【Objective】To improve the adaptation of Plat-Ⅱceramic crown.【Method】The Plat-Ⅱcastable ceramic crowns were made by three methods,namely routine method,die spacer technique,and the model investing method.24 crowns were made by these three methods individually and adhered to the corresponding model die with zinc phosphate to measure the adhesive thickness and compare their adaptation.【Result】The average adhesive thickness at different parts of crown of these three groups were 52 μm、42 μm、30 μm and the margins discrepence were 63 μm、59 μm、42 μm,respectively.There is statistically difference in both the adhesive thickness and the margin discrepence with these three methods (P<0.01).【Conclusion】The crowns made from the die spacer technique and the model investing method could improve the adaptation significantly.

Animals ; Corticosterone ; pharmacology ; Hippocampus ; drug effects ; physiology ; In Vitro Techniques ; Long-Term Potentiation ; drug effects ; physiology ; Male ; Rats ; Rats, Wistar

BACKGROUND:Ideal tissue-engineered urinary tract should have good mechanical properties to bear long-term attack of urine and excretion. Muscular conduit of urinary tract in static culture exerts poor strength. It is reported that mechanical stimuli promote cellular growth and secretion of extracellular matrix. OBJECTIVE:To investigate the feasibility of constructing tissue-engineered muscular conduit of urinary tract in bioreactor. METHODS:Adipose-derived stem cells were harvested by col agen enzyme method. After series culture and expansion in vitro, flow cytometric analysis was carried out to detect the immunophenotypes of adipose-derived stem cells. Then the cel-polyglycolic acid complex was constructed by seeding adipose-derived stem cells on polyglycolic acid fibers. After 1 week of in vitro culture, cel-polyglycolic acid complex was cultured in a bioreactor. The experimental group was subjected to pulsatile stimuli, while the control group was cultured in static state. After 3 weeks of in vitro culture in basic medium, the cel-polyglycolic acid complex was induced in the induced culture medium for 4 weeks, and then engineered tissue was examined both grossly and histological y. RESULTS AND CONCLUSION:Flow cytometry demonstrated that the adipose-derived stem cells expressed CD90 (99.42%), CD44 (98.12%) and CD105 (93.27%), but not CD34 (4.92%) or CD45 (0.38%). In the experimental group, tissue-engineered muscular conduit of urinary tract appeared bright color with a round lumen. Immunohistochemical staining showed that after cel-polyglycolic acid complex was induced for 4 weeks, the cells expressed desmin and α-smooth muscle actin. More col agen was found in the complex. In contrast, the control group appeared pale surface and its lumen col apsed slightly. Less col agen was in the complex. Tissue-engineered muscular conduit of urinary tract with good structure can be constructed in a bioreactor.

BACKGROUND:Neurotrophin-3 is found in the repair of spinal cord injury in the role of the strongest neurotrophic factor.It can effectively promote axonal regeneration through the glial scar tissue in repairing spinal cord injury.OBJECTIVE:To construct recombinant lentiviral vectors for gene delivery of homo sapiens neurotrophin-3(hNT3),and to investigate the expression of hNT3 gene in Schwann cells after transfection.DESIGN,TIME AND SETTING:Observational experiment was performed from June 2007 to March 2008 at the Central Laboratory of Changhai Hospital.MATERIALS:Bilateral sciatic nerves were harvested from 3-day-old Sprague Dawley rats for culture and identification of Schwann cells.Three-plasmid lentivirus systems:pGC-E1-EGFP,pHelper 1.0 and pHelper 2.0 were gained from Shanghai Chemical Technology Co.,Ltd.METHODS:pGC-E1-hNT3-EGFP plasmid was constructed by double restriction enzyme digestion and ligation,and then the plasmid was transformed into E.coli DH5?.Purified pGC-E1-hNT3-EGFP plasmids from the positive clones was confirmed by PCR and sequencing.293T cells were cotransfected with lentiviral vector pGC-E1-hNT3-EGFP,pHelper 1.0 and pHelper 2.0 by Lipofectamine 2000 to produce lentivirus.2 mL recombinant virus complete culture solution was added according to multiplicity of infection=1,4,8,10,12.The titer of virus was tested according to the expression level of enhanced green fluorescent protein.The control groups were Schwann cells and Schwann cells transfected by no-loaded lentivirus.MAIN OUTCOME MEASURES:The lentiviruses were transduced to Schwann cells,and the transfection efficiency was examined by flow cytometry,the overexpression of hNT3 was determined by Real-time PCR and Western blotting.RESULTS:The exogenous gene sequence of the recombinant hNT3 was completely in accordance with that of its open reading frame in GeneBank.The titer of concentrated virus was 5?107 TU/L.After recombinant LV-hNT3 infection,Schwann cells gave off strikingly bright green fluorescence,and the transfection efficiency amounted to 85%(multiplicity of infection=10).Real-time RCR test showed that the hNT3 mRNA were highly expressed in hNT3-Schwann cells,while did not express in the control group.Western blotting showed the hNT3 expression in Schwann cells.CONCLUSION:Construction of hNT3 gene lentiviral vector can transfect Schwann cells leading to an efficient overexpression of hNT3.

