Objective To observe and compare the analgesic effects of electro-acupuncture(EA)of “Tsusanli point” (St. 36) with various stimulation parameters. Methods Single wide dynamic range (WDR) and nociceptive specific (NS) neurons were recorded extracellularly in the dorsal horn of the rat lumbar spinal cord. The late train discharges (C-response) of the neurons evoked by intense electrical stimulation of the skin were used as a nocicepive response. The inhibitory effects of EA stimulation of the “Tsusanli point” (St. 36) with various intensities (1 and 6 mA) and frequencies (5, 20, 50 and 100 Hz) on the C-response were observed, respectively. Results A lower frequency (5 Hz) was appropriate to the high-intensity EA, while a higher frequency (50 Hz) was proper for the low-intensity EA. Conclusion The effect of EA on the spinal nociceptive transmission is both intensity- and frequency-dependent.

Background and purpose:The genesis and progression of cervical cancer are closly related to E6 and E7 oncogenes of HPV.Special ribozyme and antisense oligonucleotide could inhibit the expression of E6 or E7.but both of them were not the best methods.The aim of this study was to investigate the inhibitive effect of chemically synthetic siRNA on E6 gene in the cervical cancer cell line SiHa and the following biological changes of SiHa cells.Methods:Three specific siRNAs targeting to HPV16 E6 were synthesized and transfected into SiHa cells by lipofectamine.The level of E6 mRNA was tested by RT-PCR,proliferation activities,the cell cycle distribution,expression of p53 protein and the ultramicrostructure changes of SiHa cells were detected by MTT,FCM,immunochemistry and TEM respectively.Results:All the 3 siRNAs could inhibit the level of E6 mRNA singificantly,among which siRNA1 was most effective.Decreased cellular proliferation activity was observed by MTT,especially when the cells were transfected with siRNA1 at 50 nmol/L concentration.Flow cytometry revealed obvious G1 arrest in cell cycle.The expression of p53 protein in transfected cells(0.75?0.06)was increased compared to the control group(0.43?0.03),the difference was singificant.Cell-substance concentration and vacuolus were found in endochylema by TEM.Conclusions:Chemically synthetic siRNA can interfere in the expression of E6 mRNA in SiHa cells specifically and induce the biological changes of the target cells.

Objective:To compare the durability of resin-based root-surface coating material and all-in-one self-etching adhesive on root surface in vitro.Methods:Human extracted premolars or molars with intact roots were selected.The cementum was removed using a periodontal scaler to expose root dentin. The root surface was coated with an acid-resistant nail varnish,leaving a window of 3 mm ×3 mm on the exposed dentin.The window was covered with either PRG Barrier Coat (PRG)or Clearfil S3 Bond (CS3).After water aging for 14 d,specimens were immersed in acid buffer at pH 4.5 for 4 d and the demineralization buffer was changed every 24 h.Then the specimen was split longitudinally through the center of the ‘window’and the cross-sectional surface was observed with scanning electron microscope (SEM).After fixed and dehydrated,the prepared samples were coated with platinum.The coating mate-rial,root dentin and the interface was observed by scanning electron microscope (SEM).The thickness of the coating material was measured on the SEMimages.Regarding toothbrush wear test,coronal dentin-disks were prepared and covered with PRG and CS3,respectively.After storage in water for 24 h,the specimen was subjected to the toothbrush wear tester for 100,200,300,500,700,1 500 brushing cy-cles.A slurry of fluoride toothpaste (1 ∶2 ratio of toothpaste and deionized water by weight)was used and the brushing load was 300 N.The surface microstructure of remaining coating material was analyzed using SEM.The wear depths were determined by a profilometer.Statistical analysis was performed with SPSS 20.0 by one-way ANOVA.The level of significance was at 0.05.Results:Application of PRG Barrier Coat produced a coating layer of (47.1 ±27.3)μm,while CS3 presented a thin film of (5.7 ± 2.1)μm in thickness.The exposed dentin was hermetically sealed and no obvious gap was observed at the interface in both PRG and CS3 groups.There was no dentin demineralization observed in both groups after water aging.The wear depths of PRG and CS3 increased along with the numbers of brushing cycles. PRG wore at a significant lower pace than CS3 did (P <0.05).Conclusion:PRG coating resin had similar performances as CS3 on protecting root dentin from demineralization after water aging.What’s more,PRG demonstrated a higher toothbrush wear resistance than CS3.We concluded that PRG Barrier Coat contained S-PRG filler may be an effective coating material for protecting exposed root from both chemical and mechanical challenges.Further studies should be carried out to evaluate the long-term reli-ability of the rootsurface coating materials under the clinical setting.