Publications by authors named "Ronald J Harbeck"

Although skin-prick testing (SPT) is commonly used by allergists in the evaluation of allergy, in-vitro testing for specific IgE (sIgE) is an attractive alternate because it can be performed remotely and is of utility when SPT is contraindicated, as in patients on anti-histamines, or with dermatitis or severe eczema. It is, however, necessary to determine the extent of correlation between the in-vitro and in-vivo methods. In this study, we examined the qualitative concordance between SPT and sIgE as measured on the HYTEC™288 platform for 10 commonly encountered inhalant allergens in 232 subjects, and analysed the performance characteristics for the HYTEC™288.

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Background: Deficient production of reactive oxygen species (ROS) by the phagocyte nicotinamide adenine dinucleotide (NADPH) oxidase in patients with chronic granulomatous disease (CGD) results in susceptibility to certain pathogens secondary to impaired oxidative killing and mobilization of other phagocyte defenses. Peroxisome proliferator-activated receptor (PPAR) γ agonists, including pioglitazone, approved for type 2 diabetes therapy alter cellular metabolism and can heighten ROS production. It was hypothesized that pioglitazone treatment of gp91(phox-/-) mice, a murine model of human CGD, would enhance phagocyte oxidant production and killing of Staphylococcus aureus, a significant pathogen in patients with this disorder.

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The majority of human subjects who receive subcutaneous allergen immunotherapy (IT) develop decreased sensitivity to their allergens. Multiple factors may explain the efficacy of IT, some evidence support a role for allergen specific IgG antibodies. There is controversy whether such antibodies act by blocking allergen binding to IgE or initiation of active inhibitory signaling through low affinity IgG receptors (FcgammaRIIB) on mast cells and basophils.

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Background: To date, there have been no randomized, double-blind studies showing the effectiveness of sublingual immunotherapy with multiple allergens.

Objective: The purpose of this study was to examine whether the efficacy of sublingual immunotherapy (SLIT) with standardized timothy extract was reduced by combination with other allergen extracts.

Methods: A single-center, randomized, double-blind, placebo-controlled trial with SLIT was conducted.

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Rationale: Respiratory Mycoplasma pneumoniae (Mp) infection is involved in asthma pathobiology, but whether the established allergic airway inflammation compromises lung innate immunity and subsequently predisposes patients with asthma to Mp infection remains unknown.

Objectives: To test whether the established allergic airway inflammation compromises host innate immunity (e.g.

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Cigarette smoke has a major impact on health issues worldwide. Although genetics certainly is a factor in the sensitivity to cigarette smoke, other lung environmental factors, such as infection, potentially could interact with cigarette smoke to induce inflammatory changes associated with various diseases. Four groups of BALB/c mice (smoking only; smoking + M.

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Background: Approximately 40% of patients with chronic idiopathic urticaria have antibodies to the alpha subunit of the high-affinity IgE receptor. CD203c is a basophil activation marker known to be upregulated by cross-linking of the FcepsilonRIalpha receptor and may serve as a useful marker to identify these patients.

Objective: The primary objective was to assess the affect of sera from patients with chronic idiopathic urticaria on basophil CD203c expression.

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Respiratory Mycoplasma pneumoniae (Mp) infection is involved in several acute and chronic lung diseases including community-acquired pneumonia, asthma and chronic obstructive pulmonary disease. In the chronic disease process, recurrent respiratory bacterial infections could occur, which may result in varying degrees of symptoms and lung inflammation among patients. However, the lung immunologic differences of host responses to repeated bacterial (i.

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Background: Commercial and residential buildings can become contaminated with molds, which may trigger allergic disorders. Mold remediation efforts may require costly replacement of mold-contaminated building materials. Disinfectants that contain dilute sodium hypochlorite can kill mold and are practical to use.

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Excessive airway mucin production contributes to airway obstruction in lung diseases such as asthma and chronic obstructive pulmonary disease. Respiratory infections, such as atypical bacterium Mycoplasma pneumoniae (Mp), have been proposed to worsen asthma and chronic obstructive pulmonary disease in part through increasing mucin. However, the molecular mechanisms involved in infection-induced airway mucin overexpression remain to be determined.

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Surfactant Protein A (SP-A) is an abundant, multifunctional lectin that resides within the bronchoalveolar compartment of the lung and plays an important role in the innate immunity of the organ. Mycoplasma pneumoniae is a human pathogen that resides in the same compartment as SP-A, and we examined the interaction between the two. Preparations of human and rat SP-A recognized the mycoplasma with high affinity in the presence of Ca(2+), exhibiting apparent K(')(d) values in the nanomolar range.

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Background: Mycoplasma pneumoniae has been shown to induce airway inflammation and bronchial hyperresponsiveness (BHR) in mice. Inhaled corticosteroids are the mainstay of asthma treatment, but their effects on M. pneumoniae and associated airway inflammation and BHR are poorly understood.

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A mixture of lysophosphatidylcholines (lyso-PCs) are generated during blood storage and are etiologic in models of acute lung injury. We hypothesize that lyso-PCs stimulate polymorphonuclear neutrophils (PMNs) through Ca(2)(+)-dependent signaling. The lyso-PC mix (0.

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Airway mycoplasma infection may be associated with asthma pathophysiology. However, the direct effects of mycoplasma infection on asthma remain unknown. Using a murine allergic-asthma model, we evaluated the effects of different timing of airway Mycoplasma pneumoniae infection on bronchial hyperresponsiveness (BHR), lung inflammation, and the protein levels of Th1 (gamma interferon [IFN-gamma]) and Th2 (interleukin 4 [IL-4]) cytokines in bronchoalveolar lavage fluid.

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Increasing evidence now identifies surfactant protein D (SP-D) as an important element of the innate immune system of the lung. In this study, we examined the interactions of rat and human SP-D with the human pathogen, Mycoplasma pneumoniae. Rat and human SP-D bound the organism with high affinity in a reaction that required Ca(2+) and was inhibited by EGTA.

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