Objective To investigate the effects of Stichopus variegatus mucopolysaccharide on plasma nitric oxide (NO) and serum endothelin(ET) after angioplasty in rabbits. Methods 50 New Zealand rabbits were randomly divided into four groups: Stichopus group, simvastatin group, model group and normal group. Endothelium of iliac arteries in Stichopus group, simvastatin group and model group were denuded by balloon catheter and the rabbits were fed with 2%cholesterol, 3%lard and 3%yolk mixed forage for six weeks, and then, atherosclerotic stenosis was showed by iliac angiography.When transluminal balloon angioplasty was done, from then on the feeds was changed from high cholesterol to ordinary forage. Stichopus (0.5g?kg -1?d -1) and simvastatin (0.5mg?kg -1?d -1) were given by gastric canal. While NaCl solution (0.9%) was given in model group. All rabbits were fed in separate cages and free drinking. After four weeks since transluminal balloon angioplasty, blood was collected from carotid artery to measure the changes of concentrations of endothelin(ET) and nitric oxide(NO). Examination of pathology by optical and electron microscope were done at same time. Results After four weeks since transluminal angioplasty, the concentration of plasm ET in model group increased significantly compared with the normal group(114.86?24.89 ng?L -1 vs 75.62?9.68 ng?L -1) and serum NO decreased significantly(37.50? 12.79?mol?L -1 vs 106.37?18.01 ?mol?L -1).The concentration of plasm ET in model group was higher than that in the simvastatin groups and Stichopus groups(114.86?24.89 ng?L -1 , 81.08?14.71 ng?L -1 and 83.34?11.41 ng?L -1 ,respectively),and the concentration of serum NO decreased obviously(95.63?8.62 ?mol?L -1,98.80?9.06 ?mol?L -1 and 37.50?12.79 ?mol?L -1,respectively). Conclusion After iliac arterial TA the concentrations of plasm ET were increased and the serum NO were decreased, the endothelial function fell into disorder. The Stichopus variegatus mucopolysaccharide had the effects of improving the endothelial function after angioplasty in rabbits by adjustment of plasm ET and serum NO.

The paper analyzed on the status quo of postgraduate and undergraduate education of orthodontics in China and seek solutions for improving conjunction between these two different stages by presenting measures in seven respects including grading undergraduate education curricu-lum,launching students seminar,developing students' scientific research activities,adjusting evalua-tion system,emphazing on bilingual teaching,distinguishing types of postgraduates and seting up the communication channel so as to find a proper way for orthodontic education in China.

Objective To study the mental health conditions of students majored in stomatology and dental technology in internships,and to provide evidences and guidelines for education before and during exercitation.Methods Totally 90 students majored in stomatology and 60 students majored in dental technology in internships were surveyed by the questionnaires of symptom checklist (SCL90)and perceived social support scale (PSSS).Results were analyzed by SPSS 14.0.Measurement data was analyzed using t test comparison between groups,showed as mean ± standard deviation ((x) ± s).Positive screening rate and rate between male and female were analyzed by Mann-Whitney U inspection.The inspection level is α =0.05.Results Scores of somatization,paranoia and anxiety factors among students majored in stomatology were (1.49 ± 0.56),(1.52 ± 0.43),(1.73 ± 0.58),all significantly higher than those of the national norm of youth.Positive rate of mental diseases among students majored in dental technology was 77.59％ and their scores of somatization,constraint,anxiety,psychotic factors were (1.69 ±0.55),(2.07 ±0.5),(1.68 ±0.51) and (1.54 ±0.39),all significantly higher than those of students majored in stomatology.There was no difference in the scores of rest factors between the two groups.Scores of PSSS among students majored in dental technology were significantly lower than those of students majored stomatology.Conclusions Students of different majors all suffer from psychological problems with different degrees.Therefore,education,management and social support before and during exercitation should be emphasized in the prevention of psychological diseases.

