Objective To understand the infectious characteristics of a hamster-adapted scrapie strain 263K with five different routes of infection including intracerebral (i.e.), intraperitoneal (i.p.), intragastrical (i.g.), in...Objective To understand the infectious characteristics of a hamster-adapted scrapie strain 263K with five different routes of infection including intracerebral (i.e.), intraperitoneal (i.p.), intragastrical (i.g.), intracardiac and intramuscular (i.m.) approaches. Methods Hamsters were infected with crude- or fine-prepared brain extracts. The neuropathological changes, PrPSc deposits, and patterns of PK-resistant PrP were analyzed by HE stain, immunohistochemistry (IHC) assay and Western blot. Reactive gliosis and neuron loss were evaluated by glial fibrillary acidic protein (GFAP) and neuron specific enolase (NSE) specific IHC. Results The animals inoculated in i.m. and Lp. ways with crude PrPSc extracts showed clinical signs at the average incubation of 69.212.8 and 65.5±3.9 days. Inoculation in i.c. and intracardiac ways with fine PrPSc extracts (0.00035 g) caused similar, but relative long incubation of around 90 days. Only one out of eight hamsters challenged in i.g way with low dosage (0.01 g) became ill after a much longer incubation (185 d), while all animals (4/4) with high dosage (0.04 g) developed clinical signs 105 days postinfection. The most remarkable spongiform degeneration and PrPSc deposits were found in brain stem among the five challenge groups generally. The number of GFAP-positive astrocytes increased distinctly in brain stems in all infection groups, while the number of NSE-positive cells decreased significantly in cerebrum, except i.c. group. The patterns of PK-resistant PrP in brains were basically identical among the five infection routes. Conclusion Typical TSE could be induced in hamsters by inoculating strain 263K in the five infection ways. The incubation periods in bioassays depend on infective dosage, administrating pathway and preparation of PrPSc. The neuropathological changes and PrPSc deposits seem to be related with regions and inoculating pathways.展开更多
Dissolved organic matter（DOM） of municipal solid waste（MSW） consists of minerals, water, ash and humic substances, and is known to enhance plant growth. In this study, inoculating microbes（Z J, MS） were used in ...Dissolved organic matter（DOM） of municipal solid waste（MSW） consists of minerals, water, ash and humic substances, and is known to enhance plant growth. In this study, inoculating microbes（Z J, MS） were used in municipal solid wastes composting, and composting implemented a industrialized technology. During composting, dissolved organic matter was extracted from the compost and purified. The spectral characteristics of dissolved organic matter was determined by fluorescence emission, excitation, and synchronous spectroscopy. Fluorescence emission, excitation, and synchronous spectra characterized by different relative fluorescent intensities and peaks over time. Fluorescence spectra were similar to that of fulvic acid in sewage sludge, indicating the presence of dissolved organic matter with aromatic structures and a high degree of molecular polymerization. Compared with the controls with no microbial inoculation, the microbe-inoculated treatments exhibited the increase of aromatic polycondensation, in the following order： MS ＋ ZJ 〉 ZJ 〉 MS 〉 CK.展开更多
通过调整高速钢成分和采用RE K Na复合变质处理,改变了共晶碳化物的形态和分布,使铸造高速钢冲击韧度提高69 9%,热疲劳抗力也明显改善。变质处理高速钢导辊使用中不粘钢、不破碎、不剥落,使用寿命比高镍铬合金铸钢和Cr12MoV锻钢导辊提高...通过调整高速钢成分和采用RE K Na复合变质处理,改变了共晶碳化物的形态和分布,使铸造高速钢冲击韧度提高69 9%,热疲劳抗力也明显改善。变质处理高速钢导辊使用中不粘钢、不破碎、不剥落,使用寿命比高镍铬合金铸钢和Cr12MoV锻钢导辊提高2～3倍。展开更多
Ⅰ. INTRODUCTIONObtaining new kinds of high-T_c superconductors from Bi-Sr-Ca-Cu-O system has been an important objective of much research because of their containing no rare and noble metal. Superconductivity at 108 ...Ⅰ. INTRODUCTIONObtaining new kinds of high-T_c superconductors from Bi-Sr-Ca-Cu-O system has been an important objective of much research because of their containing no rare and noble metal. Superconductivity at 108 K can be obtained easily as 0.35 mol Pb (in nominal composition) is used to replace part of Bi in the system. Superconductivity at 118 K can be ob-展开更多
