OBJECTIVETo evaluate the effect of different subgingival root exposure methods, namely, crown lengthening or forced eruption, and different ferrule lengths on fracture resistance of a residual root restored with a carbon fiber post-and-core system.

METHODSFifty-six extracted endodontically-treated mandibular first premolars were sectioned 1.0 mm coronal to the buccal cementoenamel junction. All the models were divided randomly into seven groups that each consist of eight roots. Group A was given non-ferrule as control. Simulated crown lengthening was performed for the dentin ferrule design in the cervical tooth structure for Groups B, C, and D with a ferrule length of 1.0, 2.0, and 3.0 mm, respectively. Simulated forced eruption was performed with a ferrule length of 1.0, 2.0, and 3.0 mm in the cervical tooth structure for Groups E, F, and G, respectively. After restoration with prefabricated carbon fiber post-and-core system, each specimen was embedded in a self-cured acrylic resin block from 2.0 mm apical to the margins of a cast Ni-Cr alloy crown, then loaded at 150 degrees from the long axis in a universal testing machine at a crosshead speed of 1.0 mm min(-1) until fracture. Data of failure loads and fracture mode were recorded and analyzed.

RESULTSMean failure loads for Groups A to G were (1.13 +/- 0.15), (1.27 +/- 0.18), (1.02 +/- 0.11), (1.05 +/- 0.12), (1.63 +/- 0.14), (1.92 +/- 0.19), and (1.93 +/- 0.15) kN, respectively. The effects of root exposure method and ferrule design differed significantly, and two factors exhibited significant interaction (F=33.396, P<0.0001). When the ferrule lengths were the same, fracture loads in the simulated forced eruption groups were significantly higher than those of the simulated crown lengthening groups (P<0.001). No statistical differences in fracture mode were observed among all groups (P=1.00).

CONCLUSIONMore than 1.0 mm ferrule placement on the apical crown margin by using forced eruption significantly increases fracture resistance.

Purpose To investigate the responsiveness of intracellular oxygen free radical and calcium on acrolein exposure and acrolein-induced cardiomyocytes apoptosis. Methods The viable adult mice cardiac myocytes were isolated by modified langendorff methods. We have examined the intracellular oxygen free radical and calcium concentration using DCF and Fura-2 AM, and the cardiomyocytes viability with WST assay. Are evaluated the DNA ladder pattern and cell apoptotic morphology on the adult mice cardiomyocytes that are exposed to acrolein. Results Our results show that acrolein can increase markedly the intracellular oxygen free radical and calcium concentration, that reach 12 fold and twofold respectively compared to the resting value when the cells were exposed to 1 μmol/L of acrolein. Moreover, the injury induced by acrolein in cardiac myocytes is concentration-dependent. The cardiomyocytes viability treated with 25, 50, 100 μmol/L of acrolein respectively were significantly lower compared to controls (P ＜ 0.01 ). DNA ladder pattern and apoptotic morphological changes were found after being exposed to acrolein in the adult mice cardiomyocytes. Conclusion It is concluded that acrolein induces adult mice cardiomyocytes apoptosis, and it may be due to the increased intracellular oxygen free radicals and calcium concentration.

Objective To study the effect of simvastatin(SV) on NF-kappa B p65 expression in liver of insulin resistant rats. Methods Male Wistar rats were divided into two groups:basic chow(NC,n=15)or high-fat diet(HF,n=20)for 10 weeks feeding, then assessed by euglycemic-hyperinsulinemia clamp technique. Rats in HF group were treated with(HFS,n=5)and without (HFN,n=5) SV 10mgkg-1d-1 in gavage for 5 weeks.NF-kappa B p65 expressions were tested with Western blot. Results The glucose infusion rate (GIR) in HF group decreased significantly compared with NC group (P

Objective To study the association of the serum soluble intercellular adhesion molecule-1(SICAM-1) and soluble vascular cell adhesion molecule-1(SVCAM-1) with metabolic syndrome(MS) and its components. Methods The MS was defined by criteria of the international diabetes federation. The levels of SICAM-1 ,SVCAM-1,plasma glucose,insulin,lipids,uric acid, glycosylated haemoglobin A(1C), and blood viscosity were measured. Results The concentrations of SICAM-1 and SVCAM-1 were significantly higher in subjects with MS and its components than in those without them. The concentrations of SICAM-1 and SVCAM-1 were correlated positively with disorder number of BMI, WHR, SBP, DBP,FPG, 2 hour plasma glucose, triglyceride, uric acid, HbA1c, blood viscosity and HOMA-IR,and negatively with high density lipoprotein cholesterol. Conclusions The concentrations of SICAM-1 and SVCAM-1 rise with the increase of the number of MS components. Endothelial dysfunction might participate in the occurrence and development of MS.

