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Notes: The effect of treatment with astemizole (Hismanal®) on symptoms elicited by ingestion of hazelnuts in birch pollen-allergic patients (the oral allergy syndrome) was investigated. Thirty patients with a well-documented allergy to silver birch, experiencing symptoms when ingesting hazelnuts, were included in the study. All had a positive skin prick test (SPT) to birch, whereas 29 and 27, respectively, showed a positive RAST and basophil histamine release test (HR) to birch. In contrast, only 15 patients had a positive SPT to hazelnut, 13 had a positive RAST, whereas 24 had a positive HR. Alter two oral provocations with hazelnuts the patients were randomized to receive either 10 mg of astemizole or placebo daily for 2 weeks in a double blind protocol followed by two oral provocations. Treatment with astemizole significantly reduced the symptoms compared with placebo (P= 0.004); however, without completely abolishing the symptoms.

Notes: The aim was to compare IgE and IgG4, RAST-inhibition assay (RI), monoclonal antibody ELISA (Mab-ELISA), counter current immuno electrophoresis (CCIE) and histamine release from basophil leukocytes (HR) for allegen quantification with special reference to aeroallergen detection. As components of indoor acroallergens, cat, dog, and Derm. pter. allergen extracts were selected for the experiments. To evaluate unspecific interference, these allergens were compared mutually and with Cladosporium herbarum. Allergen extracts in varying dilutions were mixed with crushed glass fibre filter materials, eluted, recovered by centrifugation, and allergen concentration quantified by the assays. Equal sensitivity was found for both IgE- and IgG4-RI assaying eat allergen (in the range 5 − 50 SQ-U/ml) and dog allergen (in the range 102− 103 SQ-U/ml). The IgG4-RI assaying Derm. pter, was more sensitive (50 SQ-U/ml) than IgE-RI (2*103 SQ-U/ml). The ranges of allergen detection limits for the Mab-ELISA were equal for cat and Derm. pter. (10 – 102 SQ-U/ml). The range of allergen detection limits for CCIE, assaying dog were 104− 105 SQ-U/ml. The ranges of allergen detection limits for HR were equal for eat and Derm. pter. (10 – 102 SQ-U/ml), and 102− 103 SQ-U/ML for dog. Because of cross-reactivity, a minor degree of interference was observed in the IgE-RI and the HR test for the highest concentration of cat and dog allergens.

Notes: The purpose of this study was to evaluate the application of a microdialysis technique for measurement of interstitial histamine levels in intact human skin. Three allergic subjects were investigated. Single dialysis fibers were glued to nylon tubings and inserted in forearm skin by means of a fine cannula. Dialysis fibers were inserted in triplicate and perfused with isotonic saline at a rate of 3 μl/min. After a period of 2 h a 60-μl base-line period was established. Then the patients were skin prick tested (SPT) with allergen in duplicate and a single saline control. Dialysate was collected in consecutive 30 μl fractions. Histamine concentration in the dialysate was analyzed with a glass fiber fluorescence assay. Median base-line histamine level was 4 (range 4–7) ng/ml. Following allergen SPT, dialysate histamine concentration increased to 81 ng/ml (74–128), with maximum values 10–20 min after SPT. Intraindividual coefficient of variation on peak histamine levels was 18.9%. No histamine increase was seen following saline SPT. We consider microdialysis to be a valuable method for assessment of allergic mechanisms in intact human skin.

Notes: Forty-six adult asthmatics allergic to D. pteronyssinus (Dp) participated in a 2-year study. Thirty-one underwent hyposensitization (HS-group). Fifteen were treated with Dp-extract (Dp-group), and 16 with a similar extract modified by monomethoxypolyethylene glycol with reduced allergenicity (mPEG-Dp-group). Fifteen patients served as controls. Dp-specific antibodies and histamine release from blood basophils were determined and compared with Dp-sensitivity in lungs and skin. In addition, IgG and IgE against the major allergen Der p I were followed in a subgroup. Dp-specific IgG, IgG., and IgG4 increased significantly in both HS-treated groups after 1 and 2 years (median; 2.5- to 11.6-fold). IgG4 was not induced if maintenance dose during the first year was less than 20,000 BU. Median skin sensitivity decreased 4.4- to 8.2-fold after 1 year and 7.4- to 21.4-fold after 2 years. Der p I specific IgG response was unrelated to the occurrence or change in IgE with the same specificity. The mPEG-Dp-extract tended to have less effect on skin sensitivity and immunological parameters, differences reaching statistical significance for skin sensitivity only. In the HS-group, the decrease in bronchial sensitivity was significantly correlated to a decrease in IgE (r = 0.36), IgG1/IgG4 (r = 0.49), Dp-specific histamine release (r = 0.58), and to an increase in Dp-specific IgG, (r =−0.36) and IgG4/IgE (r =−0.48). In patients improving clinically. Dp-specific IgG4/IgE increased, and median Dp-specific IgE was reduced to 80 % compared with an increase to 150–160% seen in the unchanged or deteriorated group (P 〈 0.05). Findings indicate an improvement of effect, if the allergen dose is sufficient to reduce specific IgE and/or induce an IgG and especially IgG4 response.

Notes: Cord blood cells were incubated (passively sensitized) with sera from 27 patients with previous systemic reactions to insect stings. Histamine release (HR) from these cells was measured following exposure to venom extracts at increasing concentrations. The aim was to see whether this parameter could predict more efficiently than RAST and skin test the outcome of a subsequent re-sting. Results showed that HR from passively sensitized cells tended to reflect skin sensitivity and specific IgE levels. If patients were not re-stung during the follow-up period, HR from the passively sensitized cells frequently decreased whereas an increase was seen (in 6/13) when using sera collected after re-sting. In conclusion HR from passively sensitized cord blood cells could not satisfactorily predict re-sting reactions in the serum donors.