Objective To evaluate the contrast-enhanced 3D sampling perfection with application-optimized contrasts by using different flip angle evolutions-short TI inversion recovery sequence (SPACE-STIR) for the imaging of the post-ganglionic segments of the brachial plexus.Methods Forty-three patients with suspected brachial plexus lesions were examined with 3D SPACE-STIR and contrast-enhanced 3D SPACE-STIR prospectively.Signal-to-noise ratios (SNR),contrast-to-noise ratios (CNR),and the conspicuousness of roots,trunks,divisions and cords of the brachial plexus of the two 3D sequences were retrospectively compared.Statistical analysis was performed by using student t-test and Wilcoxon rank sum test.Results Compared with 3D SPACE-STIR,contrast-enhanced 3D SPACE-STIR provided the similar SNRs (left,37.41 ±7.34 vs 36.27 ±7.66,t =1.574,P =0.123,right,43.85 ±9.56 vs 42.34 ±9.74,t =1.937,P =0.073),but significantly higher nerve-to-muscle CNRs (left,24.01 ± 6.31 vs 26.39 ± 6.95,right,29.31 ± 7.84 vs 31.77 ± 8.85,t =-3.278,-3.278,both P ＜ 0.01) and nerve-to-lymph gland CNRs(left,-0.84 ± 10.51 vs 15.35 ±8.02,right,-8.47 ± 10.85 vs 19.30 ± 10.35,t =-15.984,-15.651,both P ＜0.01).The conspicuousness of roots and trunks on contrast-enhanced 3D SPACE-STIR was significantly better than that on 3D SPACE-STIR (Z =-3.606,-4.472,P ＜ 0.01),while the conspicuousness of divisions and cords was similar(Z =-1.732,-1.414,P =0.083,0.157).The signal intensity of neoplastic lesions on contrast-enhanced 3D SPACE-STIR tended to decrease rapidly,thus the lesion conspicuousness was worse than that on 3D SPACE-STIR.Conclusions Contrast-enhanced 3D SPACE-STIR has obvious advantages in displaying normal brachial plexus and revealing non-neoplastic lesions of the brachial plexus,but may be insufficient for the diagnosis of neoplastic lesions of the brachial plexus.

This study examined the role of PI3K/Akt pathway in radiosensitization of DNA damage of cervical carcinoma cells. The 50% inhibition concentration (IC(50)) of cisplatin and docetaxel in HeLa cells was detected by Mono-nuclear cell direct cytotoxicity assay (MTT) in vitro. HeLa cells were treated by cisplatin/docetaxel of 10 percent of IC(20) alone or combined with LY294002 for 24 h, and then radiated by different doses of X-ray. The cell survival ratio was obtained by means of clone formation. One-hit multi-target model was fitted to the cell survival curve to calculate dose quasithreshold (Dq), mean lethal dose (D(0)), 2Gy survival fraction (SF(2)) and sensitization enhancement ratio (SER). The pAkt and total Akt expression was detected by Western blotting and DNA damage by neutro-comet electrophoresis. The HeLa cells were randomly divided into 7 groups in terms of different treatments: Control; radiation treatment (RT) group; LY294002+RT group; cisplatin+RT group; docetaxel+RT group; LY294002+cisplatin+RT group; LY294002+docetaxel+RT group. The apoptosis ratio of each group was measured by flow cytometry. The results showed that docetaxel and cisplatin significantly enhanced the phosphorylation of Akt in radiation-treated HeLa cells. The Dq, D(0) and SF2 in LY294002-contained groups were lower than those in docetaxel or cisplatin+RT group. The SER in the LY294002+docetaxel+RT group was 1.35 times that of the docetaxel+RT group, and that in the LY294002+cisplatin+RT group 1.26 times that of the cisplatin+RT group. The Comet electrophoresis showed that tail distance in the LY294002+cisplatin+RT group or LY294002+docetaxel+ RT group was longer than in the cisplatin+RT group or docetaxel+RT group. The apoptosis ratio in the LY294002+cisplatin+RT group or LY294002+docetaxel +RT group was higher than in the cisplatin+RT group or docetaxel+RT group. It was concluded that inhibiting PI3K/Akt pathway can increase the effect of docetaxel and cisplatin on the radiosensitivity of HeLa cells and DNA damage resulted from radiation.

