Publications by authors named "Jerry Barnhart"

Autofluorescence (AF) is a feature of all cell types, though some have more than others. In tissues with complex heterogeneous cellularity, AF is frequently a source of high background, masking faint fluorescent signals and reducing the available dynamic range of detectors for detecting fluorescence signals from markers of interest in a flow cytometry panel. Pulmonary flow cytometry presents unique challenges because lung cells are heterogeneous and contain varying amounts of high AF.

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The cell division controller Cdc6 plays a central role in the initiation of DNA replication. It was found that elevated levels of Cdc6 were present in many of human cancer cells, and the accumulation of Cdc6 is required for cell proliferation. In this study, we have investigated the control of Cdc6 expression and its effect on cell proliferation and death in human neuroblastoma cells.

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The F7-26 monoclonal antibody (Mab) has been reported to be specific for single-strand DNA damage (ssDNA) and to also identify cells in apoptosis. We carriedout studies to determine if F7-26 binding measured by flow cytometry was able to specifically identify exogenous ssDNA as opposed to DNA damage from apoptosis. Neuroblastoma cells were treated with melphalan (L-PAM), fenretinide, 4-hydroperoxycyclophosphamide (4-HC)+/-pan-caspase inhibitor BOC-d-fmk, topotecan or with 10Gy gamma radiation+/-hydrogen peroxide (H2O2) and fixed immediately postradiation.

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Activation of T-cells by antigens initiates a complex series of signal-transduction events that are critical for immune responses. While kinases are key mediators of signal transduction networks, several of which have been well characterized in T-cell activation, the functional roles of other kinases remain poorly defined. To address this deficiency, we developed a genetic screen to survey the functional roles of kinases in antigen mediated T-cell activation.

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CD1d-restricted Valpha24-invariant natural killer T cells (iNKTs) are important in immunoregulation. CD4(+) and CD4(-) iNKTs develop with similar frequencies in murine thymus and depend on interleukin-15 (IL-15) in periphery. However, homeostatic requirements of iNKTs have not been analyzed in humans.

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