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Objective:To study the influences of sucrose,citric acid and sodium bicarbonate on the adhesion of 3 kinds of adhesives.Methods:60 extracted tooth and 60 zirconia blocks (3 mm × 3 mm × 3 mm) were randomly divided into 3 groups (n =20),namely PULPDENT group,3M ESPE RelyxTM Veneer group and RelyxTM Luting group.Then,the samples of each group fell into 4 subgroups(n=5),namely subgroup A for artificial saliva,subgroup B for 10% sucrose,subgroup C for 0.2% citric acid,and subgroup D for 0.03 % sodium bicarbonate.After completing the adhesion of the specimens with corresponding adhesives,the specimens of subgroups A,B,C and D were submerged into artificial saliva(the control),sucrose,citric acid and sodium bicarbonate solutions for 2 times/day and 5 min/time,respectively.For the rest of time,all the specimens were submerged in artificial saliva.3 months later,shear bond strength of the specimens was tested,the fracture surface was observed under SEM,20 × microscope,and the fracture model was observed by stereoscopic microscope.SPSS 17.0 software was adopted for statistical analysis of the data.Results:The bond strength of PULPDENT,3M ESPE RelyxTM Veneer groups were higher than that of RelyxTM Luting group(P < 0.05);the bond strength of subgroups B,C and D was lower than that of subgroup A(P <0.05);and the difference between the remaining groups was not statistically significant(P >0.05).SEM observation displayed that in group RelyxTM Luting,subgroups B,C and D showed increased crack depth,width and length when compared with subgroup A;there was no obvious difference between the remaining groups and the control group;in groups PULPENT,3M ESPE RelyxTM Veneer and RelyxTM Luting,all samples in their subgroups showed interface failure.Conclusion:Compared with PULPDENT and 3M ESPE RelyxTM Veneer adhesive,RelyxTM Luting is more susceptible to the influence of sucrose,citric acid and sodium bicarbonate,so it is not suitable for bonding zirconia blocks.
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Background:The tumor suppressor,X-linked inhibitor of apoptosis(XIAP)-associated factor 1(XAF1)is a XIAP-binding protein that antagonizes the anti-caspase activity of XIAP,thereby enhancing apoptosis. Transcriptional variants of XAF1 have been detected in various tumor cells,however,the expression profile of these transcriptional variants in colorectal neoplasms remains unclear. Aims:To investigate the expressions of XAF1 and its transcriptional variants in different colorectal tissues and their roles in tumorigenesis and development of colorectal neoplasms. Methods:Samples of colorectal cancer and paired adjacent tissue,hyperplastic polyp,adenomatous polyp,and normal colorectal mucosa were collected from surgical operation or endoscopic biopsies. XAF1 protein expression was detected by immunohistochemistry and Western blotting,and the transcriptional variants of XAF1 were detected by RT-PCR. Results:Compared with normal colorectal mucosa,the expression level of XAF1 protein in nucleus was significantly reduced( P 0. 05)in hyperplastic polyp,adenomatous polyp,and cancerous tissue,and the overall expression level of XAF1 protein was decreased(P <0. 05). XAF1A protein expression in cancerous tissue was significantly reduced when compared with the paired adjacent tissue(P < 0. 05). mRNA expressions of three transcriptional variants of XAF1,XAF1A,XAF1B and XAF1C were all significantly lower in neoplastic tissues than in normal mucosa(P < 0. 05). Conclusions:XAF1 and its transcriptional variants are differentially expressed in colorectal neoplasms and normal colorectal mucosa. These changes occurred initially in adenomatous polyp accompanied by a redistribution of XAF1 from nucleus to cytoplasm. Post-transcriptional modification may affect XAF1 gene function.
