Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.3.1.177 (BIS)
 957 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A study on the composition of the resin component of the several brands of composite resin has not been published so far. It was the purpose of the present work to fill out this gap in our knowledge of this important group of restorative materials by analyzing the monomers of the materials as delivered by the manufacturers. 24 brands of restorative resins were investigated by means of a Nuclear Magnetic Resonance spectrometer at 90 MHz. Spectra were taken of deuterated chloroform solutions of the organic part of the filling materials and compared with spectra of pure monomers that were conceivable constituents of the investigated brands. It was found that the BIS-GMA containing brands all contain at least one other monomer, most often TEDMA, in varying concentrations. The brands with MMA as main component in most cases also contain other monomers.
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PMID:NMR-analysis of monomers in restorative resins. 106 16

Cell culture techniques were used to determine the source of cytotoxic agents in a commercial BIS-GMA composite. The material was polymerized according to the manufacturer's directions and leachable components were removed by room temperature extraction in ethanol, chloroform, or toluene. The leachable components in the extracts were identified using infrared spectrographic analysis. Thin layer chromatographic analysis was used to determine the number of constituents. These constituents were separated by gas chromatography and then identified by mass spectrographic analysis. Succinic dehydrogenase activity and radioactive labeling with tritiated leucine were used to evaluate cell metabolism and protein synthesis, respectively. The infrared analysis of the extracts showed that the primary component was unreacted BIS-GMA. Trace amounts of 2-hydroxy-4-methoxy-benzophenone, a light stabilizer, as well as a phenyl ester of benzoic acid which was probably degraded from BIS-GMA, were detected by the mass spectrographic method. The removal of leachable components caused a 90% decrease in toxicity compared to the nonextracted BIS-GMA samples. The extracted BIS-GMA samples showed no cellular response compared to the Teflon negative control.
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PMID:Cytotoxicity of a BIS-GMA dental composite before and after leaching in organic solvents. 182 7