1.Study on MR Imaging of Gliomas Treated by Gamma Knife( An Analysis of 106 Cases )
Yihong GUO ; Xibiao WU ; Yong HE
Journal of Practical Radiology 2001;0(05):-
Objective To evaluate the effectiveness of gamma knife and radioactive effect for glioma.Methods MR images of 106 cases with glioma treated by gamma knife were analysed based on classified.Results The effectiveness of gamma knife was the best for ependyoma and oligodendroglioma,the secondly for astocytoma (Ⅰ~Ⅱ) .The effectiveness for astrocytoma( Ⅲ~Ⅳ)was not well.The effective rate in 1 year after treament for astocytoma(Ⅰ~Ⅱ)was far higher than 2~3 years later.The 2nd year after treatment was the peak time for edema around tumor and the special radioactive contrast enhancement on MR.Conclusion Gamma knife is a effective therapy for glioma,especially for ependyoma,oligodendroglioma and astocytoma(Ⅰ~Ⅱ).The radioactive effect showed as edema and radioactive contrast enhancement on MR can become smaller or disappear 2 years later after treament.
2.Characterization of attenuated Salmonella C500 strain with a delta asd mutant and use as an Asd+ balanced-lethal host-vector system.
Zhanqin ZHAO ; Yindi XU ; Bin WU ; Xiangchao CHENG ; Yinju LI ; Xibiao TANG ; Chunjie ZHANG ; Huanchun CHEN
Chinese Journal of Biotechnology 2009;25(1):29-36
Salmonella enterica serovar Choleraesuis strain C500 is a live, attenuated vaccine that has been used in China for over 40 years to prevent piglet paratyphoid. The objective of this study was to evaluate the potential of attenuated Salmonella enterica serovar Choleraesuis C500 strain with a delta asd mutant as an effective live vaccine vector by the Asd+ balanced-lethal host-vector system. Here, we compared the characteristics of S. enterica serovar Choleraesuis delta asdC500 strain with the parent C500 strain, including phenotype, growth rate, virulence, safety, and expression for heterologous antigen. The mean generation times of delta asdC500 mutant, the vector control delta asdC500 (pYA3493), and the parent avirulent C500 vaccine strain in Luria broth were 30.7, 28.1, and 27.9 min, respectively. The fermentation patterns of theses three strains on different carbohydrates, and the levels of production of H2S, were similar. The O and H antigens of delta asdC500 mutant, delta asdC500 (pYA3493) and delta asdC500 (pYA-F1P2) were 6,7:C:1,5, identical to the parent strain C500. By the method of Reed and Muench, groups of mice were challenged by the intraperitoneal route with different amounts of delta asdC500 (pYA3493) or the parent C500 strain, and the virulence of delta asdC500 (pYA3493) with LD50 of 1.1 x 10(7) CFU was a little lower than C500 with LD50 of 4.4 x 10(6) CFU. All piglets inoculated with delta asdC500 (pYA3493) or C500 survived, and no signs of disease were observed during the entire experimental period. No major differences were found in these two groups. In addition, the recombinant pYA-F1P2 plasmid was very stable in the recombinant delta asdC500 (pYA-F1P2) strain, which expressed secretorily a large amount of the recombinant filamentous hemagglutinin type I domain and pertactin region 2 domain antigen (rF1P2) of Bordetella bronchiseptica. In this study, we have shown that the delta asdC500 mutant had a series of biological characteristics similar to the parent vaccine strain C500. Furthermore, the strain could express secretorily a large amount of heterologous antigen. It is likely that this Salmonella expression and delivery system could be easily adapted to develop multivalent recombinant Salmonella vaccines against infectious agents using the Asd+ balanced-lethal host-vector system.
Amino Acid Oxidoreductases
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genetics
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Animals
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Bacterial Proteins
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genetics
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Gene Deletion
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Genetic Vectors
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Mice
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Mutation
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Salmonella Vaccines
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genetics
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immunology
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Salmonella enterica
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genetics
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immunology
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pathogenicity
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Swine
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Transduction, Genetic
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Vaccines, Attenuated
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genetics
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immunology
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Vaccines, Synthetic
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genetics
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immunology
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Virulence