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A 'minimal' approach in design of flavivirus infectious DNA.   总被引:4,自引:0,他引:4  
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Induction of Cytochrome P-4502E1 by Ethanol in Rat Kupffer Cells   总被引:1,自引:0,他引:1  
Ethanol has been shown to affect several Kupffer cell functions, but the mechanisms underlying these changes are unknown. One possible mediator is cytochrome P-4502E1 (CYP2E1), an ethanol-inducible enzyme that has been associated with toxic effects in the liver, as well as in many extrahepatic organs. To assess whether CYP2E1 can be induced by ethanol in Kupffer cells, male rats pair-fed ethanol-containing or control Lieber-DeCarli diets for 3 weeks were studied. Immunoblotting experiments showed that ethanol-treatment caused a 7-fold increase in CYP2E1 content both in Kupffer cells and hepatocytes. When expressed per milligram of S9 protein, the content of CYP2E1 in Kupffer cells was, however, 10 times lower than in hepatocytes. Immunohistochemical studies revealed that CYP2E1 is located in the endoplasmic reticulum of Kupffer cells in vivo and that it is also present in isolated Kupffer cells. In both Kupffer cells and hepatocytes, ethanol feeding increased the hydroxylation of p -nitrophenol, a relatively specific substrate for CYP2E1, demonstrating that the induced CYP2E1 was catalytically active. This reaction was significantly inhibited by anti-CYP2E1 IgG in both types of cells. Although CYP2E1 may not be the predominant pathway for ethanol metabolism in hepatocytes, it is possibly the major one in Kupffer cells. Thus, the induction of CYP2E1 by ethanol in these cells could cause significant changes in intracellular acetaldehyde concentrations which, together with increased lipid peroxidation, may contribute to the development of alcoholic liver injury.  相似文献   
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A murine monoclonal antibody made against an idiotypic determinant (Id) of surface IgM/IgD lambda molecules on chronic lymphocytic leukemia (CLL) cells of a 71-year-old woman was used for clonal analysis by two- color immunofluorescence. The anti-Id antibody identified IgM+/IgD+/lambda+ B cells as the predominant cell type of her CLL clone. In addition, substantial proportions of the IgG and IgA B cells and most of the IgM plasma cells in her bone marrow and blood were Id+. Six years after diagnosis, the patient died of respiratory failure due to infiltration of lungs by malignant cells. Autopsy revealed a dramatic change in the tumor cell morphology. The lungs, hilar nodes, and liver were infiltrated by a diffuse large cell lymphoma admixed with the leukemic cells. By immunohistologic staining these anaplastic lymphoma cells were IgM+/IgD-/lambda+ B cells expressing the same Id noted earlier on the CLL cells. The immunoglobulin gene rearrangement pattern on Southern blot analysis was also the same in leukemic blood cells and in the tissues involved by the lymphoma. Thus, the combination of antiidiotype and immunoglobulin gene analyses in this patient with Richter's syndrome revealed that a CLL clone, seemingly "frozen" in differentiation, was actually undergoing isotype switching, differentiation into plasma cells, and evolution into a rapidly growing and fetal lymphoma.  相似文献   
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Since 2011, outbreaks caused by influenza A(H3N2) variant [A(H3N2)v] viruses have become a public health concern in the United States. The A(H3N2)v viruses share the A(H1N1)pdm09 M gene containing the marker of M2 blocker resistance, S31N, but do not contain any known molecular markers associated with resistance to neuraminidase (NA) inhibitors (NAIs). Using a fluorescent NA inhibition (NI) assay, the susceptibilities of recovered A(H3N2)v viruses (n = 168) to FDA-approved (oseltamivir and zanamivir) and other (peramivir, laninamivir, and A-315675) NAIs were assessed. All A(H3N2)v viruses tested, with the exception of a single virus strain, A/Ohio/88/2012, isolated from an untreated patient, were susceptible to the NAIs tested. The A/Ohio/88/2012 virus contained two rare substitutions, S245N and S247P, in the NA and demonstrated reduced inhibition by oseltamivir (31-fold) and zanamivir (66-fold) in the NI assay. Using recombinant NA (recNA) proteins, S247P was shown to be responsible for the observed altered NAI susceptibility, in addition to an approximately 60% reduction in NA enzymatic activity. The S247P substitution has not been previously reported as a molecular marker of reduced susceptibility to the NAIs. Using cell culture assays, the investigational antiviral drugs nitazoxanide, favipiravir, and fludase were shown to inhibit the replication of A(H3N2)v viruses, including the virus with the S247P substitution in the NA. This report demonstrates the importance of continuous monitoring of susceptibility of zoonotic influenza viruses to available and investigational antiviral drugs.  相似文献   
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Translated from Khimiko-farmatsevitcheskii Zhurnal, Vol. 25, No. 4, pp. 24–26, April, 1991.  相似文献   
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