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91.
Genome of the European elk papillomavirus (EEPV)   总被引:1,自引:0,他引:1  
The genome of the European elk papillomavirus (EEPV) was found to be 8,095 base pairs (bp) long and its genetic organization was similar to that of other papillomaviruses. Ten open reading frames (ORFs), designated E1-E7 and L1-L3, were identified in the genome, all located on one strand. The presence of the L3 ORF is rare among the papillomaviruses and to date has only been identified in the genomes of EEPV, the deer papillomavirus (DPV) and the Cottontail papillomavirus (CRPV). The ORF is well conserved beteeen DPV and EEPV with regard to both length and sequence. Potential promoter regions were identified at the 5-end of the E6 ORF, at the 3-end of the E1 ORF and downstream of the L1 ORF. Furthermore, two potential polyadenylation signals were found, one located in the long control region (LCR), downstream of the L1 ORF, and another preceding the L2 ORF. The EEVP genome is closely related to the genome of the DPV, the most highly conserved regions being ORFs E1 (70%), E5 (69%), and L1 (74%).  相似文献   
92.
We undertook a theoretical analysis of the source resistance of the left ventricle represented in a mean pressure-mean flow diagram, using the chamber properties established in terms of the pressure-volume relationship. This analysis showed that pairs of points should lie above the linear function proposed by Elzinga and Westerhof. A third-order polynomial function would theoretically explain better than a linear relation or a parabolic fit the curved shape of experimentally obtained relationships. The analysis resolves the discrepancy between Elzinga and Westerhof's theoretical concept of linear source resistance and the actual nonlinear relationship.  相似文献   
93.
The induction of class I HLA expression by interferon-α (IFN-α) was studied in lymphoid cells arrested or traversing different stages of the cell cycle. Exponential cultures of MOLT-4 cells and the MOLT-4 cell variant YHHH were treated with the cell cycle inhibitors aphidicolin and colcemid to obtain cell populations arrested in G1/S and G2/M, respectively, and also cells traversing from S to M and vice versa. Cytofluorimetry with the monoclonal antibody YTH/76.3 (which specifically detects those class I molecules which are most susceptible to IFN-α induction) was used to quantitate the class I HLA response to IFN-α. The results showed that the response to IFN-α is not restricted to a given stage of the cell cycle. These studies also revealed that when the cells were arrested at G1/S, the absolute level of class I HLA expression was enhanced 2–3-fold, both in the presence or absence of either IFN-α or IFN-γ. Therefore, even when absolute levels changed, the ratio of IFN-induced expression to basal expression remained constant at all cell cycle stages. The level of expression of another surface antigen (the CD1 antigen HTA-1) was not affected by the G1/S block. The results were confirmed by dot blot hybridization of poly (A)+ RNA using cDNA-specific probes. These findings suggest that the effect of IFN-α is continuous throughout the cell cycle but that a G1-dependent event determines the extent of class I HLA expression, and leads to a synergistic superinduction by IFN in G1/S-arrested cells.  相似文献   
94.
Imaging by scanning electron microscopy (SEM) can provide insight into viral egress. At a low magnification level, varicella zoster virions (VZV) emerge from an infected cell surface in a distinctive pattern previously described as "viral highways." Viral highways consist of thousands of particles arranged in linear pathways across the syncytial surface. This egress pattern has not been described with other herpesviruses, but a systematic analysis has not been performed. Therefore, the characteristic arrangement of VZV egress was compared with that of six other members of the herpes virus family, including herpes simplex virus (HSV) types 1 and 2, human cytomegalovirus (CMV), pseudorabies virus (PRV), and human herpesvirus types 6 and 7 (HHV-6 and HHV-7). Only VZV-infected cells exhibited viral highways. Subsequent SEM examination of VZ virions at an ultra high-resolution revealed that more than 70% were aberrant. Further imaging of the other herpesviruses demonstrated that VZV structure was more closely related to PRV than HSV-1 or HSV-2. Finally, it is noted that the individual members of the herpesvirus family have distinguishable SEM profiles.  相似文献   
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Using a spectrophotometric NBT reduction assay and phagocytosis, we identified that production of superoxide anions and phagocytic activity of hemocytes from Macrobrachium rosenbergii were significantly higher in the presence of rat, rabbit, and chicken erythrocytes than with human, pig, or horse erythrocytes. Hemocytes stimulated with MrL, MrLMab, or PMA increased 4.7, 5.1, and 6.1 fold, respectively, the oxidative response as compared to non-stimulated hemocytes. MrLMab together with MrL increased 5.7 fold the oxidative capacity of hemocytes as compared to non-stimulated cells. These effects were inhibited with 100 mM GalNAc, GlcNAc, or Neu5Ac and 0.2 microM of sialylated submaxillary gland mucin and fetuin. Piroxicam inhibited (P < 0.05) the production of O(2)(-) induced by MrL, whereas iodoacetamide inhibited the effect of MrLMAb (P < 0.05) in a dose-dependent manner. Our results suggest that MrLMab might activate the oxidative burst through the metabolism of glucose as opposed to MrL which utilizes NADPH-independent mechanisms, very probably through pro-inflammatory metabolites.  相似文献   
97.
Co-infection by human immunodeficiency virus and hepatitis B and C viruses is quite common because they share similar routes of transmission. The introduction of highly active antiretroviral therapy has significantly improved the life expectancy of HIV-infected patients in the last few years. However, chronic viral hepatitis represents an emerging cause of morbidity and mortality in this population, either as a result of end-stage liver disease or as a consequence of hepatotoxicity induced by antiretroviral drugs. The main goal of the Consensus Conference was to establish specific recommendations for the management of chronic viral hepatitis B and C in HIV-infected patients. The role of orthotopic liver transplantation for co-infected individuals with end-stage liver disease was also assessed.  相似文献   
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Typhoid fever remains a serious public health problem. We have developed a vaccine from Salmonella enterica serovar typhi (S. typhi) outer-membrane proteins (OMPs) known as porins. A single subcutaneous dose of 10 microg of porins induced a five-fold (P = 0.05) seroconversion index consisting of IgM and IgG at 7 and 15 days after vaccination as well as the production of IgG1 and IgG2 isotypes. The porins-based vaccine induced a two-fold increase (P = 0.05) in bactericidal titres in volunteers, whom also developed a T-cell response characterized by the production of interferon-gamma (INF-gamma). Side effects after vaccination were mild and transient. The data showed that our S. typhi porins-based candidate vaccine is safe and immunogenic in healthy humans.  相似文献   
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