Objective To investigate the effect of preoperative pravastatin preconditioning on myocardial ischemia-repedusion(I／R)injury in patients undergoing cardiac valve replacement with cardiopulmonary bypass (CPB).Methods Sixty ASA Ⅱ orⅢpatients of both sexes aged 18-64 yr undergoing cardiac valve replacement under CPB were randomly divided into 4 groups(n=15 each)：control group(group C)and 3 pravastatin groups receiving oral pravastatin 10，20 and 40 mg respectively every night for 7 days before operation(group P1-3).The number of patients receiving dopamine(≥5 μg·kg-1·min-1)and adrenaline was recorded from the termination of CPB to the end of operation，from the end of operation to 12 h after operation，during 12-24 h after operation and during 24-48 h after operation.Venous blood samples were taken from central venous line for measurement of plasme cTnI and CK-MB concentrations at 7 days before operation，before induction of anesthesia，at opening of the aorta and at 2，24 and 48 h after opening of aorta.Results The number of patients receiving dopamine and adrenaline was significantly less in group P3 than in group C(P<0.05).Plasma CK-MB and cTnI concentrations were significantly lower in group P3 than in group C(P<0.05).Conclusion Preconditioning with oral pravastatin(40mg／d for 7 consecutive days)can protect myocardium against I／R injury in patients undergoing cardiac valve replacement with CPB.

Objective To study the MTHFR gene (677 gene loci and 1298 gene loci) mutations in Chinese patients with keloid. Methods The tissue DNA was extracted from 20 samples of keloids. and peripheral blood samples from the same patients were employed as the control. Polymerase chain reaction(PCR) was used to amplify the Mthfr 677 gene loci and Mthfr 1298 gene loci from the keloid tissue DNA and peripheral blood DNA. and the PCR products were sequenced directly and then compared with the GenBank data. Results Mutations were detected in 17 out of 20 keloids on Mthfr 677 gene loci, the mutation incidence was 85.0 %. Mutations were detected in 13 out of 20 keloids on Mthfr 1298 gene loci, and the mutation incidence was 65.0 %. The mutation involved point mutation, deletion and insetion as well as multisite and multitype. No MTHFR gene mutation was detected in all peripheral blood samples . Conclusion There is a strong correlation between the MTHFR gene (677 gene loci and 1298 gene loci) mutation and keloid.

Objective To establish the examination criteria for the prosthodontic clinical practice using Delphi method,to improve the evaluation level of clinical practice of dental students.Method 15 clinical experts in the department of prosthodontics,Peking University School of Stomatology were selected in this study.The evaluation indicators system of prosthodontic clinical practice was established by two rounds of investigations by Delphi method.Initiative ratio and authority coefficient (Cr) of the experts were used to evaluate the reliability of the new examination criteria.Next,the eight-year program students in class of 2007 (38 students) and 2008 (34 students) were examined by old and new examination criteria respectively and the feedback of the students were collected by the method of questionnaire.SPSS 16.0 was used for data processing.Results In this study,the initiative and the authority of the experts was very high,and the initiative ratio and authority coefficient were 100％ and 0.860 respectively.A new examination criterion of prosthodontic clinical practice was established,including 3 first-level indicators,9 second-level indicators and 19 third-level indicators.Questionnaire analysis revealed that only 12％ (n=4) and 9％ (n=3)of the students in class of 2008 considered the new examination criteria was not comprehensive enough or objective enough,which was obviously less than the students in class of 2007 [45％ (n=17) and 36％ (n=14)].Conclusion A new examination criterion of prosthodontic clinical practice was successfully established by Delphi method.The new examination criterion is more comprehensive and objective than the old one and can promote the educational quality of clinical practice of dental students.The method of this study also provides reference for the educational reform of clinical practice in other fields.

