray value of the expression of Bcl-2 of E1 group was 58.854±3.592, of E2 group 84.315±2.138, of E3 group 125.091±2.699, and of the control group 156.304±2.490. (2) The results of BBB score: etanercept given immediately or 1 h after SCI could improve the recovery of the rats. There were significant differences in BBB score 14 d after SCI between E1 group (13.000±1.095) and C1 group (7.167±0.753), E2 group (9.833±1.472) and C2 group (7.000±0.632)  while there were no significant difference between E3 group (7.333±0.516) and C3 group (6.833±0.753). (3) The result of histological alteration: histological alterations, such as necrosis, infiltration of lymphocytes and fibroblast and loss of nerve cells, were found attenuated in  E1 and E2 groups, compared with C1 and C2 groups. There was no obvious difference between E3 and C3 groups.  Conclusion: Administration of etanercept may inhibit the apoptosis after SCI, but this kind of effect may be too weak to improve the BBB score and histological alterations obviously when administration of etanercept is delayed 8 h after SCI. The clinical value of etanercept to SCI needs to be further validated.