Background： Human Cytomegalovirus（HCMV） infections can be found throughout the body, especially in epithelial tissue. Animal model was established by inoculation of HCMV（strain AD-169） or coinoculation with Hepat...Background： Human Cytomegalovirus（HCMV） infections can be found throughout the body, especially in epithelial tissue. Animal model was established by inoculation of HCMV（strain AD-169） or coinoculation with Hepatitis E virus（HEV） into the ligated sacculus rotundus and vermiform appendix in living rabbits. The specimens were collected from animals sacrificed 1 and a half hours after infection.Results： The virus was found to be capable of reproducing in these specimens through RT-PCR and Western-blot.Severe inflammation damage was found in HCMV-infected tissue. The viral protein could be detected in high amounts in the mucosal epithelium and lamina propria by immunohistochemistry and immunofluorescense.Moreover, there are strong positive signals in lymphocytes, macrophages, and lymphoid follicles. Quantitative statistics indicate that lymphocytes among epithlium cells increased significantly in viral infection groups.Conclusions： The results showed that HCMV or HEV ＋ HCMV can efficiently infect in rabbits by vivo ligated intestine loop inoculation. The present study successfully developed an infective model in vivo rabbit ligated intestinal Loop for HCMV pathogenesis study. This rabbit model can be helpful for understanding modulation of the gut immune system with HCMV infection.展开更多
The paper reports the deposition（by magnetron sputtering） and properties of polycrystalline boron nitride （BN） layers on commercial inoculating alloy wires. As is characterized by means of Fourier transform infra...The paper reports the deposition（by magnetron sputtering） and properties of polycrystalline boron nitride （BN） layers on commercial inoculating alloy wires. As is characterized by means of Fourier transform infrared（FTIR） spectroscopy, electron energy dispersive X-ray（EDX） spectroscopy and scanning electron microscopy（SEM）, the thin BN layers consist of hexagonal and orthorhombic BN phases and are smooth without cracks. Organism transfer- ring-circles experiments reveal that the adhesion between the BN layer and alloy wire is very good after tens of cycles. It is demonstrated that the BN layers covered wires are biomaterial lubricious and self-cleaning. As a result, BN layer would effectively enhance the function and efficiency of inoculating alloy wires, which could be widely ap- plied to bio-experimentation and biomedicine apparatuses.展开更多
基金This work was supported by Chinese National Natural Science Foundation Grants 39928018,30070038 and 30130070, National High-tech Development Project (863 Project) 2001AA215391EU Project QLRT 2000 01441.
文摘Objective To understand the infectious characteristics of a hamster-adapted scrapie strain 263K with five different routes of infection including intracerebral (i.e.), intraperitoneal (i.p.), intragastrical (i.g.), intracardiac and intramuscular (i.m.) approaches. Methods Hamsters were infected with crude- or fine-prepared brain extracts. The neuropathological changes, PrPSc deposits, and patterns of PK-resistant PrP were analyzed by HE stain, immunohistochemistry (IHC) assay and Western blot. Reactive gliosis and neuron loss were evaluated by glial fibrillary acidic protein (GFAP) and neuron specific enolase (NSE) specific IHC. Results The animals inoculated in i.m. and Lp. ways with crude PrPSc extracts showed clinical signs at the average incubation of 69.212.8 and 65.5±3.9 days. Inoculation in i.c. and intracardiac ways with fine PrPSc extracts (0.00035 g) caused similar, but relative long incubation of around 90 days. Only one out of eight hamsters challenged in i.g way with low dosage (0.01 g) became ill after a much longer incubation (185 d), while all animals (4/4) with high dosage (0.04 g) developed clinical signs 105 days postinfection. The most remarkable spongiform degeneration and PrPSc deposits were found in brain stem among the five challenge groups generally. The number of GFAP-positive astrocytes increased distinctly in brain stems in all infection groups, while the number of NSE-positive cells decreased significantly in cerebrum, except i.c. group. The patterns of PK-resistant PrP in brains were basically identical among the five infection routes. Conclusion Typical TSE could be induced in hamsters by inoculating strain 263K in the five infection ways. The incubation periods in bioassays depend on infective dosage, administrating pathway and preparation of PrPSc. The neuropathological changes and PrPSc deposits seem to be related with regions and inoculating pathways.
