Objective To expatiate dynamic changes in hamsters infected with scrapie strain 263K,to observe the presence and aggravation of various forms of PrP and PrP^sc during incubation period,and to probe primarily the relat...Objective To expatiate dynamic changes in hamsters infected with scrapie strain 263K,to observe the presence and aggravation of various forms of PrP and PrP^sc during incubation period,and to probe primarily the relationship between the onset of clinic manifestations and the presence of different PrP^sc forms. Methods Hamster-adapted scrapie strain 263K was intracerebrally inoculated into hamsters. Different forms of PrP and PrP^sc were monitored dynamically by Western blot and immuno-histochemical assays. The presence of scrapie-associated fibril (SAF) was assayed by election microscopy analysis (EM) and immuno-golden EM.Results PrP^sc was initially detected in the brain tissues of the animals in 20 days post-inoculation by immunohistochemistry and 40 days with Western blot. Quantitative evaluations revealed that the amounts of PrP and PrP^sc in brain tissues increased along with the incubation.Several high and low molecular masses of PrP were seen in the brains of the long-life span infected animals. Deglycosylation assays identified that the truncated PrP in the infected brains showed similar glycosylation patterns as the full-length PrP. The presence of short fragments was seemed to relate with the onset of clinical conditions. Conclusion These results indicate that infectious agents exist and accumulate in central nerve system prior to the onset of the illness. Various molecular patterns of PrPs~ may indwell in brain tissues during the infection.展开更多
AIM: To investigate the putative role of human papillomavirus (HPV) infection in the carcinogenesis of esophageal squamous cell carcinoma in China.METHODS: Twenty-three esophageal squamous cell carcinoma samples and t...AIM: To investigate the putative role of human papillomavirus (HPV) infection in the carcinogenesis of esophageal squamous cell carcinoma in China.METHODS: Twenty-three esophageal squamous cell carcinoma samples and the distal normal epithelium from Shanxi Province, and 25 more esophageal squamous cell carcinoma samples from Anyang city, two areas with a high incidence of esophageal cancer in China, were detected for the existence of HPV-16 DNA by PCR, mRNA in situ hybridization (ISH) and immunohistochemistry (IHC) targeting HPV-16 E6 gene.
RESULTS: There were approximately 64 % (31/48) patients having HPV-16 DNA in tumor samples, among them nearly twothirds (19/31) samples were detected with mRNA expression of HPV-16 E6. However, in the normal esophageal epithelium from cancer patients, the DNA and mRNA of HPV-16 were found with much less rate: 34.7 % (8/23) and 26.1% (6/23) respectively.In addition, at protein level detected by IHC assay, 27.1% (13/48) tumor samples had virus oncoprotein E6 expression, while only one case of normal epithelium was found positive.CONCLUSION: HPV infection, especially type 16, should be considered as a risk factor for esophageal malignancies in China.展开更多
基金This work was supported by the National Natural Science Foundation of China, No. 39928018, 30070038 and 30130070, National High-tech Research Development Program (863 Program), No. 2001AA215391, and EU Project QLRT, No. 200001441.
文摘Objective To expatiate dynamic changes in hamsters infected with scrapie strain 263K,to observe the presence and aggravation of various forms of PrP and PrP^sc during incubation period,and to probe primarily the relationship between the onset of clinic manifestations and the presence of different PrP^sc forms. Methods Hamster-adapted scrapie strain 263K was intracerebrally inoculated into hamsters. Different forms of PrP and PrP^sc were monitored dynamically by Western blot and immuno-histochemical assays. The presence of scrapie-associated fibril (SAF) was assayed by election microscopy analysis (EM) and immuno-golden EM.Results PrP^sc was initially detected in the brain tissues of the animals in 20 days post-inoculation by immunohistochemistry and 40 days with Western blot. Quantitative evaluations revealed that the amounts of PrP and PrP^sc in brain tissues increased along with the incubation.Several high and low molecular masses of PrP were seen in the brains of the long-life span infected animals. Deglycosylation assays identified that the truncated PrP in the infected brains showed similar glycosylation patterns as the full-length PrP. The presence of short fragments was seemed to relate with the onset of clinical conditions. Conclusion These results indicate that infectious agents exist and accumulate in central nerve system prior to the onset of the illness. Various molecular patterns of PrPs~ may indwell in brain tissues during the infection.
基金grants from the National Natural Science Foundation of China,No.39925020State Key Basic Research Program,No.G 1998051204
文摘AIM: To investigate the putative role of human papillomavirus (HPV) infection in the carcinogenesis of esophageal squamous cell carcinoma in China.METHODS: Twenty-three esophageal squamous cell carcinoma samples and the distal normal epithelium from Shanxi Province, and 25 more esophageal squamous cell carcinoma samples from Anyang city, two areas with a high incidence of esophageal cancer in China, were detected for the existence of HPV-16 DNA by PCR, mRNA in situ hybridization (ISH) and immunohistochemistry (IHC) targeting HPV-16 E6 gene.
RESULTS: There were approximately 64 % (31/48) patients having HPV-16 DNA in tumor samples, among them nearly twothirds (19/31) samples were detected with mRNA expression of HPV-16 E6. However, in the normal esophageal epithelium from cancer patients, the DNA and mRNA of HPV-16 were found with much less rate: 34.7 % (8/23) and 26.1% (6/23) respectively.In addition, at protein level detected by IHC assay, 27.1% (13/48) tumor samples had virus oncoprotein E6 expression, while only one case of normal epithelium was found positive.CONCLUSION: HPV infection, especially type 16, should be considered as a risk factor for esophageal malignancies in China.