Biomodifying effect of epigallocatechin-3-gallate on dentine substrate splicing surface / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To investigate the effect of epigallocatechin-3-gallate (EGCG) on biomodification of demineralized dentine substrate, in its permeability, hydrophobicity, and inhibition ability to collagen enzymatic degradation.</p><p><b>METHODS</b>The dentine substrates were treated with simulated pulpal pressure created by mixtures of 0.02%, 0.1% EGCG/bovine serum albumin (BSA) in acidic environment (pH4.4) for 48 h. A fluid-transport model was used to measure the fluid permeability through demineralized dentine substrate. Positive replicas of dentine substrate were fabricated before and after being subjected to acidic environment for scanning electron microscope (SEM) examination. The blank group contained no EGCG and the positive group were treated with Gluma desensitizer. Static contact angle measurements on demineralized dentin and 0.1% EGCG primed dentin were performed by contact angle analyzer. The priming time were 60 s, 120 s, 0.5 h, 1 h. Dentine specimens bonded with Adper single bond 2 were subjected to 100 mg/L collagenase and observed under SEM. Resin-bonded specimens (with 0.02%, 0.1%, 0.5% EGCG priming, or without EGCG priming) were created for micro-tensile bond strength evaluation (MTBS). Resin-bonded specimens after thermol cycling were created for MTBS evaluation.</p><p><b>RESULTS</b>The fluid permeability in the blank control group increased ([151.3±22.3]%), the fluid permeability in 0.1% EGCG/BSA group decreased ([23.7±6.3]%). Compared to the blank control group, the contact angle of 120 s, 0.5 h, 1 h groups increased by 31.0%, 53.5%, 57.8% in deep dentin and 37.4%, 59.3%, 62.4% in shallow dentin. The SEM examination showed that 0.1% and 0.5% EGCG priming for 120 s significantly increased dentin collagen's resistance to collagenase. The immediate MTBS of 0.1% and 0.5% EGCG groups were (29.4±4.8) and (19.8± 4.9) MPa. After thermol cycling, the MTBS of 0.1% and 0.5% EGCG groups were (19.9±5.1) and (15.3± 6.3) MPa.</p><p><b>CONCLUSIONS</b>Under acidic environment (pH4.4), the 0.1% EGCG can reduce dentine permeability under acidic environment. The 0.1% EGCG can increase hydrophobicity of dentin substrate, and strengthen dentin substrate's resistance to collagenase hydrolysis, thus increased the resin-dentin bonding durability.</p>

Sealing properties of three resin-based sealers / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To evaluate the sealing properties of three resin- based sealers, EndoREZ, RealSEAL and RealSEAL SE.</p><p><b>METHODS</b>Forthy-eight extracted human anterior teeth with single root and canal were prepared using ProTaper files with crown-down technique to F3. The teeth were filled with three sealer respectively with hot gutta- percha vertical condensation technique simulating the clinical situation. Leakage quantity was detected using computerized fluid filtration meter with 10 samples in each group. The cross section morphology of apical parts of roots of 5 mm was observed with scanning electron microscope and transmission electron microscope in 3 samples of each group, respectively.</p><p><b>RESULTS</b>The leakage quantity of EndoREZ, RealSEAL and RealSEAL SE were (2.61±0.60), (1.43±0.11) and (1.76±0.18) µl/min, respectively. The gaps between the the sealer and the canal wall were increased in in order of RealSEAL, RealSEAL SE and EndoREZ. No obvious demineralized dentin under EndoREZ and the smear layer was not completed removed. The partly demineralized dentin was observed under RealSEAL and the smear layer was totally removed. The partly demineralized dentin was seen under RealSEAL SE and the majority of smear layer was removed.</p><p><b>CONCLUSIONS</b>Among the three resin- based sealers, RealSEAL has the best sealing properties, followed by RealSEAL SE and EndoREZ.</p>

The Role of Calcium Ion in Effects of Arecoline Hydrobromide on Contractive Activities of the Smooth Muscles in Oncomelania Foot / 医药导报

To investigate the relationship between the effects of arecoline hydrobromide on contraction of the smooth muscles in oncomelania foot, and explore the mechanism of arecoline hydrobromide in decreasing climbing adhesion and increasing snail－killing. 　Method: The in vitro experiment was used to observe the effects of arecoline hydrobromide on contraction activitive of foot smooth muscles of oncomelania. 　Results: With a concentration of 3×10-6mol*L-1, arecoline hydrobromide strengthened the contraction and increased the frequency of the contraction of the foot smooth muscles of oncomelania, which was antagonized by verapamil. The same concentration of arecoline hydrobromide enhanced the contraction of smooth muscles in Ringer's solution with ECTA but Ca2+, and this effect was antagonized by caffeine. The concentrations of 10－5 and 3×10－5mol*L-1 of arecolin hydrobromide blocked the effect of Bay K8644 in enhancing foot smooth muscle contraction, with a characteristic of concentration－dependence. 　Conclusion:Arecoline hydrobromide may block the calcium channel of the smooth muscles in oncomelania foot. This could provide an explanation why arecoline hydrobromide decreases the rate of oncomelania climbing adhesion and enhances snail－killing.

Researches on Service Marketing of Pharmaceutical Enterprises from the Perspective of Pharmaceutical Characteristics / 中国药房

OBJECTIVE:To discuss what service marketing strategies the pharmaceutical enterprises in China should choose in the face of more and more fierce competition in pharmaceutical markets.METHODS:The service characteristics of both prescription drugs and over-the-counter(OTC)drugs were analyzed and new conceptions in pharmaceutical marketing such as the development and application of the service marketing were introduced as well.RESULTS&CONCLUSION:Di?versity,standardization,materialization are the right way the pharmaceutical enterprises should follow in the prescription drugs services;however,standardization,mechanics,brands are necessary for the OTC drugs services.