文摘Dissolved organic matter（DOM） of municipal solid waste（MSW） consists of minerals, water, ash and humic substances, and is known to enhance plant growth. In this study, inoculating microbes（Z J, MS） were used in municipal solid wastes composting, and composting implemented a industrialized technology. During composting, dissolved organic matter was extracted from the compost and purified. The spectral characteristics of dissolved organic matter was determined by fluorescence emission, excitation, and synchronous spectroscopy. Fluorescence emission, excitation, and synchronous spectra characterized by different relative fluorescent intensities and peaks over time. Fluorescence spectra were similar to that of fulvic acid in sewage sludge, indicating the presence of dissolved organic matter with aromatic structures and a high degree of molecular polymerization. Compared with the controls with no microbial inoculation, the microbe-inoculated treatments exhibited the increase of aromatic polycondensation, in the following order： MS ＋ ZJ 〉 ZJ 〉 MS 〉 CK.
文摘Ⅰ. INTRODUCTIONObtaining new kinds of high-T_c superconductors from Bi-Sr-Ca-Cu-O system has been an important objective of much research because of their containing no rare and noble metal. Superconductivity at 108 K can be obtained easily as 0.35 mol Pb (in nominal composition) is used to replace part of Bi in the system. Superconductivity at 118 K can be ob-
基金supported by the National Natural Science Foundation of China(31272515,31472165,31330076)
文摘Background： Human Cytomegalovirus（HCMV） infections can be found throughout the body, especially in epithelial tissue. Animal model was established by inoculation of HCMV（strain AD-169） or coinoculation with Hepatitis E virus（HEV） into the ligated sacculus rotundus and vermiform appendix in living rabbits. The specimens were collected from animals sacrificed 1 and a half hours after infection.Results： The virus was found to be capable of reproducing in these specimens through RT-PCR and Western-blot.Severe inflammation damage was found in HCMV-infected tissue. The viral protein could be detected in high amounts in the mucosal epithelium and lamina propria by immunohistochemistry and immunofluorescense.Moreover, there are strong positive signals in lymphocytes, macrophages, and lymphoid follicles. Quantitative statistics indicate that lymphocytes among epithlium cells increased significantly in viral infection groups.Conclusions： The results showed that HCMV or HEV ＋ HCMV can efficiently infect in rabbits by vivo ligated intestine loop inoculation. The present study successfully developed an infective model in vivo rabbit ligated intestinal Loop for HCMV pathogenesis study. This rabbit model can be helpful for understanding modulation of the gut immune system with HCMV infection.
基金Supported by the National Natural Science Foundation of China（Nos.51072066, 50772041）, the Specialized Research Fund for the Doctoral Program of Higher Education of China（No.20100061110083） and the New Century Excellent Talents in Univer- sities of China（No.NCET-06-0303）.
文摘The paper reports the deposition（by magnetron sputtering） and properties of polycrystalline boron nitride （BN） layers on commercial inoculating alloy wires. As is characterized by means of Fourier transform infrared（FTIR） spectroscopy, electron energy dispersive X-ray（EDX） spectroscopy and scanning electron microscopy（SEM）, the thin BN layers consist of hexagonal and orthorhombic BN phases and are smooth without cracks. Organism transfer- ring-circles experiments reveal that the adhesion between the BN layer and alloy wire is very good after tens of cycles. It is demonstrated that the BN layers covered wires are biomaterial lubricious and self-cleaning. As a result, BN layer would effectively enhance the function and efficiency of inoculating alloy wires, which could be widely ap- plied to bio-experimentation and biomedicine apparatuses.
