Our previous studies have shown that zein has good biocompatibility and good mechanical properties. The first product from a porous scaffold of zein, a resorbable bone substitute, has passed the biological evaluation ...Our previous studies have shown that zein has good biocompatibility and good mechanical properties. The first product from a porous scaffold of zein, a resorbable bone substitute, has passed the biological evaluation of medical devices （ISO 10993） by the China Food and Drug Administration. However, Class III medical devices need quality monitoring before being placed on the market, and such monitoring includes quality control of raw materials, choice of sterilization method, and evaluation of biocompatibility. In this paper, we investigated four sources of zein through amino acid analysis （AAA） and sodium dodecyl sulfate polyacrylamide gel electrophoresis （SDS-PAGE） in order to monitor the composition and purity, and control the quality of raw materials. We studied the effect of three kinds of sterilization method on a porous zein scaffold by SDS-PAGE. We also compared the changes in SDS-PAGE patterns when irradiated with different doses of gamma radiation. We found that polymerization or breakage did not occur on peptide chains of zein during gamma-ray （y-ray） sterilization in the range of 20-30 kGy, which suggested that γ-ray sterilization is suitable for porous zein scaffolds, Regarding cell compatibility, we found a difference between using a 3-（4,5-dimethylthiazol-2-yl）-2,5-diphenyl tetrazolium bromide （MTT） assay and a cell-counting kit-8 （CCK-8） assay to assess cell proliferation on zein film, and concluded that the CCK-8 assay is more suitable, due to its low background optical density.展开更多
Effects of 60Co-γ ray radicidation on instant tea were studied through contaminant microbe assay,absorbed dose measurement and analysis of principal components of instant tea.The minimum effective dose of 4.0kGy and ...Effects of 60Co-γ ray radicidation on instant tea were studied through contaminant microbe assay,absorbed dose measurement and analysis of principal components of instant tea.The minimum effective dose of 4.0kGy and maximum tolerance dose of 8.0KGy were proposed.展开更多
Objective： To analyze the clinical outcomes of arthroscopic anterior cruciate ligament （ACL） reconstruction with irradiated bone-patellar tendon-bone （BPTB） allograft compared with non-irradiated allograft and au...Objective： To analyze the clinical outcomes of arthroscopic anterior cruciate ligament （ACL） reconstruction with irradiated bone-patellar tendon-bone （BPTB） allograft compared with non-irradiated allograft and autograft. Methods： All BPTB allografts were obtained from a single tissue bank and the irradiated allografts were sterilized with 2.5 mrad of irradiation prior to distribution. A total of 68 patients undergoing arthroscopic ACL reconstruction were prospectively randomized consecutively into one of the two groups （autograft and irradiated allograft groups）. The same surgical technique was used in all operations done by the same senior surgeon. Before surgery and at the average of 31 months of follow-up （ranging from 24 to 47 months）, patients were evaluated by the same observer according to objective and subjective clinical evaluations. Results： Of these patients, 65 （autograft 33, irradiated allograft 32） were available for full evaluation. When the irradiated allografl group was compared to the autograft group at the 31 -month follow-up by the Lachman test, the anterior drawer test （ADT）, the pivot shift test, and KT-2000 arthrometer test, statistically significant differences were found. Most importantly, 87.8% of patients in the autograft group and just only 31.3% in the irradiated allograft group had a side-to-side difference of less than 3 mm according to KT-2000. The failure rate of the ACL reconstruction with irradiated allograft （34.4%） was higher than that with autograft （6.1%）. The anterior and rotational stabilities decreased significantly in the irradiated allograft group. According to the overall International Knee Documentation Committee （1KDC）, functional and subjective evaluations, and activity level testing, no statistically significant differences were found between the two groups. Besides, patients in the irradiated allograft group had a shorter operation time and a longer duration of postoperative fever. When the patients had a fever, the laboratory examinations of all patients were almost normal. Blood routine was normal, the values of erythrocyte sedimentation rate （ESR） were 5-16 mm/h and the contents of C reactive protein （CRP） were 3-10 mg/L. Conclusion： We conclude that the short term clinical outcomes of the ACL reconstruction with irradiated BPTB allograft were adversely affected. The less than satisfactory results led the senior authors to discontinue the use of irradiated BPTB allografl in ACL surgery and not to advocate using the gamma irradiation as a secondary sterilizing method.展开更多
