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University of Nebraska - Lincoln

1994

Virology

Articles 1 - 6 of 6

Full-Text Articles in Life Sciences

Correlation Between Precolonization Of Trigeminal Ganglia By Attenuated Strains Of Pseudorabies Virus And Resistance To Wild-Type Virus Latency, L. M. Schang, G. F. Kutish, Fernando A. Osorio Dec 1994

Correlation Between Precolonization Of Trigeminal Ganglia By Attenuated Strains Of Pseudorabies Virus And Resistance To Wild-Type Virus Latency, L. M. Schang, G. F. Kutish, Fernando A. Osorio

Nebraska Center for Virology: Faculty Publications

We compared the levels of latent pseudorabies virus (PRV) DNA in trigeminal ganglia (TG) of pigs after intranasal inoculation of different PRV strains by using quantitative DNA PCR. The extent of colonization attained in each case varied significantly according to the type of strain and inoculum dose, wild-type (WT) PRV being the most efficient strain in colonizing TG. When groups of pigs representing different levels of precolonization of TG with an attenuated PRV strain were challenged with WT PRV, it became evident that there is a statistically significant inverse correlation between the extent of precolonization attained by an attenuated PRV …


Alpha Interferon-Induced Antiretroviral Activities: Restriction Of Viral Nucleic Acid Synthesis And Progeny Virion Production In Human Immunodeficiency Virus Type 1-Infected Monocytes, Lisa Baca-Regen, Nina Heinzinger, Mario Stevenson, Howard Gendelman Nov 1994

Alpha Interferon-Induced Antiretroviral Activities: Restriction Of Viral Nucleic Acid Synthesis And Progeny Virion Production In Human Immunodeficiency Virus Type 1-Infected Monocytes, Lisa Baca-Regen, Nina Heinzinger, Mario Stevenson, Howard Gendelman

Nebraska Center for Virology: Faculty Publications

Alpha interferon (IFN-a) restricts multiple steps of the human immunodeficiency virus type 1 (HIV-i) life cycle. A well-described effect of IFN-a is in the modulation of viral nucleic acid synthesis. We demonstrate that IFN-α influences HIV-1 DNA synthesis principally by reducing the production of late products of reverse transcription. The magnitude of IFN-α-induced downregulation of HIV-1 DNA and/or progeny virion production was dependent on the IFN-α concentration, the duration of cytokine administration, the multiplicity of infection, the viral strain, and the cycles of viral infection. Interestingly, reductions in viral DNAs could not fully account for the observed IFN-a-induced abrogation of …


Enhanced Competitiveness Of Tomato Bushy Stunt Virus Defective Interfering Rnas By Segment Duplication Or Nucleotide Insertion, K. Andrew White, Thomas Jack Morris Sep 1994

Enhanced Competitiveness Of Tomato Bushy Stunt Virus Defective Interfering Rnas By Segment Duplication Or Nucleotide Insertion, K. Andrew White, Thomas Jack Morris

Nebraska Center for Virology: Faculty Publications

We have analyzed atypical tomato bushy stunt virus defective interfering (DI) RNA species which accumulated during a passage series in protoplasts. We present a rationale for the order of appearance of these molecules and show, using competition assays, that either segment duplication or single nucleotide insertion can enhance DI RNA competitiveness. Possible mechanisms for the introduction of the modifications observed in these DI RNAs are discussed.


Purification And Characterization Of Two Forms Of A High-Molecular-Weight Cysteine Proteinase (Porphypain) From Porphyromonas Gingivalis, Pawel Ciborowski, Makoto Nishikata, Roger D. Allen, Marilyn S. Lantz Aug 1994

Purification And Characterization Of Two Forms Of A High-Molecular-Weight Cysteine Proteinase (Porphypain) From Porphyromonas Gingivalis, Pawel Ciborowski, Makoto Nishikata, Roger D. Allen, Marilyn S. Lantz

Nebraska Center for Virology: Faculty Publications

Porphyromonas gingivalis, an organism implicated in the etiology and pathogenesis of human periodontal diseases, produces a variety of potent proteolytic enzymes, and it has been suggested that these enzymes play a direct role in the destruction of periodontal tissues. We now report that two cell-associated cysteine proteinases of P. gingivalis W12, with molecular masses of approximately 150 kDa (porphypain-1) and 120 kDa (porphypain-2), as determined by sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis, have been separated and purified to apparent homogeneity. These proteinases appear to be SDS-stable conformational variants of a 180-kDa enzyme, and they are the largest cysteine proteinases …


Molecular Analysis Of The Rfb Gene Cluster Of A Group D2 Salmonella Enterica Strain: Evidence For Its Origin From An Insertion Sequence-Mediated Recombination Event Between Group E And Dl Strains, Shi-Hua Xiang, Matthew Hobbs, Peter R. Reeves Jul 1994

Molecular Analysis Of The Rfb Gene Cluster Of A Group D2 Salmonella Enterica Strain: Evidence For Its Origin From An Insertion Sequence-Mediated Recombination Event Between Group E And Dl Strains, Shi-Hua Xiang, Matthew Hobbs, Peter R. Reeves

Nebraska Center for Virology: Faculty Publications

The Salmonella enterica O antigen is a highly variable surface polysaccharide composed of a repeated oligosaccharide (the O unit). The O unit produced by serogroup D2 has structural features in common with those of groups Dl and El, and hybridization studies had previously suggested that the D2 rfb gene cluster responsible for O-unit biosynthesis is indeed a hybrid of the two. In this study, the rfb gene cluster was cloned from a group D2 strain of S. enterica sv. Strasbourg. Mapping, hybridization, and DNA sequencing showed that the organization of the D2 rfb genes is similar to that of group …


Nonhomologous Rna Recombination In Tombusviruses: Generation And Evolution Of Defective Interfering Rnas By Stepwise Deletions, K. Andrew White, Thomas Jack Morris Jan 1994

Nonhomologous Rna Recombination In Tombusviruses: Generation And Evolution Of Defective Interfering Rnas By Stepwise Deletions, K. Andrew White, Thomas Jack Morris

Nebraska Center for Virology: Faculty Publications

We used a protoplast system to study the mechanisms involved in the generation and evolution of defective interfering (DI) RNAs of tomato bushy stunt tombusvirus (TBSV). Synthetic transcripts corresponding to different naturally occurring TBSV DI RNAs, or to various artificially constructed TBSV defective RNAs, were analyzed. The relative levels of competitiveness of different DI RNAs were determined by coinoculating their corresponding transcripts into protoplasts along with helper genomic RNA transcripts and monitoring the level of DI RNA accumulation. Further studies were performed to assess the contribution of naked DI RNA stability and DI RNA encapsidation efficiency to the observed levels …