Objective:To evaluate the effects of different denture cleaners on the discoloration of heat-cured denture base resin and artificial teeth.Methods:40 same specifications of the heat-curing denture base resin and 40 artificial central incisors were immerced in an acombination stain of coffee,tea and soy sauce for 4 weeks.Then specimens and artificial teeth were randomly distributed into 4 groups and soaked in Polident,Steradent,0.5％ sodium hypochlorite solution and distilled water for 4 hours respectivelly(n =10).Color differences(△E) were measured by using a colorimeter and a denture spectrophotometer before and after staining,and after cleaning.Results:Before or after staining there was no difference of △E among the groups of denture base risn or artificial teeth(P ＞ 0.05).After cleaning the denture base resin and the artificial teeth in the group of 0.5％ sodium hypochlorite solution presented higher △E than the other groups(P ＜ 0.05),in group of distilled water presented lower △E than the other groups(P ＜ 0.05).No significant difference was found between Polident group and Steradent group(P ＞0.05).The △E of the denture base resin and artificial teeth.in distilled water group before staining and after cleaning were the highest among the groups(P ＜0.05).Conclusion:0.5％ sodium hypochlorite solution,Polident and Steradent are effective in removing the discoloration from the heat-cured acrylic resin and artificial teeth.0.5％ sodium hypochlorite solution is the most effective,Polident and Steradent are the similar.

Objective To investigate the protective effect and mechanism of J147 on the injury of human neuroblastoma cells(SH-SY5Y)induced by high glucose(HG).Methods We established HG-induced SH-SY5Y cell injury model.Then SH-SY5Y cells were divided into blank control(Con)group HG group,HG+J147 0.5 μmol/L(HG+J147 0.5)group,HG+J147 1 μmol/L(HG+J147 1)group,HG+J147 2 μmol/L(HG+J147 2)group,HG+PI3K/AKT inhibitor LY294002(LY)10 μmol/L(HG+LY)group,HG+ERK1/2 inhibitor U0126(U0)5 μmol/L(HG+U0)group,HG+J147 2 μmol/L+LY 10 μmol/L(HG+J147 2+LY)group,HG+J147 2 μmol/L+U0 5 μmol/L(HG+J147 2+U0)group.Cell viability was detected by MTS cell proliferation and toxicity detection kit;LDH activity was tested by lactate dehydrogenase kit;morphological changes of SH-SY5Y cells were evaluated by microscope;cell apoptosis was detected by flow cytometry;and apoptosis-related proteins(Bcl-2,Bax)and signaling pathway-related proteins(p-AKT,AKT,p-ERK1/2,ERK1/2,p-CREB,CREB,BDNF)were detected by Western blot.Results Compared with Con group,the cell viability,Bcl-2/Bax ratio,p-AKT/AKT,p-ERK/ERK,p-CREB/CREB and BDNF protein expressions decreased(P<0.01),while LDH activity and apoptosis rate increased in HG group(P<0.01).Compared with HG group,the cell viability,Bcl-2/Bax ratio,p-AKT/AKT,p-ERK/ERK,p-CREB/CREB and BDNF protein expressions increased(P<0.01),while LDH activity and apoptosis rate decreased in HG+J147 2 group(P<0.01).Compared with HG+J147 2 group,the cell viability,Bcl-2/Bax ratio,p-AKT/AKT and BDNF protein expression decreased(P<0.05 or P<0.01),while LDH activity and apoptosis rate increased(P<0.05 or P<0.01),the expression of p-ERK/ERK protein in HG+J147 2+LY group decreased(P<0.05),and the expression of p-CREB/CREB protein in HG+J147 2+U0 group decreased in HG+J147 2+LY and HG+J147 2+U0 groups(P<0.05).Conclusions J147 can alleviate HG-induced SH-SY5Y cell damage,and the mechanism may be related to the activation of PI3K/AKT and ERK1/2 signaling and the reduction of apoptosis.