文摘Our previous studies have shown that zein has good biocompatibility and good mechanical properties. The first product from a porous scaffold of zein, a resorbable bone substitute, has passed the biological evaluation of medical devices （ISO 10993） by the China Food and Drug Administration. However, Class III medical devices need quality monitoring before being placed on the market, and such monitoring includes quality control of raw materials, choice of sterilization method, and evaluation of biocompatibility. In this paper, we investigated four sources of zein through amino acid analysis （AAA） and sodium dodecyl sulfate polyacrylamide gel electrophoresis （SDS-PAGE） in order to monitor the composition and purity, and control the quality of raw materials. We studied the effect of three kinds of sterilization method on a porous zein scaffold by SDS-PAGE. We also compared the changes in SDS-PAGE patterns when irradiated with different doses of gamma radiation. We found that polymerization or breakage did not occur on peptide chains of zein during gamma-ray （y-ray） sterilization in the range of 20-30 kGy, which suggested that γ-ray sterilization is suitable for porous zein scaffolds, Regarding cell compatibility, we found a difference between using a 3-（4,5-dimethylthiazol-2-yl）-2,5-diphenyl tetrazolium bromide （MTT） assay and a cell-counting kit-8 （CCK-8） assay to assess cell proliferation on zein film, and concluded that the CCK-8 assay is more suitable, due to its low background optical density.
文摘Effects of 60Co-γ ray radicidation on instant tea were studied through contaminant microbe assay,absorbed dose measurement and analysis of principal components of instant tea.The minimum effective dose of 4.0kGy and maximum tolerance dose of 8.0KGy were proposed.
基金Project (No. 2004GG2202034) supported by the Natural Science Foundation of Shandong Province, China
文摘Objective： To analyze the clinical outcomes of arthroscopic anterior cruciate ligament （ACL） reconstruction with irradiated bone-patellar tendon-bone （BPTB） allograft compared with non-irradiated allograft and autograft. Methods： All BPTB allografts were obtained from a single tissue bank and the irradiated allografts were sterilized with 2.5 mrad of irradiation prior to distribution. A total of 68 patients undergoing arthroscopic ACL reconstruction were prospectively randomized consecutively into one of the two groups （autograft and irradiated allograft groups）. The same surgical technique was used in all operations done by the same senior surgeon. Before surgery and at the average of 31 months of follow-up （ranging from 24 to 47 months）, patients were evaluated by the same observer according to objective and subjective clinical evaluations. Results： Of these patients, 65 （autograft 33, irradiated allograft 32） were available for full evaluation. When the irradiated allografl group was compared to the autograft group at the 31 -month follow-up by the Lachman test, the anterior drawer test （ADT）, the pivot shift test, and KT-2000 arthrometer test, statistically significant differences were found. Most importantly, 87.8% of patients in the autograft group and just only 31.3% in the irradiated allograft group had a side-to-side difference of less than 3 mm according to KT-2000. The failure rate of the ACL reconstruction with irradiated allograft （34.4%） was higher than that with autograft （6.1%）. The anterior and rotational stabilities decreased significantly in the irradiated allograft group. According to the overall International Knee Documentation Committee （1KDC）, functional and subjective evaluations, and activity level testing, no statistically significant differences were found between the two groups. Besides, patients in the irradiated allograft group had a shorter operation time and a longer duration of postoperative fever. When the patients had a fever, the laboratory examinations of all patients were almost normal. Blood routine was normal, the values of erythrocyte sedimentation rate （ESR） were 5-16 mm/h and the contents of C reactive protein （CRP） were 3-10 mg/L. Conclusion： We conclude that the short term clinical outcomes of the ACL reconstruction with irradiated BPTB allograft were adversely affected. The less than satisfactory results led the senior authors to discontinue the use of irradiated BPTB allografl in ACL surgery and not to advocate using the gamma irradiation as a secondary sterilizing method.
