BACKGROUND:Implant restoration has become an important means to treat anterior tooth loss,and it is particularly important to select appropriate implant restoration materials.However,at present,there are some deficiencies in clinical implant materials,and researchers have been exploring suitable implant materials.OBJECTIVE:To compare the biomechanical characteristics of implants made of different materials in restoring single missing maxillary anterior teeth.METHODS:The cone beam CT data of a patient with single maxillary central incisor loss were imported into 3-matic software to establish a three-dimensional finite element analysis model of single maxillary anterior tooth loss.The model was then imported into Marc Mentat.Eight sets of implant restoration models were designed according to different implant materials(polyetheretherketone,titanium-zirconium alloy,titanium alloy,and zirconia,with the elastic modulus of the four materials increasing in sequence)and cancellous bone density(high density,low density)to simulate the stress conditions of the maxillary anterior teeth in centric occlusion.The total displacements and von Mises stresses of implants,cortical bone stresses and cancellous bone strains were compared and analyzed.RESULTS AND CONCLUSION:(1)The maximum displacement of the implant gradually decreased with the increase of the modulus of elasticity of the material,and the value of the maximum displacement of the implant in the polyetheretherketone group exceeded 10 μm;the implant stress was concentrated in the labial neck in the models.The maximum stress gradually increased with the increase of the modulus of elasticity of the implant material,among which,the zirconia-low density bone model had the highest stress,which was 21.31 MPa;the cortical bone stress was concentrated in the cortical bone at the junction of the implant with the labial side,and the polyetheretherketone-low density bone group had the highest value,which was 29.90 MPa.(2)From the biomechanical point of view,titanium-zirconium alloy,titanium alloy,and zirconia can be used as implant materials for restoration of a single missing anterior tooth,and implant displacement is one of the common problems during implant restorations,but pure polyetheretherketone material may cause excessive implant displacement in implant restorations of anterior areas,causing implant failure.

BACKGROUND:Implant restoration has become an important means to treat anterior tooth loss,and it is particularly important to select appropriate implant restoration materials.However,at present,there are some deficiencies in clinical implant materials,and researchers have been exploring suitable implant materials.OBJECTIVE:To compare the biomechanical characteristics of implants made of different materials in restoring single missing maxillary anterior teeth.METHODS:The cone beam CT data of a patient with single maxillary central incisor loss were imported into 3-matic software to establish a three-dimensional finite element analysis model of single maxillary anterior tooth loss.The model was then imported into Marc Mentat.Eight sets of implant restoration models were designed according to different implant materials(polyetheretherketone,titanium-zirconium alloy,titanium alloy,and zirconia,with the elastic modulus of the four materials increasing in sequence)and cancellous bone density(high density,low density)to simulate the stress conditions of the maxillary anterior teeth in centric occlusion.The total displacements and von Mises stresses of implants,cortical bone stresses and cancellous bone strains were compared and analyzed.RESULTS AND CONCLUSION:(1)The maximum displacement of the implant gradually decreased with the increase of the modulus of elasticity of the material,and the value of the maximum displacement of the implant in the polyetheretherketone group exceeded 10 μm;the implant stress was concentrated in the labial neck in the models.The maximum stress gradually increased with the increase of the modulus of elasticity of the implant material,among which,the zirconia-low density bone model had the highest stress,which was 21.31 MPa;the cortical bone stress was concentrated in the cortical bone at the junction of the implant with the labial side,and the polyetheretherketone-low density bone group had the highest value,which was 29.90 MPa.(2)From the biomechanical point of view,titanium-zirconium alloy,titanium alloy,and zirconia can be used as implant materials for restoration of a single missing anterior tooth,and implant displacement is one of the common problems during implant restorations,but pure polyetheretherketone material may cause excessive implant displacement in implant restorations of anterior areas,causing implant failure.

【Objective】 To explore and verify the mechanism of curcumin’s inhibition of the proliferation of renal clear cell carcinoma （RCCC） based on network pharmacology and bioinformatics. 【Methods】 We screened common target genes of RCCC and curcumin from PharmMapper and GeneCards databases. We used TCGA database data analysis to screen out common target genes which not only differentially expressed between RCCC tissue samples and normal tissue samples but also affected prognosis. We also used STRING platform to construct curcumin-RCCC targets interaction network， used R software to perform GO biological process analysis and KEGG pathway enrichment analysis based on the above-mentioned screening target proteins. After curcumin and/or active oxygen inhibitor N-acetyl-L-cysteine （NAC） were incubated in renal cancer 786-O and ACHN cells， CCK8 was used to detect the effects of different concentrations of curcumin on cell proliferation and cell viability. Reactive oxygen detection kit （DCFH-DA） was used to detect the level of intracellular reactive oxygen species， and malondialdehyde （MDA） determination kit （TBA method） to detect intracellular malondialdehyde changes. 【Results】 PharmMapper website and GeneCards database screened out 109 common targets of curcumin and RCCC. TCGA database data analysis screened out 37 differentially expressed genes （DEGs） that might affect the overall survival of patients. The core target proteins of curcumin screened out by protein-protein interaction （PPI） that inhibited the biological behavior of RCCC mainly involved CASP3， EGFR， CHEK1， HSP90AA1， and AR. GO enrichment analysis identified 213 items， mainly including reactive oxygen species metabolic process， response to steroid hormones， fibrinolysis and other biologically active processes. KEGG enrichment analysis identified 24 items， which were mainly related to pyruvate metabolism， glycolysis/gluconeogenesis， FoxO signaling pathway， colorectal cancer， tyrosine metabolism， IL-17 signaling pathway， apoptosis and other signaling pathways. Curcumin reduced the cell viability of 786-O and ACHN in a time- and dose-dependent manner （P<0.05）. After curcumin was incubated with kidney cancer cells， the level of reactive oxygen species and MDA increased significantly （P<0.05）. The addition of NAC reversed the effect of curcumin on the cell viability of 786-O and ACHN cells （P<0.05）. 【Conclusion】 Curcumin may participate in the oxidative stress pathway to inhibit the proliferation of renal cell carcinoma.

