Publications by authors named "James Sheller"

Sleep-disordered breathing (SDB) is a contributor to atrial fibrillation (AF) and treatment of obstructive sleep apnea can reduce the recurrence of AF following catheter ablation. However, the effect of AF therapies on measures of SDB severity is less robustly described. We present the case of a middle-aged man with SDB and persistent AF who exhibited improvement in SDB metrics, as characterized by data downloaded from his auto-titrating continuous positive airway pressure (AutoCPAP) machine, very shortly following procedures that restored sinus rhythm.

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Rationale: Effective therapeutic interventions for chronic, idiopathic lung diseases remain elusive. Normalized T-cell function is an important contributor to spontaneous resolution of pulmonary sarcoidosis. Up-regulation of inhibitor receptors, such as programmed death-1 (PD-1) and its ligand, PD-L1, are important inhibitors of T-cell function.

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Objective: To determine the feasibility of administering iloprost by inhalation in patients with mild atopic asthma.

Methods: Volunteers underwent supervised inhalation of iloprost in the clinic with measurement of spirometry and blood pressure for 2 hours. The volunteers then inhaled iloprost four times daily at a dose of 2.

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Background: Current asthma guidelines recommend assessing the level of a patient's asthma control. Consequently, there is increasing use of asthma control as an outcome measure in clinical research studies. Several composite assessment instruments have been developed to measure asthma control.

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Background: In this descriptive case series, 80 soldiers from Fort Campbell, Kentucky, with inhalational exposures during service in Iraq and Afghanistan were evaluated for dyspnea on exertion that prevented them from meeting the U.S. Army's standards for physical fitness.

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Background: Acute asthma severity scores facilitate assessment and implementation of timely and appropriate therapy for pediatric patients but are complex and challenging for clinicians to use at the bedside.

Objective: To assess whether a simple, bedside acute asthma severity score comprising 3 standard clinical measures performs as well as more comprehensive asthma scores.

Methods: We prospectively enrolled participants 5 to 17 years of age with acute asthma exacerbations.

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Acute asthma exacerbations are one of the most common reasons for paediatric emergency department visits and hospitalisations, and a relapse frequently necessitates repeat urgent care. While care plans exist, there are no acute asthma prediction rules (APRs) to assess severity and predict outcome. The primary objective of the Acute Asthma Severity Assessment Protocol study is to develop a multivariable APR for acute asthma exacerbations in paediatric patients.

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Objective: To determine if African American and European American children with asthma admitted to an intensive care unit (ICU) had different characteristics, we conducted a retrospective chart review of asthma admissions to the region's only pediatric ICU.

Patients And Methods: A chart review was performed on 125 patients with asthma admitted to the pediatric critical care unit at Vanderbilt Children's Hospital. Descriptive statistics, clinical characteristics, and disparities in care were compared using either Fisher's exact tests or Wilcoxon ranksum tests.

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Nuclear factor kappa B (NF-kappa B) is a critical transcription factor for the production of many inflammatory cytokines. It is activated in the airway epithelium of human asthmatics and in mice after allergic stimulation. To examine the role of NF-kappa B activation in allergic inflammation, the authors generated transgenic mouse lines that allowed for the inducible stimulation of NF-kappa B in airway epithelial cells.

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African Americans are disproportionately affected by asthma. Social and economic factors play a role in this disparity, but there is evidence that genetic factors may also influence the development of asthma and response to therapy in African American children. Our hypothesis is that variations in asthma related genes contribute to the observed asthma disparities by influencing the response to asthma-specific therapy.

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Background: Invariant natural killer T (iNKT) cells produce cytokines that can influence the immune response to infection or allergen. Controversy surrounds their role in exacerbations of human atopic asthma.

Objectives: To determine the effect of allergen challenge on iNKT cells' mobilization to the airways and blood and to establish the relationship between airway iNKT cells and bronchial sensitivity to methacholine and allergen in patients with atopic asthma.

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The Shanghai Women's Asthma and Allergy Study is the first population-based incidence study designed to assess the associations of dietary antioxidant intake and measures of oxidative stress and antioxidant enzyme activity with development of adult-onset asthma and allergic rhinitis. A total of 65,732 participants in the Shanghai Women's Health Study, an ongoing cohort study in seven districts of Shanghai, People's Republic of China, were recruited to the Shanghai Women's Asthma and Allergy Study from 2003 to 2007. Dietary intake was assessed in the parent study by using a validated and quantitative food frequency questionnaire at baseline recruitment and at the first biennial follow-up survey.

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To investigate changes in oxidant stress during and following acute asthma exacerbations, this study measured 2,3-dinor-5,6-dihydro-15-F(2t)-IsoP (F(2)-IsoP-M), the major urinary metabolite of 15-F(2t)-IsoP, in eight asthmatic adults, during and following an asthma hospitalization. F(2)-IsoP-M concentrations at admission and follow-up were significantly higher than discharge (admission median: 4.12 ng/Cr mg, range 1.