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<p><b>OBJECTIVE</b>To evaluate the influence of different polishing methods on marginal microleakage of zirconium dioxide full crown.</p><p><b>METHODS</b>Thirty extracted premolars were selected and randomly divided into three groups, A, B and C, with 10 in each group. Group A was prepared with MANI TF-13 bur completely without the treatment of shoulder. The shoulder of group B was polished with MANI TR13-EF bur after the preparation using MANI TF-13. The shoulder of group C was polished with the dental pneumatic ultrasonic hand-piece of KaVo SONICflex after the preparation using MANI TF-13 bur. Five specimens after preparation were selected in each group. Fifteen CAD/CAM zirconium dioxide full crowns have been made. The crowns were bonded using PULPDENT resin cement, and the root canals were sealed using nail polish, and apical foramen were closed using flow resin. The test-pieces have been immersed in a 3% solution of methylene blue for 24 h. The condition of shoulder marginal microleakage was observed using light stereomicroscopy and evaluated in classification index. The remaining specimens in each group were used for roughness test and scanning electron microscope(SEM) experiment. The marginal microleakage situations of specimens in three groups was analyzed by SPSS 17.0. The enamel surface of different polishing methods was observed using SEM.</p><p><b>RESULTS</b>The specimens in group C demonstrated the least marginal microleakage, and those in group B showed an intermediate level of marginal microleakage, and those in group A characterized the most serious marginal microleakage (total, χ2=44.610, P<0.01; among the different groups, P<0.05). The roughness experiment showed that specimens in group C achieve the smoothest results ([0.27±0.03] μm). Preparation shoulder polished using the dental pneumatic ultrasonic hand-piece demonstrated the best result under the SEM among the three groups.</p><p><b>CONCLUSIONS</b>The anti-microleakage effectiveness of dental pneumatic ultrasonic hand-piece in shoulder refinement is better than ordinary shoulder treatment.</p>
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Humanos , Diente Premolar , Diseño Asistido por Computadora , Coronas , Esmalte Dental , Instrumentos Dentales , Filtración Dental , Diagnóstico , Pulido Dental , Métodos , Diseño de Prótesis Dental , Métodos , Selladores de Fosas y Fisuras , Distribución Aleatoria , Cementos de Resina , Ultrasonido , CirconioRESUMEN
<p><b>OBJECTIVE</b>To prepare the polyclonal antibody against methyl-accepting chemotaxis signal transduction protein (MCP) of Helicobacter hepaticus (H.hepaticus).</p><p><b>METHODS</b>The recombinant plasmid pET22b+/MCP was transformed into E.coli BL2l(DE3) to express the fusion protein His-rhMCP under the induction of IPTG. The fusion protein was purified and the antibody was obtained by immunizing rabbits. The titer of the polyclonal antibody was tested by indirect ELISA, and the specificity of the antibody was identified based on Western blotting using the prepared cell surface proteins (CSPs) of the bacteria.</p><p><b>RESULTS</b>The fusion protein was successfully expressed, and the titer of the antibody reached 1:32 000. Western blotting indicated that the antibody could specifically bind to CSPs and His-rhMCP.</p><p><b>CONCLUSION</b>The antibody with a high titer and specificity was prepared to facilitate further study of the pathogenicity and epidemiology of H.hepaticus in human.</p>
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Animales , Masculino , Ratones , Conejos , Anticuerpos Antibacterianos , Genética , Especificidad de Anticuerpos , Proteínas Bacterianas , Alergia e Inmunología , Helicobacter hepaticus , Alergia e Inmunología , Metabolismo , Ratones Endogámicos BALB C , Proteínas Recombinantes de Fusión , Genética , Transducción de SeñalRESUMEN
Objective To explore the effects of polymorphisms of Crohn's disease related NOD2 gene and human beta-defensin 2 (hBD-2) on transcription of hBD-2 gene and its mechanism. Methods HEK293T cells were transfected with hBD-2 gene and NOD2 eukaryotic expression plasmid, and were then stimulated with LPS, TNF-α, or BAY 11-7082 (antagonist of NF-κB), respectively. Transcriptional activity of hBD-2 was detected afterwards. Results LPS could suppress transcription of hBD-2 (P=0. 020), which was increased by TNF-α in a dose-dependent manner (P =0. 004). In the presence of LPS, there was sig-nificant difference in transcriptional activity of hBD-2 between wild-NOD2 transfected group and mutated NOD2 (P268S) transfected group (P=0. 008), but there was no significant difference between wild hBD-2 transfected group and mutated hBD-2 transfected group (P=0. 053). With the stimulation of TNF-α (5 ng/ml), there was a significant difference between mutated hBD-2 transfected group and wild hBD-2 transfected group (P=0. 006), but no significant difference between wild-NOD2 transfected and mutated NOD2 transfected group was defected (P = 0. 064). Pretreatment with BAY 11-7082 before TNF-α (5 ng/ml) significantly inhibited the transcriptional activity of hBD-2 (P < 0. 001). Conclusion The poly-morphism of NOD2 affects the innate expression of hBD-2, the polymorphism of site in hBD-2 promoter (-233) may lead to significant decline of the inducible expression of hBD-2, and NF-κB might be a key pathway that NOD2 protein mediates the expression of defensin.