ObjectiveTo study the distribution,location and hemodynamics of perforating branches of the ulnar artery with color Doppler flow imaging (CDFI).MethodsPerforating branches of ulnar arteries were examined in 80 healthy volunteers in both forearms using CDFI.Following parameters were detected:number,diameter,jumping-off point,course,location and peak blood velocity.All the parameters data were analyzed statistically.ResultsThree hundred and forty-five perforating branches were detected in total 160ulnar arteries.These branches were classified into three types:type Ⅰ,myocutaneous perforator (10.3 ％);type Ⅱ,septocutaneous perforator(87 ％ ) ; type Ⅲ,direct cutaneous perforator (2.7 ％ ).The most dominant branches were located in the mesial of the upper third,middle third and lower third of the forearm.There was no significant difference among all age groups and no difference in peak blood velocity between left side and right side( P ＞0.05).The peak blood velocity was higher in male than that in female.( P ＜0.05).In relaxing period,the blood flow rate was almost disappeared and the frequency spectrum showed the characteristics of single direction,lower blood velocity and higher blood resistance.ConclusionsCDFI with high resolution showed better results of distribution and location of perforating branches of the ulnar artery and a better quality evaluation of the these branches.CDFI was helpful to design the skin flap containing cutaneous perforators of ulnar artery.

Objective To explore CT features of thin-wall cavity change of pulmonary metastases from renal clear cell carcinoma after molecular targeted treatment and its clinical significance.Methods Clinical and imaging data of 2 patients with thin-wall cavity of pulmonary metastases originating from renal clear cell carcinoma after molecular targeted drug Pazopanib were reported and analyzed retrospectively.Results After resection of primary renal tumors,multiple solid metastatic lesions in the lung were detected and the lesions showed ring enhancement on the post-contrast images.After 3-month Pazopanib treatment,most of the lesions presented thin-wall cavity change.Case 1 showed slowly disease progression while case 2 suffered from spontaneous pneumothorax and died 2 months later.Conclusion Necrosis of pulmonary metastases originated from renal carcinoma can be impelled by molecular targeted Pazopanib treatment,which helped to the formation of cystic thin-wall cavity,but the influence on the prognosis still remains uncertain.

Objective To discuss the value of combining superselective mesenteric angiography (SSMA)with methylene blue in-jection for localization of the Obscure Gastrointestinal Bleeding (OGIB).Methods 12 patients presenting with OGIB had preopera-tive localization of the bleeding site by SSMA.The microcatheter was remained inside the bleeding artery branch after angiography. Then the methylene blue was injected via the microcatheter for localization during exploratory laparotomy and the dyed intestine was then removed.Results The detected rate of bleeding sites by using preoperative SSMA was 100%.The lesions in total 12 patients were found quickly during the exploratory laparotomy.The length of the removed intestine was 9 -12 cm (median,10 cm).After followed up for 10-24 months (median,18 months),all patients with OGIB had no recurrence.Conclusion The method of SSMA combined with the use of methylene blue injection is a safe and effective procedure for the localization of OGIB and could be beneficial for increasing the surgical success rate of hemostasis.

Objective To evaluate the safety and feasibility of laparoscopy in combination with fast track colorectal surgery (FTCS) in the treatment of colorectal cancer in the elderly.Methods A total of 123 patients were randomly divided into 3 groups:the laparoscopy plus FTCS group (n=41),the laparoscopy group (n=41) and the laparotomy group (n=41).Parameters for measuring surgical quality,recovery and postoperative complications were analysed.Results No significant differences were found in age,gender,tumor location,anesthesia ASA classification,American Joint Committee on Cancer (AJCC) Tumor Node Metastasis (TNM) staging,Eastern Cooperative Oncology Group (ECOG) score or complications between the three groups (P＞0.05 for all).There were no differences in blood loss,operative time,time required to resume defecation or number of lymph nodes dissected between the laparoscopy plus FTCS group and the laparoscopy or laparotomy group (P＞0.05 for all),but time taken to initiate postoperative ambulation,time taken to resume flatulence,time taken to start intake of liquid food and length of hospital stay were shorter in the laparoscopy plus FTCS group than in the other groups (P ＜ 0.05 for all).The incidence of postoperative complications was 12.2％ or 5/41 in the laparoscopy plus FTCS group,which was lower than in the laparoscopy group (34.1％ or 14/41) and in the laparotomy group (68.3％ or 28/41) (x2 =5.549 and 28.826,P=0.018 and 0.01,respectively),a statistically significant difference was also found between the latter two groups (x2 =9.567,P =0.002).Conclusions Laparoscopy in combination with FTCS is safe and effective in the treatment of colorectal cancer in the elderly.