Publications by authors named "Charles A Stewart"

Mouse CMV (MCMV) infection rapidly induces the proliferation of NK cells, which correlates with immunological protection. Whether NK cells primed during acute response against MCMV are maintained for the long term is not known. In this study, we used TcrdH2BeGFP mice in which maturing NK cells are genetically labeled with a pulse of very stable histone-2B-eGFP.

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Background/objectives: Knowledge of spinal cord injury (SCI) bone changes has been derived primarily through cross-sectional studies, many of which are controvertible. Longitudinal studies are sparse, and long-term longitudinal chronic studies are unavailable. The objective of this study was to provide a clearer perception of chronic longitudinal bone variations in people with complete SCI.

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Background And Aims: GPCR stimulation by various ligands including histamine has been shown to transactivate the epidermal growth factor receptor (EGFR). This study examines the functional interactions between the H2 receptor and the EGFR in the regulation of matrix metalloproteinase-1 (MMP-1) secretion and gene expressions in cultured gastric epithelial cells.

Methods: AGS cells were incubated for up to 24 h with either histamine or heparin binding-epidermal growth factor (HB-EGF) and MMP-1 release was determined by immunoassay.

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Inflammation has been increasingly recognized to play an important role in the pathogenesis of Parkinson's disease (PD). Using immunocytochemistry and electron microscopy, we found that intranigral injection of lipopolysaccharide (LPS) caused marked microglial activation and a dose-dependent selective loss of dopaminergic neurons, which was mediated by apoptosis as evidenced by prominent TUNEL labeling. RNase protection assays revealed that mRNA for Bax, Fas and the pro-inflammatory cytokines interleukin (IL)-1α, IL-1β, IL-6 and tumor necrosis factor (TNF)-α were significant increased ipsilaterally in LPS-injected side of SN, while expression of the anti-apoptotic gene Bcl-2 was decreased.

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NK cells and gammadelta T cells are distinct subsets of lymphocytes that contextually share multiple phenotypic and functional characteristics. However, the acquisition and the extent of these similarities remain poorly understood. Here, using T cell receptor delta locus-histone 2B-enhanced GFP (Tcrd-H2BEGFP) reporter mice, we show that germ-line transcription of Tcrd occurs in all maturing NK cells.

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The aims of this study were to examine the ability of the antioxidant N-acetylcysteine (NAC) and mesalamine (5-ASA) alone and in combination to affect TNBS-induced colitis in rat. Three days following induction of TNBS colitis rats were randomized to receive daily intracolonic treatment with NAC, 5-ASA, and NAC plus 5-ASA for 5 or 8 days. At the end of the treatment period macroscopic and microscopic colonic injuries were scored.

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Our recent studies have demonstrated that generation of ROS is associated with choline deficiency (CD)-induced apoptosis in CWSV-1 cells, an immortalized rat hepatocyte that becomes tumorigenic by stepwise culturing in decreasing levels of choline. In the present study, we investigated the effect of CD on loss of mitochondrial membrane potential (MMP), using the JC-1 probe by FASCAN assay. Our data demonstrate that MMP in CD-cultured cells was decreased in a time- and dose-dependent manner and that significant disruption occurred at 24 h, relative to high choline (HC, 70 microM) cultured cells.

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Choline deficiency (CD) is involved in hepatocellular carcinoma and CD-induced apoptosis may be implicated in cellular malignant transformation. In this report, we studied the effects of choline deficiency on generation of reactive oxygen species (ROS) using the fluorescent probe dichlorodihydrofluorescein diacetate and the possible role of ROS on CD-induced apoptosis in cultured CWSV-1 cells, an immortalized rat hepatocyte. This cell line is reported to become tumorigenic by step-wise culturing in lower levels of choline.

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To determine the body composition differences across age, 133 men with chronic spinal cord injury (SCI) (66 with tetraplegia, 67 with paraplegia) were compared with an age-, height-, and ethnicity-matched able-bodied male reference population (n = 100) using two different dual-energy X-ray absorptiometry densitometers. The effects of duration of injury, level, and completeness of lesion were analyzed in the SCI population. Independent of age, total body and regional lean mass were lower and fat mass was higher in persons with SCI compared with controls.

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The free radical trapping compound phenyl N-tert-butylnitrone (PBN) provides potent protection against lethal endotoxemia in rodents, but the mechanism of this protection is not well understood. The objective of this study was to show that PBN administration in lipopolysaccharide- (LPS) induced endotoxemia promotes enhanced production of endogenous interleukin 10 (IL-10), and the expressed IL-10 is a causal factor in the protection from endotoxemia. We show the amplified expression of IL-10 in liver and plasma in PBN- (150 mg/kg) plus LPS- (4 mg/kg) treated rats using ribonuclease protection assay (RPA) and ELISA.

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