Objective:To explore a new method of whole-process digital esthetic prosthodontic rehabilitation combined with periodontic surgery for complicated anterior teeth esthetic defects accompanied by soft tissue morphology,to provide an alternative choice for solving this problem under the guidance of three-dimensional (3 D) printing digital dental model and surgical guide,thus completing periodontic surgery and digital esthetic rehabilitation of anterior teeth.Methods:In this study,12 patients with complicated esthetic problems accompanied by soft tissue morphology in their anterior teeth were included.The dentition and facial images were obtained by intra-oral scanning and three-dimensional (3D) facial scanning and then calibrated.Two esthetic designs and prosthodontic outcome predictions were created by computer aided design/computer aided manufacturing (CAD/CAM) software combined with digital photography,including consideration of white esthetics and comprehensive consideration of pink-white esthetics.The predictive design of prostheses and the facial appearances of the two designs were evaluated by the patients.If the patients chose the design of comprehensive consideration of pink-white esthetics,they would choose whether they would receive periodontic surgery before esthetic rehabilitation.The dentition design cast of those who chose periodontic surgery would be 3D printed for the guide of periodontic surgery accordingly.Results:In light of the two digital designs based on intra-oral scanning,facing scanning and digital photography,the satisfaction rate of the patients was significantly higher for the comprehensive consideration of pink-white esthetic design (P ＜ 0.05) and more patients tended to choose priodontic surgery before esthetic rehabilitation.The 3 D printed digital dental model and surgical guide provided significant instructions for periodontic surgery,and achieved success transfer from digital design to clinical application.The prostheses were fabricated by CAD/CAM,thus realizing the whole-process digital esthetic rehabilitation.Conclusion:The new method for esthetic rehabilitation of complicated anterior teeth esthetic defects accompanied by soft tissue morphology,including patient-involved digital esthetic analysis,design,esthetic outcome prediction,3D printing surgical guide for periodontic surgery and digital fabrication is a practical technology.This method is useful for improvement of clinical communication efficiency between doctor-patient,doctor-technician and doctors from different departments,and is conducive to multidisciplinary treatment of this complicated anterior teeth esthetic problem.

Objective:To explore a method of constructing universal 3-dimensional (3D)colorized digital dental model which can be displayed and edited in common 3 D software (such as Geomagic se-ries),in order to improve the visual effect of digital dental model in 3D software.Methods:The mor-phological data of teeth and gingivae were obtained by intra-oral scanning system (3Shape TRIOS),con-structing 3D digital dental models.The 3D digital dental models were exported as STL files.Meanwhile, referring to the accredited photography guide of American Academy of Cosmetic Dentistry (AACD),five selected digital photographs of patients’teeth and gingivae were taken by digital single lens reflex camera (DSLR) with the same exposure parameters (except occlusal views ) to capture the color data.In Geomagic Studio 201 3,after STL file of 3D digital dental model being imported,digital photographs were projected on 3D digital dental model with corresponding position and angle.The junctions of different photos were carefully trimmed to get continuous and natural color transitions.Then the 3 D colorized digital dental model was constructed,which was exported as OBJ file or WRP file which was a special file for software of Geomagic series.For the purpose of evaluating the visual effect of the 3 D colorized digital model,a rating scale on color simulation effect in views of patients’evaluation was used.Sixteen patients were recruited and their scores on colored and non-colored digital dental models were recorded.The data were analyzed using McNemar-Bowker test in SPSS 20.Results:Universal 3D colorized digital dental model with better color simulation was constructed based on intra-oral scanning and digital photography. For clinical application,the 3D colorized digital dental models,combined with 3D face images,were in-troduced into 3D smile design of aesthetic rehabilitation,which could improve the patients’cognition for the esthetic digital design and virtual prosthetic effect.Conclusion:Universal 3 D colorized digital dental model with better color simulation can be constructed assisted by 3 D dental scanning system and digital photography.In clinical practice,the communication between dentist and patients could be improved as-sisted by the better visual perception since the colorized 3 D digital dental models with better color simula-tion effect.