Objective To investigate the difference of serum high sensitivity C-reactive protein(hs-CRP)concentrations in subjects with various glucose tolerances,and to analyze the correlation with insulin resistance.Methods A total of 90 subjects,who came from the Medical Examination Center of the First Hospital Affiliated to China Medical University from Oct.2004 to Apr.2005,were divided into five groups according to oral glucose tolerance test(OGTT):normal glucose tolerance(NGT)group;impaired fasting glucose(IFG)group;impaired glucose tolerance(IGT)group;IFG and IGT(IGT/IFG)group;newly diagnosed,complication-free type 2 diabetes(T2DM)group.By using the ELISA methods,the concentration of serum high sensitivity C-reactive protein(hs-CRP)was measured in these subjects,and its correlation with homeostasis model assessment insulin resistance index(HOMA-IR)was andlysed.Results The concentration of hs-CRP was significantly higher in IFG,IFG/IGT,T2DM than in NGT.The concentration of hs-CRP was positively correlated with glucose metabolism index and insulin resistance index.Conclusion Our study demonstrates that inflammation already exists not only in T2DM patients but also in subjects with IFG.Inflammation might participate in the occurance and development of T2DM.

Aim To study the effect of IL-1β on pro-tein expression of vascular endothelial growth factor in glioma cells and plasma membrane microcapsule struc-ture protein caveolin-1 and plasma membrane vesicles in brain microvascular endothelial cells, and prelimi-narity discuss the possible mechanism of IL-1β opening blood tumor barrier. Methods The tumor barrier mod-el was established by transwell in vitro. The effect of IL-1β on the expression of VEGF in glioma cells and caveolin-1 in brain microvascular endothelial cells was dynamically monitored by Western blot. TEM was used to observe the number of plasma membrane vesicles of brain microvascular endothelial cells. Sodium fluores-cein leakage test was used to assess the permeability of blood tumor barrier after IL-1β. Results The tumor barrier model was successfully established by transwell in vitro. When IL-1β treated the model of blood tumor barrier,the expression of VEGF increased,and reached the peak at 60min,and recovered to the initial state at 120min. The permeability of the blood tumor barrier model was the highest at 60min. In addition,our re-sults also found that,the protein expression of plasma membrane microcapsule structure protein caveolin-1 and number of plasma membrane vesicles in brain mi-crocapsule endothelial cells reached peak at 60 min, subsequently reduced and returned to non drug state at 120min. Conclusion IL-1β increases blood tumor barrier permeability,which may be related to IL-1β in-creasing the number of plasma membrane vesicles through VEGF/ caveolin-1 pathway.

OBJECTIVE:To establish a method for the simultaneous determination of 5 xanthones in Swertia chirayita. METH-ODS:HPLC-EST-MS was conducted. The chromatographic conditions:the column was Waters Symmetry-C18 with mobile phase of water (5 mmol/L ammonium acetate- 0.1% formic acid)-methanol (gradient elution) at a flow rate of 0.8 ml/min,the detection warelength was 254 nm,column temperature was 30 ℃,and the injection volume was 10 μl;MS conditions:it was detected by positive ion,ion source ejection voltage was 4.5 kV,capillary temperature was 200 ℃,capillary voltage was 25 V,sheath gas flow rate was 35 arb,auxiliary gas flow rate was 20 arb,collision gas was helium,and detection method was multi-stage full scan mass spectrometry. RESULTS:The linear ranges for 1-hydroxy-3,5-dimethoxyxanthone,1-hydroxy-3,4,5-trimethoxyxanthone,1, 8-dihydroxy-3,dimethoxyxanthone,1-hydroxy-2,3,4,5-tetramethoxyxanthone and 1-hydroxy-2,3,4,7-tetramethoxyxanthone were all 0.5-15.00 μg/ml(r>0.999 0);RSDs of precision,stability and reproducibility tests were lower than 2%;recoveries were 100.03%-103.59%(RSD=0.99%,n=9)for 1-hydroxy-3,5-dimethoxyxanthone,97.41%-100.89%(RSD=1.15%,n=9)for 1-hy-droxy-3, 4, 5-trimethoxyxanthone, 99.13% -101.68%(RSD=1.40% , n=9) for 1, 8-dihydroxy-3, 5-dimethoxyxanthone, 100.21%-103.51%(RSD=1.33%,n=9)for 1-hydroxy-2,3,4,5-tetramethoxyxanthone,100.56%-103.92%(RSD=1.37%,n=9) for 1-hydroxy-2,3,4,7-tetramethoxyxanthone. CONCLUSIONS:The method is simple,stable and reproducible,and can be used for the simultaneous determination of 5 xanthones in S. chirayita.

