[Chemical Constituents from Shoot of Phyllostachys edulis (II)].

OBJECTIVE: To investigate the chemical constituents from the shoot of Phyllostachys edulis. METHODS: Normal-phase, reversed-phase silica gel, Sephadex LH-20 porous polymer gel column and HPLC chromatography were used for isolation. Spectroscopic methods (13C-NMR, 1H-NMR, DEPT and EI-MS) were used for identification. RESULTS: Eleven compounds were isolated and elucidated, which were skimmin(I), liquiritienin(II),1-(4-hydroxy-3-methoxyphenyl)-1-propanone(III), syringicaldehyde(IV), vanillin(V), isoliquiritigenin(VI), 4-hydroxybenzoic acid(VII), methyl p-hydroxy benzeneacetate (VIII), 5,7-dihydroxy-8-methoxyflavone (IX), daucosterol(X) and ß-sitosterol(X). CONCLUSION: All the compounds are obtained from this plant for the first time, and compounds VI, VIII and IX are firstly isolated from the plants of this genus.

[Experimental investigation of shear bond strength on orthodontic bonding on dental fluorosis after air abrading surface preparation technique].

OBJECTIVE: To find a way to having higher bond strength on mottled enamel. METHODS: Sixty mottled enamel first bicuspid teeth extracted from fifteen patients needing orthodontic force were prepared and divided into four groups. Group A was routine acid etched, group B was air abraded, group C was etched by clearfil liner self-etching primer, group D was air abraded and then etched by clearfil liner self-etching primer. Next the bond and resin were used. The shear bond strength was observed and compared. The data were analysed by SPSS 11.5 statistical package. RESULTS: The shear bonding strength of group A was (2.247 +/- 0.261) MPa, group B was (5.374 +/- 0.469) MPa, group C was (4.345 +/- 0.401) MPa, group D was (5.791 +/- 0.636) MPa. The strengths of four groups were significantly different (P < 0.01). The adhesive remnant index (ARI) scores of the four groups had no significant difference. CONCLUSION: In clinic, using air abrasion surface preparation technique is an acceptable way to enhancing the shear bond strength before sticking the orthodontic bonding on dental fluorosis.