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Objective To evaluate the clinical manifestations, endoscopic features and the clinical pathological characteristics of H. heilmannii-associated gastritis, and to compare these variables with those of H. pylori-ussociated gastritis. Methods The clinical data, endoscopic findings and pathologic characteristics of 3107 patients, who underwent endoscopy from 2005 to 2007, were retrospectively analyzed. Results Twenty-five cases of H. heilmannii infection were identified, the infection rates of H. heilmannii and H. pylori were 0.80% (25/3107) and 4.12% (1060/3107) respectively. Three cases were mixed infections. Of 25 patients, 20 showed such gastroenterologic symptoms to a greater or less extent as abdominal distending pain,nausea and anorexia, and other 5 cases were asymptomatic. All 25 patients showed chronic gastritis by en-doscopy, including chronic superficial gastritis (7/25, 28% ), erosion ( 3/25, 12% ), chronic atrophic gastritis (4/25, 16%), bile reflux(1/25, 4%), ulcer (1/25, 4%), polyp (1/25, 4%) and duodenal bulbar inflammation (2/25, 8% ). In rapid urease test, 3 cases were hyper-positive, 3 cases positive, 7 ca-ses mild-positive and 12 cases negative. According to histological observation, H. heilmannii scattered or ac-cumulated within the gastric pits, glandular lumen or mucus. The organism was observed in parietal cells with cell damage in one case. Sporadic lymphatic and plasmic infiltration were found in all patients with H.heilmannii infection, infiltration of neutrophils (12/25), gland atrophy and intestinal metaplasia (4/25)and lymphoid follicles (6/25) were also observed. Compared with H. pylori-associated gastritis, H. heilman-nii-associated gastritis showed less inflammation, less helicobacter density, mononuclear cell infiltration and neutrophilic activity ( P < 0.05 ). Conclusion H. heilmanaii mainly induces chronic gastritis, which is less severe than H. pylori-associated gastritis.
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Objective To investigate the association of two single nuclear peptides(SNPs)polymorphisms(rs11209026 and rs11805303)which lies in interleukin-23 receptor(IL23R)gene with susceptibility to inflammatory bowel disease(IBD).Methods The target SNPs were directly sequenced by polymerase chain reaction(PCR)and gene polymorphisms of 50 healthy and 81 patients with IBD (Crohn's disease in 41 patients and ulcerative colitis in 40 patients)were analyzed using chromassoftware.Results The geno-type frequency and allelic frequency of rs11209026 were 7.3%and 3.7%in patients with Crohn's disease respectively,15.0%and 7.5%in patients with ulcerative colitis respectively as well as 14.0%and 7.0%in normal population respectively(all P value>0.05).The geno-type frequency and allelic frequency of rs11805303 were 22.0%and 52.4%in patients with Crohn's disease respectively,15.0% and 41.2% in patients with ulcerative colitis respectively as well as 34.0%and 59.0%in normal population respectively(all P value>0.05).But in allelic frequency there was significant difference between ulcerative colitis patients and normal population(P=0.018).The polymorphisms of rs11805303 loci did not correlate with age,gender,disease duration.activity and site in patients with ulcerative colitis.Conclusions IL23R gene polymorphism is not associated with the susceptibility to Crohn's disease.rs11805303 allele may be related with susceptibility to ulcerative colitis.But no correlation was found between the SNP polymorphisms and the clinical characteristic of ulcerative colitis.
