OBJECTIVES: To investigate the efficacy of Ag₂Se nanoparticles for eliminating intracellular Porphyromonas gingivalis (P. gingivalis) in esophageal cancer and examine the effect of P. gingivalis clearance on progression of esophageal cancer. METHODS: Ag₂Se nanoparticles were synthesized via a chemical synthesis method. The effects of Ag₂Se nanoparticles on P. gingivalis viability and colony-forming ability were assessed using fluorescence staining and colony formation assays. In a mouse model bearing subcutaneous murine esophageal cancer cell allograft with P. gingivalis infection, the effect of treatment with Ag₂Se nanoparticles on the abundance of P. gingivalis in the tumor tissues was quantified using RNAscope in situ hybridization and quantitative polymerase chain reaction (qPCR), and the changes in tumor volume were monitored. The biosafety of Ag₂Se nanoparticles was assessed by examining liver and kidney functions and pathological changes in the major organs of the mice. RESULTS: Transmission electron microscopy revealed that the synthesized Ag₂Se nanoparticles were uniformly dispersed spherical particles with a diameter around 50 nm. In vitro experiments demonstrated that exposure to Ag₂Se nanoparticles significantly reduced the viability and clonal proliferation capacity of P. gingivalis in a dose-dependent manner. In the tumor-bearing mice, treatment with Ag₂Se nanoparticles significantly reduced the abundance of P. gingivalis in tumor tissues and suppressed tumor cell proliferation. No significant damages to the liver and kidney functions or the major organs were observed in Ag₂Se nanoparticle-treated mice, demonstrating good biocompatibility of Ag₂Se nanoparticles. CONCLUSIONS Ag₂Se nanoparticles exhibit significant bactericidal and inhibitory effects against P. gingivalis, and can effectively eliminate intracellular P. gingivalis to suppress the growth of esophageal cancer allograft in mice, suggesting the potential of Ag₂Se nanoparticles in the treatment of esophageal cancer.
Animals ; Porphyromonas gingivalis/drug effects* ; Mice ; Esophageal Neoplasms/pathology* ; Nanoparticles ; Metal Nanoparticles ; Bacteroidaceae Infections ; Cell Line, Tumor

Objective:To compare quantitatively the quality of the canal isthmus retropreparation among three kinds of ultrasonic ret-rotips.Methods:1 20 maxillary bicuspid teeth with two canals and an isthmus were randomly assigned to 3 groups(n=40).The canal isthmus retropreparation were made respectively using ultrasonic niti tip RE2,diamond tip Berutti and #25K file.Image processing and analysis system were used to measure the preoperative and postoperative parameters for further evaluation.Results:The cutting volume of ultrasonic niti tip RE2 group was significantly less than those of other two groups(P<0.05).Conclusion:Ultrasonic niti tip RE2 is feasible in the canal isthmus retropreparation.

Objective:To compare the quality of the canal isthmus retropreparation among three ultrasonic retrotips.Methods:120 maxillary bicuspid teeth with 2 canals and an isthmus were randomly assigned to 3 groups(n =40).The canal isthmus were retro-preparated by ultrasonic Ni-Ti tip RE2,diamond tip Berutti and #25K file respectively.The quality of cavity margin,the number and type of the micro-cracks were evaluated by SEM.Data were statistically analysed by Kruskal Wallis Test of SPSS 13.0.Results:The cavity margin quality of ultrasonic Ni-Ti tip RE2 group was superior to that of other 2 groups(P =0.003);The number of micro-crack in Ni-Ti tip RE2 group was less than that of other 2 groups(P =0.003).The type of micro-cracks has no significant difference among the 3 groups(P =0.830).Conclusion:Ultrasonic Ni-Ti tip RE2 is feasible in the canal isthmus retropreparation.

Objective:To compare the quality of root-end preparation quantitatively between ultrasonic retrotips and traditional slow-speed handpiece. Methods: 27 maxillary second bicuspid teeth with two canals and an isthmus were randomly assigned to 3 groups.Root-end preparations were made respectively using ultrasonic diamond tip Berutti and niti tip RE2, ultrasonic 40~#K file and slow-speed handpiece with No.2 round bur. Image processing and analysis system were used to measure the preoperation and postoperation parameters for further evaluating the difference between the two techniques. Results: The cutting volume of ultrasonic instruments was less than slow-speed handpiece(P<0.000 1). Conclusion: Ultrasonic instrument is better in the root-end preparation than traditional slow-speed handpiece.

Objective To characterise the alterations of serum autoantibodies for cyclinB1,p62,Koc-IMP1 and survivin in the subjects with esophgeal and gastric cardia carcinoma and precancerous lesion and their expres-sions in the esophageal and gastric cardia cancer tissue.Methods Enzyme-linked immunoassay and tumor-associated antigen mini-array (consisting of five full-length recombinant proteins,including eyefinB1-p62-Koc,IMP1 and Survivin)were applied to determine the serum level of the autoantibodies of these antigens on 376 subjects with e-sephageal and gastric cardia carcinoma and precancerous lesions.At the same time,the expression of these antigens was detected by immunohistochemical method(ABC)on 13 patients with esophageal cancer and 16 with gastric car-dia cancer.Results All of the 5 antigens determined,the linear correlation Was observed for the detection frequency of cyclinB1,IMPI and p62 in esophageal carcinogenesis,and for p62 in gastric cardia multi-stage progression from normal to precancerous and cancerous lesions(P<0.05).The detection rale with single positive antoantibody im-munoreactivity for both esophageal and gastric cardia cancers were low.However.the positive detection mte for both esophageal and gastric cardia cancer increased apparently when the multiple positive markers were combined together for analysis,which increased tO 3～5 and 3～4 folds respectively.Furthermore,the difference in autoantibody immu-noreactive rate was significant with the lesion progressed from mild tO severe precancerous lesions and to cancer both in esophageal and gastric cardia cancers(P<0.05).The positive immunoreactions of the 5 antigens were detected in cancer tissues.The positive immunostaining rates for cyclinB1,Koc,IMP1 and Survivin both in esophageal and gastric cardia cancers were higher compared to their serllin positive rate of autoantibodies I P<0.05).Of the pa-tients with positive immunostaining in the two cancer tissues,the autoantibodies in the serum for the corresponding antigens could be detected in the same patient.Conclusion The production of the tumor-associated autoantibodies is related tO antigens.The screening rate through serum tumor-associated antigen mini-array for the patients with e-sophageal and gastric cardia carcinoma and precancerous lesions has been increased apparently with combined analy-sis of multiple autoantibodies than with single one.

Objective:To compare the quality of root-end preparation quantitatively between ultrasonic retrotips and traditional slow-speed handpiece.Methods:27 maxillary second bicuspid teeth with two canals and an isthmus were randomly assigned to 3 groups.Root-end preparations were made respectively using ultrasonic diamond tip Berutti and niti tip RE2,ultrasonic #40K file and slow-speed handpiece with No.2 round bur.Image processing and analysis system were used to measure the preoperation and postoperation parameters for further evaluating the difference between the two techniques.Results:The cutting volume of ultrasonic instruments was less than slow-speed handpiece(P