Clinical and experimental allergy : journal of the British Society for Allergy and Clinical Immunology
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The mediator mechanisms of the cutaneous wheal and flare response, which underlies allergic skin and urticarial conditions, are controversial. The wheal results primarily from a direct effect of histamine on the local vascular bed but to what extent does histamine diffuse within the wheal? The flare is neurogenic, in origin, being disseminated within the dermis by axon reflexes, but do the neuropeptides released from the nerve endings cause the vasodilatation directly or do they induce the further release of histamine which then transduces the flare? ⋯ These data support the theory that the flare reaction to focal histamine injection or release is a neurogenic reflex not involving histamine release at its effector end.
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Asthma, together with, in some cases, anaphylaxis, was observed in seven subjects following ingestion of royal jelly, a secretion of honey bees which is used as a health tonic. ⋯ Symptoms of asthma and anaphylaxis seen in subjects following ingestion of royal jelly were true IgE-mediated hypersensitivity reactions. The clinical significance of the antibodies found in the sera of control subjects is not known but they may arise in response to common inhalant allergens that show allergenic cross-reactivity with royal jelly.
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Randomized Controlled Trial Comparative Study Clinical Trial
Comparison of the effects of salmeterol and salbutamol on clinical activity and eosinophil cationic protein serum levels during the pollen season in atopic asthmatics.
In atopic asthma there is strong evidence of eosinophils playing an active role in pathogenesis. Some investigations demonstrated that eosinophil cationic protein (ECP) serum levels increased in atopic patients with asthma during pollen season. ⋯ This study demonstrates that salmeterol affords a significant improvement in asthma control during the pollen season, measured by both subjective and objective parameters, compared with salbutamol. This greater efficacy may be related to inhibition of eosinophil degranulation during the pollen season.
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Comparative Study Clinical Trial
Polymerase chain reaction quantification of cytokine messenger RNA expression in peripheral blood mononuclear cells of patients with acute exacerbations of asthma: effect of glucocorticoid therapy.
We have measured the expression of messenger ribonucleic acid (RNA) (mRNA) encoding interleukin-5 (IL-5), IL-4, IL-2 and interferon-gamma (IFN gamma) in peripheral blood mononuclear cells (PBMC) from 10 patients with acute exacerbations of asthma and nine non-asthmatic controls. Measurements were repeated in seven of the asthmatics following 7 days of oral glucocorticoid therapy. Total RNA was extracted from the PBMC, reverse transcribed using oligo-(dT) primers and aliquots of the resulting complementary DNA (cDNA) amplified using the polymerase chain reaction (PCR) in the presence of cytokine-specific primers under non-saturating conditions. ⋯ We conclude that PBMC of patients with acute exacerbations of asthma demonstrate elevated expression of mRNA encoding IL-5, but not IL-2, IL-4 and IFN gamma and that the clinical improvement associated with glucocorticoid therapy is associated with a reduction of IL-5 mRNA expression. We further conclude that elevated expression in PBMC of mRNA encoding IL-4 is a feature of atopy but not of asthma. These observations suggest that IL-5 synthesis by activated T-lymphocytes may be relevant to the pathogenesis of asthma, and that inhibition of this release by glucocorticoids may at least partly explain their therapeutic effect in this disease.