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Aim To investigate roles of ROS in oxaliplatin-induced PUMA expression and apoptosis in colon cancer cells.Methods ROS was used as an oxidative stress in vitro and PUMA expression was determined by Western blot analysis,the apoptosis induced by ROS was assessed by Hoechst 33258 dye staining,the proliferation of the colon cancer cells treated with oxaliplatin and antioxidant was determined by MTT assay.Results ROS induced apoptosis and PUMA expression in colon cancer cells;suppression of PUMA expression by stable transfecting PUMA anti-sense vector decreased apoptosis induced by ROS;oxaliplatin-induced PUMA expression was abrogated by antioxidant and the proliferation of colon cancer cells treated with oxalipla-tin was increased by antioxidant.Conclusions Our data suggests that PUMA and ROS play important roles in oxaliplatin-induced apoptosis.Oxaliplatin induces PUMA expression and apoptosis partly through ROS in colon cancer cells.
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Objective To evaluate the expression of Fas Ligand (FasL) on gastric T cell during H.pylori infection and its cytotoxicity to gastric epithelial cells. Methods FasL protein expressions on mono nuclear cells of gastric mucosa with and without H.pylori infection were examined by immunohistochemistry assay. FasL mRNA expressions were detected in gastric T cell lines isolated from H.pylori infected and uninfected gastric biopsies by RT PCR. The function of FasL expressed by gastric T cells to induce apoptosis in Fas bearing cells was determined by a co culture bioassay (JAM), while the Fas mediated apoptosis of gastric epithelial cells induced by gastric T cells were also evaluated by the same assay. Results FasL was expressed by the mononuclear cells accumulated in gastric mucosa with H.pylori infection, whereas the few mononuclear cells presented in uninfected gastric tissues were negative for FasL. FasL mRNA was detected in gastric T cells isolated from H.pylori infected gastric biopises, while that of uninfected gastric T cell lines was either negative or weak positive. Gastric T cells were capable of inducing apoptosis of Fas positive jurkat cells, while this could be blocked by Fas blocking antibody, ZB4. Conclusions T cells presented in gastric mucosa during H.pylori infection could damage gastric epithelium through Fas/FasL interaction.
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Objective To construct a highly expresses catalase of Helicobacter pylori (H.pylori) and to test it's activity. Methods The catalase DNA was amplified from H.pylori chromosomal DNA by PCR techniques, inserted into the prokaryotie expression vector pET 22b(+) and then transformed into the BL21(DE3) E.coli strain which expressed catalase recombinant protein. Then the activity of H.pylori catalase was assayed by the Beers and Sizers. Results DNA sequence analysis showed that the sequence of catalase DNA was the same as that published by GenBank. The catalase recombinant protein amounted to 24.4% of the total bacterial protein after inducing with IPTG for 3 hours at 37?C and the activity of H.pylori catalase was high in the BL21 (DE3) E.coli strain. Conclusions A clone of expressing high activity H.pylori catalase has been obtained, and thus a good foundation for further study has been laid.
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Objective To study the changes of serum soluble tumor necrosis factor receptor Ⅰ (sTNFR Ⅰ) and immunosuppressive acidic protein (IAP) of patients with pancreatic cancer before and after intra arterial chemotherapy and evaluate their significance. Methods The levels of sTNFR Ⅰ and IAP of 55 cases with pancreatic cancer before and after intra arterial chemotherapy were measured by enzyme linked immunosorbent assay (ELISA) and one direction immunodiffusion test respectively and compared them with those of healthy controls. Results The levels of sTNFR Ⅰ and IAP of patients with pancreatic cancer before intra arterial chemotherapy were higher than those of healthy controls ( P
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Objective To construct a recombinant strain which expresses adhesin AlpA of Helicobacter pylori(H.pylori) and to study the immunogenicity of adhesin AlpA. Methods The adhesin AlpA DNA was amplified by PCR and inserted into the prokaryotie expression vector pET-22b(+)and expressed in the BL21(DE3) E.coli strain. Adhesin AlpA immunogenicity was studied by Western blot test. Results DNA sequence analysis showed that the sequence of adhesin AlpA DNA was almost the same as that of the published by GenBank. The adhesin AlpA recombinant protein accounted for 31.9% of the total bacterial protein. Western blot analysis of rAlpA confirmed that it could be specially recognized by serum from rabbit immunized with AlpA itself and H.pylori infected patients. Conclusion Cloning and high-expression of adhesin AlpA and primary confirmation of its immunogenicity lay the foundation for H.pylori gene engineering vaccine preparation and adhering mechanism research.