Objective To observe vasculogenic mimicry formation difference in human hepatocellular carcinoma cell lines MHCC97-H/L with different metastatic potentials under three-dimensional culture condition,and to study extracellular matrix and adhesion molecules-related mechanism of vasculogenic mimicry.Methods Three-dimensional cell culture system of MHCC97-H/L was established to observe tubelike structures by inverted microscope.Human umbilical vein endothelial cell(HUVEC),human hepatocellular carcinoma cell line Hep3B with non-metastatic potentials and normal human hepatic cell line HL-7702 were taken as control.Gene expression profiles of MHCC97-H and MHCC97-L were detected by Oligo extracellular matrix and adhesion molecules microarray analysis.Two differentially expressed genes were verified with semi-quantitative reverse transcriptionpolymerase chain reaction(RT-PCR)and Western blot.All data were analyzed using two sample t test.Results After a 24-hour three-dimensional culture,the length of tubelike structures was(474 ± 16)mm/cm2 in MHCC97-H,which were significantly longer than(320 ±41)mm/cm2 in MHCC97-L(t =6.119,P ＜0.05).Hep3B and HL-7702 could not form tubelike structures.Compared with MHCC97-L,the expression of 7 genes were up-regulated and the expression of 3 genes were down-regulated among a total of 113 angiogenesis genes in MHCC97-H.Two of the genes with differential expressions including tenascin C and extracellular matrix protein 1 were further validated by RT-PCR and Western blot.Conclusion MHCC97-H has stronger ability to form vasculogenic mimicry than MHCC97-L,and this perhaps correlates with the differential expression of certain extracellular matrix and adhesion molecules-related genes in MHCC97-H.

Objective To investigate protective effects and mechanisms of lipoxinA4(LXA4)on human umbilical vein endothelial cells(HUVEC)under hypoxia in vitro.Methods The HUVEC culture were divided into groups as followed:added M199 cudture medium as normal contml groups,added CoCl2 to mimic hypoxia in vitro as hypoxia group and added different concentrations of LXA4(1,10,100 nmol/L)were added to the induced hypoxiai HUVEC as agents intervention group.Morphological changes of HUVEC were observed by using inverted phase contrast mieroscope.The influence of LXA4 on cell survival was investigated by methyl thiazolyl tetrazolium(MTT) assaying method after the treatment with different concentrations of LXA4 and 100 nmol/L lipoxinA4 according to different time(4,8,12 and 24 hours).The expression of von-willebrand factor (vWF) was detected by immunocytoehemistry method. The changes of cytosolic Ca2+ were measured by laser scanning confocal microscope. Results ( 1 ) Morphological changes:the cells under hypoxia lost its normal shapes and showed necrosis, while the cells cocuhured with 100 nmol/L LXA4 were normal appropriately. (2)Survival rate: the survival rates of HUVEC under hypoxia was (40. 1±3.9) % and increased to ( 52. 9 ± 1.4) %, (64. 1 ± 3. 3 ) %, ( 76. 6 ± 1.6) % respectively when added with LXA4 with concentration of 1,10, 100 nmol/L into culture medium. There was significant different survival rate when compared with that of hypoxia group. (3) The level of vWF: The expression of vWF was decreased with the increasing concentrations of LXA4 added into culture medium, the gray values were 203.9 ±0. 7 in 1 nmol/L,204.6 ±0. 9 in 10 nmoL/L,191.8 ±0. 5 in 100 nmol/L respectively, which reached statistical difference in comparison with that of hypoxia groups (P<0. 05). (4) Confocai analysis:the intracellular free Ca2+ concentrations of HUVEC were intensified with LXA4 treatment. Conclusions LXA4 plays an important role in keeping the normal shape of HUVEC under hypoxia, can enhance survival of hypoxial HUVEC and decrease the level of vWF in cytoplasm. The protective mechanism might be via decreasing mitochondria Ca2+ overload and increasing cytoplasm Ca3+ by nucleus Ca2+ transference.

Objective To investigate the value of intravoxel incoherent motion MR imaging (IVIM-MRI)on monitoring impairment of renal function in hydronephrosis.Methods Left hydronephrosis model of Healthy New-Zealand rabbits made by ureteral incomplete obstruction were scanned by IVIM-MRI at 4, 8, 12, and 16 weeks.The change of IVIM-MRI quantitative parameters (ADC values, D values, D* values, and f values) in left hydronephrosis kidney were observed.The correlation between these parameters and glomerular filtration rate (GFR) were evaluated.Results ADC values, D values, D* values and f values at cortex and medulla in left hydronephrosis model of rabbits decreased gradually in the progression of renal damage after 4, 8, 12, and 16 weeks.For D value, f value and ADC values, there was statistical significant difference among the group of 12 weeks, the group of 16 weeks, the control group, and the group of 4 weeks;statistical significant difference was also observed between the group of 8 weeks and the group of 16 weeks by LSD contrast.ADC values, D values, D* values, and f values were positively correlated to GFR at 4, 8, 12, and 16 weeks for left hydronephrosis model of rabbits.Conclusion IVIM-MRI could monitor impairment of renal function in hydronephrosis dynamically.