Objective The aim of this study was to determine whether active part of Glycyrrhiza extract (GL)induced apoptosis in Hela cells and its inhibitory mechanism.Methods HeLa cells were treated with 25 g/mL of GL for 24hs.Cell viability and apoptosis in HeLa cells were determined by MTT,AO/EB fluorescent double staining,transmission electron microscope(TEM),and Western blot.Results The MTT results showed that GL significantly inhibited the proliferation of HeLa cells in a dose-response.After treatment for 24 hrs,large number of early apoptotitc cell were observed using AO/EB fluorescent double staining and TEM.The expression of Pro-caspase-9 and Cleaved-caspase-3 protein was higher in GL-treated cells them those of the control cells(P<0.05).Conclusion GL can activate Caspase-3 and Caspase-9 genes to induce apoptosis in HeLa cells.

Objective To evaluate the value of serum procalcitonin (PCT)on antibiotic use in treatment of community acquired pneumonia (CAP) in outpatient. Methods From November 2006 to February 2008, a total of 127 patients with CAP in outpatient were randomly assigned into two groups:PCT group(n=63)and control group(n =64). PCT levels of all patients were measured after study admission. On the base of similarly normal treatment, the control group received antibiotics according to the attending physicians and the PCT group were treated with antibiotics according to serum PCT levels: antibiotic treatment was applied with PCT level ≥ 0. 25 μg/L and was discouraged with PCT level < 0.25 μg/L. Clinical efficacy, rate of antibiotics use, duration courses and costs of antibiotics were observed. Results Clinical efficacy of the PCT group was similar with the control group (92.1% vs 87.5%, P >0.05) ;rate and costs of antibiotics use was lower, antibiotic duration of the PCT group was shorter than that ofthecontroigroup(P<0.05,P<0.001,P<0.001).Conclusion PCT could be used in treatment of CAP for antibiotic use in outpatient, which may reduce antibiotic use, shorten antibiotic duration and lower costs of antibiotic.

Objective To evaluate the value of serum procalcitonin(PCT)on antibiotics use in treatment of acute exacerbations of chronic obstructive pulmonary disease( AECOPD). Method From May 2004 to December 2006, a total of 235 patients requiring hospitalization for AECOPD were randomly assigned into two groups: standard therapy group(group A, n = 117)and PCT-guided group(group B, n = 118) .PCT levels of all patients were measured after hospital admission by an amplified cryptate emission technology assay. On the base of similarly normal treatment, group A received antibiotics according to the attending physicians,and group B were treated with antibiotics according to serum PCT levels:antibiotic treatment was applied with PCT level ≥0.25 ng/ml and was discouraged with PCT level ＜0.25 ng/ml. Length of hospitalization,clinical efficacy,costs of hospitalization and antibiotics, rate of antibiotics use, hospital mortality,rate of exacerbation and rehospitalization within 1 year were observed. Analyses were performed by t test, Mann-Whitney U test or χ2 test. Results Clinical efficacy, hospital mortality, length of hospitalization, rate of exacerbation and rehospitalization within 1 year were similar in two groups (P =0.635,0.768,0.884,0.747,0.727) ;costs of antibiotics and hospitalization,rate of antibiotics use of PCT-guided group were lower than that of standard therapy group( P = 0.029,0.036,0.014). Conclusions PCT could be used in treatment of AECOPD for antibiotic use after hospital admission,which may reduce antibiotic use and lower costs of antibiotic and hospitalization.

Objective To evaluate the predicting value of serum procaleitonin (PCT) in treatment of acute exacerbations of chronic obstructive pulmonary disease (AECOPD) in elderly patients. Methods A total of 267 elderly patients requiring hospitalization for AECOPD were randomly assigned into 2 groups: standard therapy group (standard group, n= 135) and PCT-guided group(PCT group, n= 132). Standard group received antibiotics according to the guideline of attending physicians and PCT group were treated with antibiotics according to serum PCT levels.Length of hospitalization, clinical efficacy, costs of hospitalization and antibiotics, rate of antibiotics use, hospital mortality, rate of exacerbation and rehospitalization, frequency of exacerbation within 1 year were observed. Results Length of hospitalization, clinical efficacy, hospital mortality, rate of exacerbation and rehospitalization, frequency of exacerbation within 1 year were similar in 2 groups(all P＞0.05);costs of hospitalization and antibiotics, rate of antibiotics use of PCT group[10 882 (3808-16 651)yuan, 6934 (2390-10 660)yuan, 76.5%] were lower than those of standard group[13 637(4650-19 730)yuan, 8589(3144-12 117)yuan, 87.4%] (all P＜0.05). Conclusions PCT guidance offers an advantage over standard therapy in reducing antibiotic use and in lowering the costs of hospitalization in treatment of AECOPD in elderly patients.