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To study the changes in serum immunosuppressive acidic protein (IAP) and T lymphocytes rDNA transcription activity in peripheral blood of patients with pancreatic cancer before and after operation. The level of IAP and T lymphocytes rDNA transcription activity in peripheral blood of 58 patients with pancreatic cancer were measured before and after opreration by one directional immunodiffusion test and a cell image analysis of Ag NORs, respectively, and the results were compared with that of healthy controls. The level of IAP was higher while T lymphocytes rDNA transcription activity was lower before operation compared with healthy controls( P 0 05). The levels of IAP and T lymphocytes rDNA transcription activity were closely related to tumor invasion, metastasis and clinical stages (TNM). Serial determination of the levels of IAP and T lymphocytes rDNA transcription activity might serve as an important index for evalution of tumor invasion and metatasis, and also prognosis for the patients with pancreatic cancer
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To study adhesion of human bifidobacterial strains to cultured human intestinal epithelial cells in vitro mediated by purified adhesin. Results showed that the binding of human bifidobacterial strains to human intestinal epithelial cells appeared to be specific. The adhesion was time and dose-dependent.These data suggested adhesion of human bifidobacterial strains to cultured human intestinal epithelial cells in vitro can be mediated specifically by purified adhesin.
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Objective To investigate the effects of catalase on expression of cytokines and activation of nuclear factor-?B in the intestinal mucosa in rat with ulcerative colitis(UC). Methods UC was reproduced in rats with the oral innoculation of dextran sulfate sodium (DSS).The expressions of TNF-?, IL-1? and IL-8 in the intestinal mucosa of rats were respectively determined by a semi-quantatitive assay, RT-PCR. The activation of NF-?B in the intestinal mucosa were assessed with electrophoretic mobility shift assay (EMSA). Results Comparing the mice challenged with DSS alone and to those treated with catalase, both symptoms and the lesions in the colonic mucosa were milder in the animals pretreated with catalase during the induction of colitis than that of control group and catalase treatment after induction of colitis group. Furthermore, the expressions of TNF-?, IL-1?, IL-8 were significantly down-regulated(P
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Background and purpose:The Smac/DIABLO(the second mitochondrial derived activator of caspase/direct IAP binding protein with low pI)is a new kind of mitochondria protein,it inhibits IAPs(inhibitors of apoptosis protein),including Survivin,and activates caspase-9 and caspase-3,accordingly promotes apoptosis.In this study,we investigated the effect of over-expressing mitochondrial protein-Smac/DIABLO while silencing inhibitor of apoptosis protein-Survivin on the cell growth,cell cycle and apoptosis of human colon cancer cells through cotransfecting both genes.Methods:Constructed survivin-shRNA-EGFP plasmid was transected with Smac-pcDNA3.1 plasmid into Lovo cells at either half each dose or total dose,respectively.Western blot was used to survey the protein level of Smac and Survivin;Hoechst 33258 staining was used to detect the karyomorphological diversity of apoptotic cells and evaluate apoptotic ratio roughly;PI staining and flow cytometry analysis were used to examine cell cycle;caspase-3 Detection Kits was used to detect the activity of caspase-3.Results:The expression of Smac protein increased but Survivin protein decreased 48 hr after transfection.Karyomorphological diversify of apoptotic cells were obviously observed by hoechst 33258 staining.The apoptosis rate in Smav+Survivin shRNA group was(18.5?1.7)%,which was higher than that in Smac group(9.6?1.8)% and Survivin shRNA group(15.0?0.3)%,and all of three groups were significantly higher than the control groups;The cells of G0/G1 phase increased to(51.0?6.2)% in Smac group,and the cells of S stage increased to(53.3?1.3)% in Survivin shRNA group(P