The two most important criteria for dental materials are their biofunctional and biocompatible endurance within the anticipated life-span of the dental restoration in the mouth. Biocompatibility relates mainly to the ...The two most important criteria for dental materials are their biofunctional and biocompatible endurance within the anticipated life-span of the dental restoration in the mouth. Biocompatibility relates mainly to the allergenicity and the toxicity of the material. To test the non-specific toxicity of dental materials, in vitro cell culture assays have been developed. For in vitro screening, such tests are recommended to check the cytotoxicity of dental materials (ISO 10993 5). Various studies have already been performed to quantitatively determine the cytotoxicity level of dental alloys. However, as long as only dental alloys and the cell culture technique are applied, it is not possible to determine which of the alloying elements cause the cytotoxicity. Therefore, an analytical method is needed. Wataha et al determined in 1991 the TC50 values of 9 metal cations of various dental casting alloys, using cell culture methods. Kapert et al reported in 1994 a complex in vitro test concept, where the ICP analysis (inductively coupled plasma emission spectroscopy) was introduced to measure the trace elements extracted from various alloys. Experimentelle Zahnheilkunde, Universitts ZMK Klinik Freiburg, Germany (Lü XY and Kappert HF) The aim of the present study was to find a relation between the ICP results, the TC50 value of metal cations, and the cytotoxicity of dental alloys. The cytotoxicity levels of various dental alloys and the TC50 values of 10 metal cations were established using the MTT assay, an effective cell culture of method. Then, the concentrations of the corrosively soluted metal cations in the extracts of the alloys were measured using the ICP method. From all these experimental results it was found that the relation between the effective cytotoxicity Z eff of an alloy, the concentrations C i of i th trace element and the TC50 values T Ci of the i th metal cation can approximately be expressed by Z eff =∑iC i2·T Ci . Two significant applications of this expression are a) The cytotoxicity of an alloy can be estimated by ICP analysis of the extract if the TC50 values of the trace elements are know. b) The cytotoxicity of a new-developed-alloy can be estimated in advance, according to the alloying components.展开更多
Jiaozi Steamed Bread(JSB)has a unique aroma as a traditional staple food in China.The volatile compounds in JSBwere extracted by simultaneous distillation and extraction(SDE)and headspace solid-phasemicroextraction(HS...Jiaozi Steamed Bread(JSB)has a unique aroma as a traditional staple food in China.The volatile compounds in JSBwere extracted by simultaneous distillation and extraction(SDE)and headspace solid-phasemicroextraction(HS-SPME).These volatile substances were analyzed by gas chromatography-mass spectrometry(GC-MS)and gas chromatographyolfactometry-mass spectrometry(GC-O-MS).The results demonstrated that 61 volatile compounds were identified totally in samples,of which 15 were confirmed as potent aroma compounds with odor active values(OAVs)>1.The 15 potent aroma compounds were ethanol,1-butanol,1-pentanol,1-hexanol,heptanol,1-octen-3-ol,3-methyl-1-butanol,hexanal,heptanal,nonanal,(E)-2-heptenal,benzaldehyde,(E,E)-2,4-decadienal,2-pentylfuran and naphthalene.The SDEmethod had better linearity with coefficients of determination(R2)equal to or higher than 0.9991.Furthermore,the SDE method also achieved lower sensitivity and better repeatability and recovery than HS-SPME.This work provides reference method and parameters for future research on the flavor of JSB for commercial products.展开更多
文摘The two most important criteria for dental materials are their biofunctional and biocompatible endurance within the anticipated life-span of the dental restoration in the mouth. Biocompatibility relates mainly to the allergenicity and the toxicity of the material. To test the non-specific toxicity of dental materials, in vitro cell culture assays have been developed. For in vitro screening, such tests are recommended to check the cytotoxicity of dental materials (ISO 10993 5). Various studies have already been performed to quantitatively determine the cytotoxicity level of dental alloys. However, as long as only dental alloys and the cell culture technique are applied, it is not possible to determine which of the alloying elements cause the cytotoxicity. Therefore, an analytical method is needed. Wataha et al determined in 1991 the TC50 values of 9 metal cations of various dental casting alloys, using cell culture methods. Kapert et al reported in 1994 a complex in vitro test concept, where the ICP analysis (inductively coupled plasma emission spectroscopy) was introduced to measure the trace elements extracted from various alloys. Experimentelle Zahnheilkunde, Universitts ZMK Klinik Freiburg, Germany (Lü XY and Kappert HF) The aim of the present study was to find a relation between the ICP results, the TC50 value of metal cations, and the cytotoxicity of dental alloys. The cytotoxicity levels of various dental alloys and the TC50 values of 10 metal cations were established using the MTT assay, an effective cell culture of method. Then, the concentrations of the corrosively soluted metal cations in the extracts of the alloys were measured using the ICP method. From all these experimental results it was found that the relation between the effective cytotoxicity Z eff of an alloy, the concentrations C i of i th trace element and the TC50 values T Ci of the i th metal cation can approximately be expressed by Z eff =∑iC i2·T Ci . Two significant applications of this expression are a) The cytotoxicity of an alloy can be estimated by ICP analysis of the extract if the TC50 values of the trace elements are know. b) The cytotoxicity of a new-developed-alloy can be estimated in advance, according to the alloying components.
基金This project was supported by the National Natural Science Foundation of China(No.31701635)the Key Laboratory of Staple Grain Processing,Ministry of Agriculture(No.DZLS201703)the Henan University of Technology High-level Talents Fund(No.2015BS009).
文摘Jiaozi Steamed Bread(JSB)has a unique aroma as a traditional staple food in China.The volatile compounds in JSBwere extracted by simultaneous distillation and extraction(SDE)and headspace solid-phasemicroextraction(HS-SPME).These volatile substances were analyzed by gas chromatography-mass spectrometry(GC-MS)and gas chromatographyolfactometry-mass spectrometry(GC-O-MS).The results demonstrated that 61 volatile compounds were identified totally in samples,of which 15 were confirmed as potent aroma compounds with odor active values(OAVs)>1.The 15 potent aroma compounds were ethanol,1-butanol,1-pentanol,1-hexanol,heptanol,1-octen-3-ol,3-methyl-1-butanol,hexanal,heptanal,nonanal,(E)-2-heptenal,benzaldehyde,(E,E)-2,4-decadienal,2-pentylfuran and naphthalene.The SDEmethod had better linearity with coefficients of determination(R2)equal to or higher than 0.9991.Furthermore,the SDE method also achieved lower sensitivity and better repeatability and recovery than HS-SPME.This work provides reference method and parameters for future research on the flavor of JSB for commercial products.
