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Notes: Abstract A theory of the effect of turbulence on the response of static pressure probes is given. To apply it to a given probe, the response in a laminar stream must be known as a function of orientation. Results are reported for Prandtl probes. For these the effect of turbulence is negligible at the levels encountered in pipe flows, but is highly significant at those prevailing in jets and other strongly turbulent systems. Experimental verification is given and the effect of turbulence length scale is demonstrated.

Notes: Background Increased production of IL-4 and IL-5 and decreased production of IFN-γ by CD4+ T cells has been implicated in asthma pathogenesis. However, CD8+ T cells also produce type 1 and type 2 cytokines and the relative roles of CD4+ and CD8+ T cell cytokine production in asthma have not been previously studied.Objective To determine the production of the type 1 and type 2 cytokines by CD4+ and CD8+ T cell subsets in asthmatic and normal subjects.Methods Intracellular cytokine staining for IL-4, -5, -10, -13 and IFN-γ was analysed in peripheral blood CD4+ and CD8+ T cells from 24 atopic asthmatic and 20 normal subjects.Results Both subsets of T cells produced all cytokines studied and there were no significant differences between CD4+ and CD8+ T cells in their capacity to produce either type 1 or type 2 cytokines. There were significantly increased frequencies of IFN-γ-positive CD4+ (13.1 ± 2.4%, vs. 7.3 ± 1.4%) and CD8+ (20.0 ± 2.9%, vs. 9.6 ± 2.1%) T cells in asthmatic subjects compared with normal subjects (P 〈 0.05), but not in frequencies of CD4+ or CD8+ T cells staining positively for IL-4, -5, -10 or -13.Conclusion The frequencies of peripheral blood CD8+ T cells producing type 1 and type 2 cytokines are comparable with the frequencies of CD4+ T cells. There was an increased frequency of IFN-γ producing CD4+ and CD8+ T cells in asthmatic compared with normal subjects. Further studies investigating T cells derived from the airways and investigating various stages within the disease process are required to further elucidate the importance of type 2 and type 1 T cell cytokine production in the pathogenesis of human allergic disease.

Notes: Background Recent investigation has revealed that spider mites such as Tetranychus urticae and Panonychus ulmi are important allergens in the development of occupational asthma among apple farmers.Objective To evaluate IgE binding components in T. urticae and P. ulmi-derived crude extracts and their cross-reactivity with Panonychus citri, Tyrophagus putrescentiae and Dermatophagoides pteronyssinus in apple cultivating farmers.Methods Thirty-one apple farmers with positive skin responses to T. urticae or P. ulmi were randomly recruited, and specific IgE levels in their sera were measured using ELISA. Cross-reactivity was evaluated by ELISA inhibition. IgE binding components were evaluated by IgE immunoblotting.Results A total of 11 IgE binding components in T. urticae and 10 in P. ulmi were found. Among them, the 17 kDa, 27 kDa, 33 kDa, 37 kDa, 41 kDa, 56 kDa, and 75 kDa allergens in T. urticae, and the 33 kDa, 41 kDa, and 51 kDa allergens in P. ulmi were identified as dominant allergens. T. urticae-specific IgE binding was completely inhibited by 100 μg/mL of T. urticae (99.7%), but only partially inhibited by P. citri (83.0%), P. ulmi (71.6%), T. putrescentiae (69.7%), and D. pternonyssinus (60.1%). P. ulmi-specific IgE binding was completely inhibited by additions of P. citri (92.3%) and P. ulmi (91.2%), but only partially inhibited by the addition of T. urticae (61.5%), T. putrescentiae (57.7%), and D. pteronyssinus (54.4%).Conclusion There were seven dominant allergens found in T. urticae and three in P. ulmi. T. urticae- and P. ulmi-specific IgE bindings were partially inhibited by crude extracts derived from D. pteronyssinus and T. putrescentiae.

