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OBJECTIVE To co mpare the difference of liposoluble constitue nts in different processed products of Huaizhong No.1 Rehmannia glutionsa （fresh R. glutionsa ，R. glutionsa and prepared R. glutionsa ），and to evaluate its in vitro antioxidant activity preliminarily. METHODS Liposoluble extracts were extracted from 3 processed products of R. glutionsa by Soxhlet extraction. Their constituents were analyzed by gas chromatography-mass spectrometry. The spectral library of NIST 98 system was used to automatically retrieve the mass spectrum information of components ，and the structures of compounds were identified in combination with relevant literature and by comparing with eight peak index and EPA/NIH library. Relative contents of the components were calculated by using peak area normalization method with Hewlett Packard software. The antioxidant activities of liposoluble constituents in 3 processed products of R. glutionsa were investigated by 1，1-diphenyl-2-picrylhydrazyl（DPPH）free radical scavenging. RESULTS A total of 79 liposoluble components were identified from different processed products of R. glutionsa，and 48，52 and 37 liposoluble compounds were identified from fresh R. glutionsa ，R. glutionsa and prepared R. glutionsa，respectively；their relative contents accounted for 92.69％，86.29％，92.89％ of the total components respectively. Among them ，there were 20 liposoluble compounds totally ，and their relative contents accounted for 88.73％，80.89％ and 85.87％ of liposoluble components in each processed product respectively ；they were mainly composed of fatty acids such as methyl linoleate，methyl palmitate and methyl oleate. In addition ，there were 18 unique liposoluble components in fresh R. glutionsa ， mostly terpenoids ；there were 17 and 6 unique liposoluble components in R. glutionsa and prepared R. glutionsa ，mostly alkanes. The results of antioxidant experiment showed that median scavenging concentrations of liposoluble components to DPPH limeng free radical were 0.756，0.660，0.758 mg/mL，respectively. CONCLUSIONS The common liposoluble components in different processed products of R. glutionsa are mostly acids；the unique liposoluble components in fresh R. glutionsa are mostly terpenoids ，and those of R. glutionsa and prepared R. glutionsa are mostly alkanes ；the liposoluble constituents possess in vitro antioxidant activities.
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OBJECTIVE： To establish HPLC fingerprints of Paeonia tactilora decoction pieces， and to conduct its cluster analysis and principal component analysis. METHODS： HPLC method was adopted. The determination was performed on SunFire® C18 column with mobile phase consisted of acetonitril-0.05％ phosphoric acid solution （gradient elution） at the flow rate of 1.0 mL/min. The detection wavelength was set at 230 nm， the column temperature was 30 ℃， the collection time was 70 min，and sample size was 15 μL. Using paeoniflorin as reference， HPLC fingerprints of 26 batches P. tactilora decoction pieces from different habitats and 30 batches by different processed methods were established. The similarity of samples was evaluated by TCM Chromatographic Fingerprint Similarity Evaluation System （2012 edition） to confirm common peak. Cluster analysis and principal component analysis were performed by using SPSS 20.0 software. RESULTS： There were 9 common peaks in HPLC fingerprints of 26 batches of sample from different habitats， the similarity of which was higher than 0.880. Six peaks were identified， including gallic acid， catechin， albiflorin， paeoniflorin， 1，2，3，4，6-pentagalloylglucose and benzoylpaeoniflorin. Cluster analysis showed that 26 batches of samples were clustered into 2 categories when cosine distance was 15. S1-S21 were clustered into one category； S22-S26 were clustered into the other category. By principal component analysis， the accumulative contribution rate of two main components was 81.124％. There were 10 common peaks in HPLC fingerprints of 30 batches of sample by different processed methods， the simi- larity of which was higher than 0.970. Seven peaks were identified， including gallic acid， catechin， aplopaeonoside， albiflorin， paeoniflorin， 1，2，3，4，6-pentagalloylglucose and benzoylpaeoniflorin. Cluster analysis showed that 30 batches of samples were clustered into 2 categories when cosine distance was 25. B1-B10 were clustered into one category； C1-C10 and J1-J10 were clustered into the other category. By principal component analysis， the accumulative contribution rate of four main components was 86.887％. CONCLUSIONS： Established HPLC fingerprint， the results of cluster analysis and principal component analysis can provide reference for quality control of decoction pieces of P. tactilora.
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Objective:To investigate the ability of fluoride toothpaste and fluoride varnish on enamel remineralization and acid resist-ance.Methods:Enamel specimens were prepared from bovine incisors,and were randomly divided into 4 groups(n=3)after acid-etching by 37%phosphoric acid.Specimens in group A(control)was processed daily with normal saline;those in group B and C were treated once with Duraphat varnish and Fluor Protector varnish respectively;in group D was daily processed with fluoride toothpaste. All specimens were incubated in artificial saliva for 2 weeks.Then all specimens received acid-etching again.Micro-hardness test, SEM observation and image analysis were performed before and after each step.Results:After 2 weeks of processing,no remineraliza-tion was found in group A.Varnish layers were observed on the surface of specimens in group B and C.In group D remineralization was detected on the enamel surface.After re-etching,micro-hardness decreased in group A and D.Fluoride varnish layers in group B and C showed strong resistance to acid-etching.After re-etching,area of micro-holes in group A and D increased(P<0.05 ),but that in group D was smaller than in the control(P<0.05).No micro-hole was observed in group B and group C.Conclusion:Protec-tive layer formed on the enamel surface by fluoride varnish is resistant to acid-etching and promotes enamel remineralization.Fluoride toothpaste application can promote enamel remineralization,but with less resistance to acid.
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Objective; To investigate the immunolocalization and significance of Notch-2 expression in the process of dental pulp repair after injury. Methods: An experimental animal model of injury-induced pulpitis was established to observe the time-sequenced alteration of the expression of Notch-2. Results: Three days post-operation, weak positive staining of Notch-2 was observed in pulp mesenchyme cells and pulp fibroblasts but not in vascular endothelial cells or odontoblasts. Five days post-operation, strong Notch-2 reactivity was found in subodontoblasts as well as newly bom capillary endothelial cells. Seven days after cavity preparation, Notch-2 staining became weaker in pulp mesenchyme cells and capillary endothelial cells, but stronger positive staining was found in odontoblasts. Two weeks post-operation, weak Notch-2 staining was seen in pulp mesenchyme cells and subodontoblastic layer cells and was absent from odontoblasts. Notch-2 immunoreactivity was completely absent in intact rat dental pulp. Conclusion: Notch-2 is strikingly up-regulated in dental pulp mesenchyme cells in the early days after dental injury and then shows progressively up-regulation in odontoblasts. Properly regulated activation of Notch signaling pathway is important for controlling cell fate and maintaining the correct balance among cell proliferation, differentiation and apoptosis during dental pulp repair process.