Objective To assess the cardiovascular events after percutaneous transluminal coronary intervention (PCI) and the influence of fluvastatin on inflammation factors and prognosis of PCI patients.Methods One hundred and eighty-seven patients whose coronary stenosis ≥ 70% diagnosed through coronarography and underwent PCI from Jun.2005 to Feb.2008 were recruited in the current study.These patients were divided into two groups,the control group (n =91) was treated regularly and the treat group (n =96) was treated with additionally fluvastatin(40 mg/d).Fasting venous blood was obtained before and after medicine treatment,12,24 hours and two weeks after PCI.IL-18,IL-6 and TNF-α were measured through ELISA.Results Before medicine treatment,there were no difference of IL-18 ,IL-6 and TNF-α between the two groups( P ＞ 0.05 ).After medicine treatment,IL-18,TNF-α and IL-6 decreased significantly compared to those before treatment in both groups ( P ＜ 0.05 ),and these measurements decreased more in the treatment group ( P ＜ 0.01 ).At the 12th hours after PCI,IL-18,TNF-αand IL-6 in the control group increased to (423.5 ± 298.7 ),( 316.1 ± 72.6 ) and (42.3 ± 10.1 ) ng/L,respectively,and arrived the peak at the 24th hour,which were significantly higher than those before medicine treatment( P ＜ 0.01 ).In the treatment group,these measurements at the 12th and 24th hour after PCI were slightly higher than those before medicine treatment without significant difference ( P ＞ 0.05 ).After 12 hours ofPCI,IL- 18,TNF -αand IL-6were (276.5 ± 189.4 ),( 175.3 ± 51.9) and ( 10.1 ± 8.1 ) ng/L,which were significantly lower than those in the control group(P ＜ 0.01 ).Two weeks after PCI,IL-18,TNF-α and IL-6 in the treatment group were (137.0 ±34.2),(35.1 ± 21.6) and ( 8.7 ± 3.2 ) ng/L,which were significantly lower than before medicine treatment ( P ＜0.01 ).Conclusions PCI may aggravate the inflammation response of coronary artery.Statins may alleviate the inflammation response.IL-18,TNF-α and IL-6 are sensitive indices of early inflammation response after PCI,their changes might have prediction value for adverse cardiovascular events.Therefore these indices might be used as a target in the statins treatment in the primary prevention,as well as the evaluation of the effectiveness of PCI,statins and joint PCI and statins.

ObjectiveTo compare X-ray,spiral CT and low does digital subtr,action angiongraphy technology of three dimensional reconstruction in 30 cases of the applications in the joint fractures,to study the application value of the digital subtraction angiography three- dimensional reconstruction in joint fracture.MethodsA retrospective analysis was made on 30 cases with joint fracture in Guangdong Provincial Guangzhou Development District Hospital,who were confirmed by the X-ray and spiral CT three-dimensional reconstruction and digital subtraction angiography three-dimensional reconstruction and the demonstrations three-dimensional reconstruction,spiral CT three-dimensional reconstruction and X-ray were compared.ResultsAll 30 cases fractures showed clear line,line of walk line,of the number of fracture,source and separation shift condition.Digital subtraction angiography could be clearly shows 30 cases in spiral CT could clearly show in 20 cases,10 cases not clearly show in,while X-ray clearly show in 10 cases,not show in 20 cases.Spiral CT showed clearly joint capsule and soft tissue.The SPSS 11.0 statistical soft package was used.Spearman correlation analysis,the single factor analysis of variance and the independent t test and the chi-square test were employed for data analysis,P ＜ 0.05 was considered statistical significance.Conclusions Digital subtraction angiography three-dimensional reconstruction can more clearly display fracture line,fracture pieces,walk line,source and separation shift condition compared with spiral CT and Xray essaminations,which is helpful for treatment options and prognosis estimation.