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Although airway epithelial cells provide important barrier and host defense functions, a crucial role for these cells in development of acute lung inflammation and injury has not been elucidated. We investigated whether NF-kappaB pathway signaling in airway epithelium could decisively impact inflammatory phenotypes in the lungs by using a tetracycline-inducible system to achieve selective NF-kappaB activation or inhibition in vivo. In transgenic mice that express a constitutively active form of IkappaB kinase 2 under control of the epithelial-specific CC10 promoter, treatment with doxycycline induced NF-kappaB activation with consequent production of a variety of proinflammatory cytokines, high-protein pulmonary edema, and neutrophilic lung inflammation.

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The allergic inflammation occurring in asthma is believed to be accompanied by the production of free radicals. To investigate the role of free radicals and the cells affected we turned to a murine model of allergic inflammation produced by sensitization to ovalbumin with subsequent aerosol challenge. We examined oxidant stress by measuring and localizing the sensitive and specific marker of lipid peroxidation, the F2-isoprostanes.

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F2-isoprostanes are produced in vivo by nonenzymatic peroxidation of arachidonic acid esterified in phospholipids. Increased urinary and plasma F2-isoprostane levels are associated with a number of human diseases. These metabolites are regarded as excellent markers of oxidant stress in vivo.

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Cyclooxygenase (COX) inhibition during allergic sensitization and allergen airway challenge results in augmented allergic inflammation. We hypothesized that this increase in allergic inflammation was dependent on increased generation of leukotrienes that results from COX inhibition, as leukotrienes are important proinflammatory mediators of allergic disease. To test this hypothesis, we allergically sensitized and challenged mice deficient in 5-lipoxygenase (5-LO).

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Background: Respiratory syncytial virus (RSV) is the leading infectious cause of respiratory failure and wheezing in infants and young children. Prematurity is the greatest risk factor for severe RSV-induced disease, and recent studies suggest that premature children have lower levels of the type I IFNs (alpha/beta), for which signal transducer and activator of transcription (STAT) 1 is a critical intracellular signaling molecule.

Objective: We hypothesized that RSV infection in STAT 1 knockout (STAT 1 KO) mice would result in both increased airway resistance and airway hyperresponsiveness.

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Two postulated intrinsic anti-inflammatory mechanisms in asthma include the low affinity IgE receptor, or CD23, and interleukin 1 receptor antagonist (IL-1ra). We investigated the role these mediators play in the asthmatic response by measuring local levels in human asthmatics before and after segmental allergen challenge and examined the effect of inhaled corticosteroids on soluble CD23 and IL-1ra levels. Ten subjects underwent bronchoscopy at baseline and 24 hours after antigen challenge.

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Nonselective cyclooxygenase (COX) inhibition during the development of allergic disease in a murine model causes an increase in type 2 cytokines and lung eosinophilia; however, the mechanisms responsible for this augmented allergen-induced inflammation have not been examined. Ab depletion of CD4 and CD8 cells revealed that the heightened allergic inflammation caused by COX inhibition was CD4, but not CD8, dependent. Allergen sensitization and airway challenge alone led to undetectable levels of IL-5 and IL-13 in the lungs of IL-4, IL-4Ralpha, and STAT6 knockout (KO) mice, but COX inhibition during the development of allergic inflammation resulted in wild-type levels of IL-5 and IL-13 and heightened airway eosinophilia in each of the three KO mice.

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Background: Microbial infections are associated with the initial susceptibility to and flares of asthma. However, immunologic mechanisms whereby infections might alter the asthmatic phenotype are lacking.

Objective: To test the hypothesis that memory T cells specific both for a viral antigen and an allergen could influence the pathogenesis of allergic disease in vivo .

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Isoketals are highly reactive gamma-ketoaldehydes formed by the oxidation of arachidonic acid that rapidly adduct to proteins. To investigate the formation of isoketal adducts in vivo, we isolated and characterized a single-chain antibody from a phage displayed recombinant ScFv library that bound a model peptide adducted with synthetic 15-E2-isoketal. Recognition of isoketal adduct by this anti-isoketal adduct single-chain antibody was essentially independent of the amino acid sequence of adducted peptides or proteins.

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Effector and memory T lymphocytes differ significantly, and there is no experimental evidence that memory cells are sufficient to render an otherwise normal individual susceptible to localized allergic inflammation. Furthermore, nothing is known about the kinetics of memory responses after inhalation of antigen or interplay between an allergen-specific memory helper T (Th) cell Th2 population and uncommitted or competing Th1 cells. To study these processes, T cell receptor-transgenic CD4(+) effector cells were generated in vitro, transferred into naive recipients, and allowed to resume a quiescent state.

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Background: There is increasing evidence that injury to the liver can precipitate or exaggerate lung injury. We have previously shown that hepatic cryoablation (cryo) causes activation of nuclear factor (NF)-kappaB, cytokinemia (tumor necrosis factor-alpha, Mouse Macrophage Inflammatory Protein-2 [MIP-2]), and lung inflammation in transgenic HLL (5'HIV-LTR-Luciferase gene) mice and in Sprague-Dawley rats. It has been reported that BALB/c mice are susceptible to traumatic injury and are active immune responders.

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