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ABSTRACT: Epithelial barrier dysfunction is critical in the induction of allergy; the aetiology is to be further understood. A recent report indicates that CD98 plays a role in the intestinal epithelial barrier dysfunction.
This study aimed to investigate the role of overexpression of CD98 in the induction of nasal allergy.
The nasal epithelium samples were collected from 30 patients with allergic rhinitis and 30 healthy subjects. The contents of CD98 and Staphylococcal enterotoxin B (SEB) in the nasal epithelium samples were evaluated by using Western blotting. The effect of SEB of inducing the expression of CD98 was evaluated with an airway epithelial cell line, the 16HBE14o cells. The epithelial barrier function was assessed with the indicators of transepithelial resistance (TER) and permeability to horseradish peroxidase (HRP). A mouse model was employed to evaluate the role of CD98 in the induction of nasal allergy.
High levels of CD98 and SEB were detected in the nasal epithelium of patients with allergic rhinitis. A positive correlation was identified between CD98 and SEB in nasal epithelium samples. Exposure to SEB could induce the overexpression of CD98 in RPMI 2650 and 16HBE14o cells. The overexpression of CD98 down-regulated TER and increased the permeability to HRP in 16HBE14o monolayers. Concurrent exposure to SEB and OVA induced nasal allergies in a mouse model that could be blocked by pre-treatment with anti-CD98 antibody.
CD98 plays a critical role in compromising the airway epithelial barrier function that contributes to the induction of airway allergy.
Clinical & Experimental Allergy 07/2012; 42(7):1051-9. · 5.03 Impact Factor
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ABSTRACT: The breakdown of immune tolerance plays a critical role in allergic disorders; the mechanism of breaching immune tolerance remains largely unknown.
The present study aimed to investigate the role of Staphylococcal enterotoxin B (SEB) in the interference of the immune tolerance in the nasal mucosa.
The immune tolerant components, tolerogenic dendritic cells (TolDC) and regulatory T cells (Treg), were assessed in the surgically removed nasal mucosa from patients with allergic rhinitis (AR) or non-AR chronic rhinitis. The contents of SEB and integrin alphavbeta6 (avb6) in the nasal epithelium were assessed using enzyme-linked immunoassay. The ability of avb6 on TolDC induction and the effect of SEB on suppression of avb6 in nasal epithelial cells were observed in cell culture.
Compared with that in the non-AR nasal mucosa, the frequencies of TolDCs/Tregs were lower, the contents of SEB were higher and the contents of avb6 were lower in the AR nasal mucosa. Avb6 had the ability to induce the development of TolDCs in vitro; the latter had the ability to induce Treg development. The expression of avb6 was detected in nasal epithelial cells in culture that could be suppressed by SEB.
The components of immune tolerance machinery, TolDCs and Tregs were suppressed in the AR nasal mucosa. The increases in SEB and decreases in avb6 in nasal epithelium are associated with the compromises of immune tolerance in the nasal mucosa. SEB has the ability to suppress the expression of avb6 in nasal epithelial cells.
Clinical & Experimental Allergy 09/2011; 42(3):375-82. · 5.03 Impact Factor
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Advanced Functional Materials 08/2005; 15(9):1523 - 1528. · 10.18 Impact Factor
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ABSTRACT: The present article reports on recent work from this laboratory that has led to advances in several areas of the field of photoinitiated cationic polymerization. Two different classes of novel photoinitiators 5-arylthianthrenium salts and 4-hydroxyphenyl dialkylsulfonium salts have been prepared and their use in the polymerization of various monomer systems studied. Also described is the development of both monomeric and polymeric photosensitizers that may be employed to broaden the spectral sensitivity of various onium salt photoinitiators. Acceleration of rate of the ring-opening polymerization of epoxide monomers has been achieved through the use of benzyl alcohols. Further, benzyl alcohols bearing sensitizing groups were found to be especially interesting as combination accelerators-photosensitizers. Lastly, epoxy monomers having groups with easily abstractable protons display exceptional reactivity in photoinitiated ring-opening cationic polymerization. A mechanism has been proposed to explain this observation.
Macromolecular Symposia 09/2004; 215(1):165 - 178.
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ABSTRACT: This paper describes a systematic approach for extracting the lumped circuit parameters of microstrip discontinuities from their S-parameter characteristics—which are assumed to be known—by using a three- step procedure. We begin by computing the lumped equivalent circuit parameters, e.g., L, C, R and/or G, with a direct extraction procedure, which relates the S-parameters to the Z- (or Y-) parameters of the discontinuity. Next, we use these values as initial guesses for an optimization code based on the genetic algorithm, to obtain circuit parameters that are invariant over a specified frequency range. Finally, we develop an artificial neural network model for predicting the values of these circuit elements rapidly as we change the physical and electrical parameters of the discontinuity, for instance the width or height of the etch, and the complex dielectric constant of the substrate. The application of the direct extraction technique is first illustrated by considering a number of representative two-port microstrip discontinuities, viz., the chamfered bend and gap discontinuities. It is then extended to three-port structures, for instance, a T-junction. The validation is given for the case examples investigated by comparing the S-parameter calculated from the equivalent circuit with those obtained from a full-wave EM solver. We also use the chamfered bend as a case example to illustrate the application of this three-step procedure. Copyright © 2002 John Wiley & Sons, Ltd.
International Journal of Numerical Modelling Electronic Networks Devices and Fields 01/2002; 15(1):59 - 72. · 0.60 Impact Factor
