Publications by authors named "Samantha J McDonnel"

Feline immunodeficiency virus (FIV) is a naturally-occurring, large animal model of lentiviral-induced immunodeficiency syndrome, and has been used as a model of HIV pathogenesis and therapeutic interventions. HIV reservoirs in the form of latent virus remain the primary roadblock to viral eradication and cure, and FIV has been previously established an animal model of lentiviral latency. The goal of this study was to determine whether administration of the histone deacetylase inhibitor (HDACi) suberoylanilide hydroxamic acid (SAHA) to aviremic, chronically FIV-infected cats would induce latent viral reactivation in vivo.

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Objective: To assess genomic sequence conservation and variation in the proviral promoter of enzootic nasal tumor virus (ENTV) and Jaagsiekte sheep retrovirus (JSRV) in tissue samples from 3 sheep with nasal adenocarcinoma associated with ENTV and 3 sheep with pulmonary adenocarcinoma associated with JSRV and to identify a cell culture system that supports transcriptional activity of the ENTV and JSRV viral promoters.

Animals: 6 adult sheep.

Procedures: Standard PCR procedures for detection of the ENTV and JSRV long terminal repeat (LTR) promoter region were performed on samples from the 3 nasal adenocarcinomas and 3 pulmonary adenocarcinomas, respectively.

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Despite highly effective anti-retroviral therapy, HIV is thought to persist in patients within long-lived cellular reservoirs in the form of a transcriptionally inactive (latent) integrated provirus. Lentiviral latency has therefore come to the forefront of the discussion on the possibility of a cure for HIV infection in humans. Animal models of lentiviral latency provide an essential tool to study mechanisms of latency and therapeutic manipulation.

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FIV establishes a latent infection in peripheral CD4+ T-cells, and the latent FIV promoter is associated with deacetylated, methylated histones, consistent with a restrictive chromatin structure. Here we explored the use of 5 histone-modifying agents - 4 histone deacetylase inhibitors (HDACi) and 1 histone methyltransferase inhibitor (HMTi) - to reactivate latent FIV ex vivo. All compounds tested were able to alter histone lysine residue modifications in feline cells, both globally and at the FIV promoter locally.

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Feline immunodeficiency virus (FIV), the lentivirus of domestic cats responsible for feline AIDS, establishes a latent infection in peripheral blood CD4+ T-cells approximately eight months after experimental inoculation. In this study, cats experimentally infected with the FIV-C strain in the asymptomatic phase demonstrated an estimated viral load of 1 infected cell per approximately 10(3) CD4+ T-cells, with about 1 copy of viral DNA per cell. Approximately 1 in 10 proviral copies was capable of transcription in the asymptomatic phase.

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Two experiments examined English speakers' choices of count or mass compatible frames for nouns varying in imageability (concrete, abstract) and noun class (count, mass). Pairing preferences with equative (much/many) and non-equative (less/fewer) constructions were compared for groups of teenagers, young adults, and older adults. Deviations from normative usage were, for all ages, larger for count than for mass nouns, for the non-equative than for the equative construction, and for abstract count than for concrete count nouns.

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