Objective To investigate the status and difference of learning burnout between Korean-Chinese nursing students and Chinese nursing students;and to compare the influencing factors of learning burnout between them.Methods A total of 307 nursing students in Yanbian University were recruited by convenience samphng method.Data were analyzed by SPSS 20.0,using descriptive statistics,t-test,ANOVA,correlation analysis,and linear regression analysis.Results The emotion and learning burnout of Korean-Chinese nursing students scored (3.18±0.52)points and (2.84±0.33)points,which were higher than (3.04±0.53)points and (2.69±0.36) points of Chinese nursing students (t=5.72,4.19,all P ＜ 0.05);The significant predictors of learning burnout of Korean-Chinese nursing students were effective commitment,continuance commitment and ideality commitment;and the significant predictors of Chinese nursing students were effective commitment,continuance commitment and behavior self-efficacy.Conclusions Because of the special background of Korean-Chinese nursing students,it is suggested payed attention to improve their major commitment and learning self-efficacy,then to decrease their learning burnout.

Objective To genotype strains producing ESBLs in Escherichia coil and Klebsieua pneumoniae to provide references for the clinical application of drugs.Methods PCR was used to determine the genotype of the ESBLs.Results The percentage of TEM type,SHV type and NO-TEM-NO-SHV type in Escheroichia coil was 80.4%,7.8% and 11.8%,in Klebsieua pneumoniae was 78.1%,71.9% and 25.0%.Most of Klebsieua pneumoniae produced more than two Extended Spectrum ?-lactamases.Conclusion The difference in the distribution of genotypes in different regions is confirmed.

Objective To investigate the effect of different concentrations of TPh on hepatoma cells , cell viability and and its possible mechanisms of anti-tumor.Methods The inhibitory rate of hepatoma cells and cell viability on different concentrations of TPh and time were measured by MTT assay;The morphological changes of apoptosis were observed by Hoechst 33258 straining; Cell cycle distribution was evaluated by flow cytometry (FCM).The protein expression of Bcl-2 and Bax were detected by Western blot analysis.Results MTT assay showed that TPh inhibited the proliferation of HepG-2 cells in a dose-dependent manner, and the inhibitory rate increased with the increase of concentration.The inhibitory rate was 50.9% (P<0.01).The results of Hoechst 33258 staining showed that the fluorescence intensity of hepatocellular carcinoma cells was light blue in fluorescence microscopy and bright blue fluorescence in apoptotic hepatocarcinoma cells, and the apoptosis of hepatocarcinoma cells increased with the increase of drug concentration.The percentage of cells in G0/G1 phase increased with the increase of cell cycle, and the ratio of cells in S phase was decreased in G2/M phase compared with blank control group (P<0.05);Western blot results showed that compared with the blank control group, TPh inhibited the proliferation of Bcl-2 cells in a concentration-dependent manner ( P <0.05 ) , and the number of apoptotic cells increased with the increase of drug concentration (P<0.05), and the ratio of Bcl-2/Bax in the TPh group decreased significantly (P<0.05), and the expression of Bax gene increased. Conclusion TPh inhibits cell proliferation, promotes apoptosis and induces HepG-2 to block G0/G1 phase.Its mechanism may increase the expression of Bax and decrease Bcl-2 protein expression.