Transforming growth factor-beta (TGF-β), a multifunctional cytokine regulating several immunologic processes, is expressed by virtually all cells as a biologically inactive molecule termed latent TGF-β (LTGF-β). We have previously shown that TGF-β activity increases during influenza virus infection in mice and suggested that the neuraminidase (NA) protein mediates this activation. In the current study, we determined the mechanism of activation of LTGF-β by NA from the influenza virus A/Gray Teal/Australia/2/1979 by mobility shift and enzyme inhibition assays.
View Article and Find Full Text PDFBackground: Vanadium pentoxide (V2O5) exposure is a cause of occupational bronchitis and airway fibrosis. Respiratory syncytial virus (RSV) is a ubiquitous pathogen that causes airway inflammation. It is unknown whether individuals with pre-existing respiratory viral infection are susceptible to V2O5-induced bronchitis.
View Article and Find Full Text PDFThe inhalation of vanadium pentoxide (V(2)O(5)) results in bronchitis and airway fibrosis. The lung fibrotic response to V(2)O(5) partially resolves where fibroblasts first proliferate and deposit collagen, but then undergo growth arrest and apoptosis. STAT-1 mediates fibroblast growth arrest and apoptosis.
View Article and Find Full Text PDFBackground: Exposure to vanadium pentoxide (V2O5) is a cause of occupational bronchitis. We evaluated gene expression profiles in cultured human lung fibroblasts exposed to V2O5 in vitro in order to identify candidate genes that could play a role in inflammation, fibrosis, and repair during the pathogenesis of V2O5-induced bronchitis.
Methods: Normal human lung fibroblasts were exposed to V2O5 in a time course experiment.
Background: Nanotechnology is a rapidly advancing industry with many new products already available to the public. Therefore, it is essential to gain an understanding of the possible health risks associated with exposure to nanomaterials and to identify biomarkers of exposure. In this study, we investigated the fibrogenic potential of SWCNT synthesized by chemical vapor deposition using cobalt (Co) and molybdenum (Mo) as catalysts.
View Article and Find Full Text PDFInfluenza A viruses continue to cause widespread morbidity and mortality. There is an added concern that the highly pathogenic H5N1 influenza A viruses, currently found throughout many parts of the world, represent a serious public health threat and may result in a pandemic. Intervention strategies to halt an influenza epidemic or pandemic are a high priority, with an emphasis on vaccines and antiviral drugs.
View Article and Find Full Text PDFThe first cases of infection caused by avian metapneumoviruses (aMPVs) were described in turkeys with respiratory disease in South Africa during 1978. The causative agent was isolated and identified as a pneumovirus in 1986. aMPVs have been detected in domestic nonpoultry species in Europe, but tests for the detection of these viruses are not available in the United States.
View Article and Find Full Text PDFEarlier findings from our laboratory based on analysis of nucleotide and predicted amino acid sequence identities of 15 avian pneumoviruses (APVs) isolated from the United States (subgroup C) demonstrated that the viruses were phylogenetically separated from the European subgroup A and subgroup B viruses. Here, we investigated whether viruses from the three subgroups were cross-reactive by testing field sera positive for each of the APV subgroups in an enzyme-linked immunosorbent assay (ELISA) test with recombinant matrix (M) and nucleoprotein (N) proteins generated from a Minnesota APV isolate (APV/MN2A). Sera from turkeys infected with APV subgroup A, B, or C reacted with recombinant M protein derived from APV/MN2A.
View Article and Find Full Text PDFAvian pneumoviruses (APVs) are RNA viruses responsible for upper respiratory disease in poultry. Experimental infections are typically less severe than those observed in field cases. Previous studies with APV and Escherichia coli suggest this discrepancy is due to secondary agents.
View Article and Find Full Text PDFThe avian pneumovirus (APV) outbreak in the United States is concentrated in the north-central region, particularly in Minnesota, where more outbreaks in commercial turkeys occur in the spring (April to May) and autumn (October to December). Comparison of the nucleotide and amino acid sequences of nucleoprotein (N), phosphoprotein (P), matrix (M), fusion (F), and second matrix (M2) genes of 15 U.S.
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