Notes: The ability of skin prick test (SPT) and histamine release from basophils (HR) to diagnose clinical type I allergy to egg and milk was investigated as compared with double-blind, placebo-controlled food challenge (DBPCFC) in 17 adults suspected of type I egg and/or milk allergy. In both SPT and HR, commercial allergen extracts commonly used for SPT were compared with fresh, standardized foods. With commercial extracts the overall sensitivities of SPT and HR were 0.75 and 0.56 respectively, and none of the tests showed concordance with DBPCFC. With fresh, standardized foods the overall sensitivities of SPT and HR were 1.00 and 0.89 respectively, and both tests now showed a significant concordance with DBPCFC (P〈0.05). Specificity was only slightly improved in SPT, and unchanged in HR. Thus, the use of fresh, standardized foods significantly improved the outcome of both tests, as regards to sensitivity and concordance with DBPCFC. The diagnostic ability of SPT and HR appear to be strongly influenced by the allergen quality.

Notes: This article contains a summary discussion of human health effects linked to indoor air pollution (UP) in homes and other non-industrial environments. Rather than discussing the health effects of the many different pollutants which can be found in indoor air, the approach has been to group broad categories of adverse health effects in separate chapters, and describe the relevant indoor exposures which may give rise to these health effects.The following groups of effects have been comdered: effects on the respiratory system; allergy and other effects on the immune system; cancer and effects on reproduction: effects on the skin and mucous membranes in the eyes, nose and throat; sensory effects and other effects on the nervous system; effects on the cardiovascular system; systemic effects on the liver, kidney and gastro-intestinal system. For each of these groups, effects associated with IAP the principal agents and sources, evidence linking IAP to the effects, susceptible groups, the public health relevance, methods for assessment, and major research needs are briefly discussed.For some groups of effects, clear relationships with exposure to IAP have been reported in the world literature. Among these are respiratory disease (particularly among children), allergy (particularly to house dust mites) and mucous membrane irritation (particularly due to formaldehyde). Large numbers of people have been, and are still being affected.Many chemicals encountered in indoor air are known or suspected to cause sensory irritation or stimulation. These, in turn, may give rise to a sense of discomfort and other symptums cummonly reported in so-called “sick” buildings. Camplex mixtures of organic chemicals in indoor air also have the potential to invoke subtle effects on the central and peripheral nervous system, leading to changes in behaviour and performance.An increased risk of developing lung cancer has been linked to exposure to environmental tobacco smoke (ETS) and to radon decay products. Lung cancer is a very serious disease with a high fatality rate; however, the number of people affected is much lower than the number of people contracting resparatory disease or alhgies, or experiencing irritative effects due to exposure to indoor pollution.The effects of IAP on reproduction, cardiovascular disease and on other systems and organs have not been well documented to date. To a certain extent, this may mean that no serious effects occur, but there has been little by way of research to clearly document the absence of these tvpes of effects.

Notes: Floor dust from nine city hall office buildings was separated into fiber and particulate fractions and analyzed for volatile organic compounds (VOCs) and total VOC (TVOC) by thermal desorption/high resolution gas chromatography (HRGC). Components were identified by HRGC/mass spectroscopy (MS). Principal component analysis was applied to VOC emission profiles revealing similarities between buildings and correlations between profiles and SBS symptoms of mucous membrane irritation and “concentration difficulty”. While the dominant pattern in emission profiles was not correlated with SBS irritation complaints, partial least squares analysis in latent variables (PLS analysis) identified VOCs for which peak areas were correlated with SBS irritation complaints and the CNS Complaint, “concentration difficulty”

Notes: Microbial content in dusts such as bacteria, endotoxins and fungal spores are thought to be important causative agents for the symptoms in organic dust-related diseases. Micro-organism-induced mediator release was therefore examined in human cells. Bacteria were found to trigger the release of histamine and leurotriene B4 from bronchoalveolar cells, and in suspensions of dispersed lung and tonsillar cells they induce the release of histamine and prostaglandin D2. Basophil histamine release was triggered by both bacteria and their endotxins. Furthermore, histamine release caused by allergic as well as non-allergic reactions was enhanced by bacteria, endotoxins and fungal spores of mould. These effects of dust components may be crucial for the symptoms in q a n i c dust-related diseases, since the mediators are of key importance to the broncho-obstructive and inflammatory events in these disorders.

Notes: A microfiberglass-based histamine assay (HRM) was compared with an automated flourometric histamine assay (HRA). Twenty-four with and 24 without a case history (CH) of milk and/or egg allergy were tested by HRM and HRA, skin prick test (SPT), and specific serum IgE (RAST). Six different concentrations of milk, egg, and anti-IgE to stimulate washed leukocytes (250 μ for HRA and whole blood samples (25 μ for HRM) in parallel. When we compared scores representing basophil senditivity, correlation coefficients (rs) were positive (r(anti-IgE))=0.88, r(egg) = 0.95, r(milk) = 0.88, P〈 0.001), but no significant correlation were found after found after exclusion of the negatives in both tests. In some individual dose-response curves, the scores obtained by HRM were shifted to higher allergen and anti-IgE concentrations. A high degree of concordance was found in positive and negative responses between the two: anti-IgE 91%, egg 92%, milk 86%. Finally, we found a good concordance between, on one other, CH, SPT, and RAST (HRM vs. CH/SPT/RAST) 92/82/82%; milk 89/74/67%. We conclude that HRM is in good qualitative, but poor quantitative, agreement with the autoanalyzer-based fluorometric histamine assay.