Objective To establish the method of isolation,culture and identify biological characterization of mesenchymal stem cells from human umbilical cord (hUCMSCs);and study their multiple differentiation potency.Methods Stem cells from human umbilical cord were cultured by enzyme Wharton jelly method in vitro.The surface markers were identified by flow cytometry.Multi-differentiation capacity was identified by osteogenic and adipogenic differentiation.ALP was detected with Calcium cobalt staining.The mineralized ability in vitro was measured with Alizarin red staining.Theadipocyte differen-tiation ability was measured with oil red-O staining.Results Flow cytometry analysis revealed that CD73 (92.45%),CD90 (95.45%)and CD105 (96.45%)were highly expressed on these cells’surface,while CD34 (1.07%)were negative ex-pressed.Cells were cultured with induced-osteogenic medium after 3 weeks,ALP staining in the cytoplasm of black parti-cles,and a large amount of mineralized nodules within cells was observed after 4 weeks.Cells were cultured with induced-adi-pogenic medium after 2 weeks,the majority of these cells were round,oil red O staining of lipid droplets generated within cells was observed.Conclusion Mesenchymal stem cells from human umbilical cord have the potential of multi-directional differentiation.These cells could be induced to differentiate into adipocytes and osteoblasts,which laid the foundation for clinical stem cell therapy research source of seed cells.

Objective:To evaluate the effect of pinus massoniana bark extract (PMBE) and grape seed extract (GSE) on dentin demineralization caused by acid.Methods:40 root dentin blocks with half of the surface covered were randondy divided into 4 groups (n =10).All samples were subjected to pH cycling for 8 days,and deionized distilled water(DDW),0.1％NaF,12％ PMBE solution and 12％ GSE solution were used as the experimental solutions in the 4 groups.The dentin mineral density(DMD) of the both sides was determined using micro-computed tomography.The D-value of DMD between nn-demineralized and demineralized side (△DMD)was calculated.The samples were observed with field emission scanning electron microscops (FE-SEM).Results:The △DMD of DDW,NaF,PMBE and GSE groups was 198.64 ±59.97,45.94 ±24.21,90.23 ±28.77 and 105.07 ±29.53 respectively.The △DMD between PMBE and GSE groups had no significant difference (P ＞ 0.05),which were both higher than that of NaF group (P ＜ 0.05) and lower than that of DDW group(P ＜ 0.05).The FE-SEM revealed that the dentin tubules in DDW group were completely open,but in NaF group were essentially closed in PMBE group and GSE group were spindle shaped or narrow crack opening.Conclusion:PMBE and GSE had almost the same effect on improving the acid resistance of dentin.

Aiming at the new problems in orthodontics teaching and employment,this study aims to explore a more suitable undergraduate teaching mode of Orthodontics,and reform the teaching of Orthodontics for five-year program students in department of stomatology of Xi'an Medical University.During the teaching of Orthodontics,teachers use the aesthetic principles that students have learned to integrate into the orthodontics teaching,and guide students to analyze,understand and master orthodontic knowledge based on the principles of aesthetics.After the course,students give good feedback on the teaching reform,and their scores of basic knowledge and case analysis of Orthodontics theoretical examination have been improved.This teaching reform is very helpful for students to learn,understand and master the knowledge of orthodontics.It helps to improve classroom teaching effect,improve students' interest in learning,and adapt to the needs of discipline and industry development,so it is worth studying and promoting.

Objective To investigate the effects of local application of insulin like growth factor-1 (IGF-1) absorbable gelatin sponge complex in implant fossa on osseointegration around implant in osteoporosis rats.Methods Female SD rats,aged 4 months,were randomly individed into ovariectomy group (OVX group) and sham-ovariectomy group (sham-ovx group).The rats in OVX group (n=15) were ovariectomized,and the rats in Sham-OVX group (n=10) underwent Sham-ovariectomy.Eight weeks later,5 rats in each group were randomly selected to confirm the osteoporosis model.The ovariectomized rats were randomly divided into osteoporosis group (OP group) and IGF-1 group after the model was successfully established,5 rats in each group.Pure titanium implants were implanted in the distal part of right femoral epiphyseal in all groups.Absorbable gelatin sponge particles containing 10 μg IGF-1 were placed in the planting fossa in the IGF-1 group,and absorbable gelatin sponge particles without IGF-1 were used in OP group and sham-OVX group.The rats were sacrificed,and then the distal part of right and left femoral epiphyses were taken out to make undecalcified and decalcified tissue sections respectively after 8 weeks.Combined bone lamelta width (CBLW) and implant bone contact rate (IBCR) around implant,trabecular width (TW) and trabecular area percentage (TA) around implant and in the cortical bone of left femoral epiphyses were observed by histomorphometric measurement.Results The CBLW,IBCR,TW and TA around implant was(55.43±3.50)μm,(81.79±4.45) ％,(57.73 ±4.29) μtm and (62.21 ±7.42) ％ respectively in sham-OVX group,(60.22±4.70)μm,(83.67 ±6.63)％,(48.08 ±3.63) μtm and (58.20±8.93) ％ respectively in IGF-1 group,and (37.11 ±2.18) μtm,(64.60±5.44)％,(41.19 ±2.93) μm and (42.21±4.34) ％ respectively in OP group.The CBLW,IBCR and TW around implant had no differences between IGF-1 and sham-OVX group (P ＞ 0.05),which were significantly higher than those in OP group(P ＜ 0.05).The TW and TA of cortical bone in left distal femoral epiphyses was (60.85 ±6.64) μtm,(61.24 ±6.98) ％ respectively in shamOVX group,(38.68 ±4.74) μtm,(43.89 ±7.76) ％ respectively IGF-1 group,(40.46±5.38) μtm,(44.63±5.39) ％ respectively in OP group (P ＜ 0.05).The TW and TA of cortical bone in left distal femoral epiphyses had no differences between IGF-1 group and OP group (P ＞ 0.05),which were all significantly lower than those in sham-OVX group (P ＜ 0.05).Conclusions The local application of IGF-1 gelatin sponge complex can increase bone tissue around implant and improve osseointegration in osteoporosis.

Objective To investigate the epidemiology characteristics of crawfish related rhabdomyolysis (RM) in Nanjing, 2016.Methods Outpatient and inpatient electronic medical system of 21 hospitals in Nanjing during 2016 were retrospectively searched, and all the patients diagnosed with RM were selected. The patients with none crayfish-related RM was excluded. The epidemiology characteristics were depicted. The geographic information system (GIS) was used to collect, manage and analyze the spatial data, to visualize it, to analyze the spatial distribution features of the disease, and to explore the cause of disease prediction. GeoDa 1.8 software was used to analyze the global and local spatial auto-correlation.Results A total of 1183 patients with crawfish related RM were initially screened, excluding 59 patients with RM caused by trauma, severe exercise, heat stroke, myositis, poisoning, drugs, and genetic diseases, and 1124 patients were enrolled. The proportion of men was 36.48% (410/1124) with an incidence of 12.54/100 thousands; while of women was 63.52% (714/1124) with an incidence of 21.86/100 thousands. The median age at onset was 34 (28, 43) years. From July to August, the incidence of crawfish related RM was the highest, accounting for 96.53% of the total number of cases. The top four incidence areas were Pukou (41.54/100 thousands), Jianye (25.94/100 thousands), Qixia (25.73/100 thousands), Gulou (25.04/100 thousands), all of which were adjacent to the Yangtze River. Global spatial autocorrelation analysis showed: MoranI = 0.427,Z = 2.646,P = 0.003, suggesting that the crawfish related RM had positive spatial autocorrelation. The results showed that the spatial structure of crawfish related RM existed in Nanjing in 2016. Local spatial autocorrelation analysis showed that the high-high concentration areas were Pukou, Jianye and Liuhe. The incidences of above three areas which were the Nanjing section of the lower reaches of the Yangtze River flowed through the region and surrounding areas were higher than the overall incidence of Nanjing.Conclusion The prevalence of crawfish related RM in Nanjing during 2016 had an obvious region-concentrated character and global spatial autocorrelation with the high prevalent regions mainly concentrated in the urban areas adjacent to the Yangtze River.

OBJECTIVEThis study aims to evaluate the effects of Pinus massoniana needle extract (PMNE) on inhibiting demineralization of root dentin.

METHODSRoot dentin blocks were randomly divided into distilled deionized water (DDW) group, fluoride sodium (NaF) group, and 4%, 8% and 12% PMNE groups according to the experimental solution used in the process of pH cycling in each group. All specimens in each group experienced pH cycling for 8 d. The dentin mineral density (DMD) of the normal dentin and demineralized dentin and their D-value (ΔDMD) were determined using micro computed tomography. The morphology of dentin surface after pH cycling was also observed using a scanning electron microscope.

RESULTSThe ΔDMD values in all PMNE groups and the NaF group were considerably lower than the ΔDMD in the DDW group (P<0.05). The ΔDMD values of the 8% and 12% PMNE groups had no difference (P>0.05), both of which were lower than the ΔDMD in the 4% PMNE group and higher than that in the NaF group (P<0.05). The dentin tubules were partly opened in the PMNE groups. The opening degrees of the dentin tubule in PMNE groups were significantly less and smaller than the opening degree in the DDW group and were larger than that in the NaF group.

CONCLUSIONSPMNE can inhibit the deminera-lization of root dentin and can slow down the reduction in DMD. PMNE has the potential to prevent caries, and 8% PMNE can effectively inhibit dentin demineralization.