Notes: Specific IgE responses to allergens provide useful models for evaluating the genetic factors that control human immune responses. A recent survey demonstrated that the citrus red mite (Panonychus citri, CRM) is the most important allergen in the development of asthma in citrus farmers.〈section xml:id="abs1-2"〉〈title type="main"〉ObjectiveThe aim of this study was to evaluate whether susceptibility or resistance to CRM-induced asthma was associated with HLA-DRB1 gene.〈section xml:id="abs1-3"〉〈title type="main"〉MethodsDNAs were extracted from two groups of unrelated Korean adults living around citrus farms: (1) Ninety-one adults with CRM-sensitive asthma; and (2) 98 exposed, healthy nonatopic controls. Genotypes of HLA-DRB1 alleles were carried out using PCR-based methods.〈section xml:id="abs1-4"〉〈title type="main"〉ResultsAllelic frequency of HLA-DRB1*07 was higher in the CRM-sensitive asthmatics compared to the controls (17.6% vs 4.1%, Pc = 0.01). Conversely, the frequency of DRB1*04 was lower in the CRM-sensitive asthmatics compared to the controls (19.8% vs 40.8%, Pc = 0.01). No significant difference was found in the distributions of the other HLA-DRB1 gene-encoded antigens between the two groups.〈section xml:id="abs1-5"〉〈title type="main"〉ConclusionHLA-DRB1 genes may be involved in the development of CRM-induced asthma. In addition, HLA-DR7 may increase, and DR4 decrease, the risk of developing the asthma in CRM-exposed adults.

Notes: Several candidate genes have been reported to be linked to intermediate phenotypes of asthma in Caucasian populations.To evaluate linkage between phenotypes of asthma and gene markers of high affinity IgE receptor-β gene (D11S97), IL-4 cytokine gene cluster (IL-4R1), and T-cell receptor α/δ gene complex (D14S50) in Korean nuclear families.Nuclear families (127 probands and their 130 siblings) for the linkage analysis were ascertained through asthmatic children. Linkages between total serum IgE response, skin responses to common aeroallergens, and bronchial responsiveness to methacholine were performed using a sib-pair approach.The square difference of the slope of the dose–response curve (DRS) between sib-pairs with two IL-4R1 identical alleles was smaller than with one or with neither IL-4R1 identical allele (P = 0.004). As for D14S50, the differences of DRS between sib-pairs with two identical alleles and with one identical allele were smaller than with neither identical alleles (P = 0.01). As for D11S97, no significant differences were observed among the groups with identical alleles of two, one or zero. With regard to total serum IgE levels, no significant linkage was found between this phenotype and the above three gene markers. As for skin responses to common aeroallergens, significant evidence was obtained to establish a linkage between this phenotype and the marker IL-4R1 (P = 0.01). However, no significant linkage was found between this phenotype and the markers D11S97 and D14S50.The expression of bronchial responsiveness to methacholine may be influenced by genetic factors in the IL-4 cytokine gene cluster and/or T-cell receptor α/δ gene complex, but the genetic influence of the FcεRI-β gene may be minimal in the expression of bronchial responsiveness in Korean nuclear families.

Notes: Background With β-agonists being the most widely used agents in the treatment of asthma, in vitro studies reported that β2-adrenergic receptor (ADRB2) polymorphisms are associated with agonist-promoted down-regulation.Objective The present population-based study aimed to evaluate the association between bronchodilating response to inhaled short-acting β-agonist and two non-synonymous single-nucleotide polymorphisms (SNPs) of ADRB2 (ADRB2-16 and ADRB2-27).Methods Two hundred and nine children with reduction in forced expiratory volume in 1 s of more than 20% on methacholine bronchial challenge underwent bronchodilating response testing 5 min after the inhalation of 200 μg of albuterol. Of these 209, 195 gave peripheral blood for genotyping of ADRB2 polymorphisms.Results The bronchodilating response was significantly higher in subjects with the homozygous Arg16 than in those with the homozygous Gly16. It was further demonstrated that haplotype pairs of the homozygous Arg16Gln27 and of the heterozygous Arg16Gln27/Gly16Glu27 showed the highest bronchodilating responses, and the haplotype pairs of the homozygous Gly16Gln27 the lowest response. As a whole, the bronchodilating response was more positively associated with the combined quantity of Arg16 and Glu27 polymorphisms than with that of Arg16 alone.Conclusion Non-synonymous SNPs of ADRB2 at codons 16 and 27 is significantly associated with bronchodilating response to inhaled short acting β-agonists.

Notes: Background  Our previous work on linkage analysis showed that histamine release from basophils to anti-IgE stimuli was linked to the gene marker of chromosome 11q13, where the β chain of the high-affinity receptor for IgE (FcεRI-β) is located.Objective  To evaluate the association between FcεRI-mediated histamine release from basophils and four bi-allelic single nucleotide polymorphisms of the FcεRI-β gene.Methods  Phenotypes of asthma, such as maximal histamine release from basophils and atopy, were measured from 80 randomly recruited asthmatic children. Polymorphisms of the FcεRI-β gene were determined by PCR-based methods.Results  The polymorphism in exon 7, resulting in Glu to Gly substitution, was significantly associated with histamine release from basophils to anti-IgE stimuli, but not with total IgE levels and skin test responses to aeroallergens.Conclusion This study supports a role for the FcεRI-β gene in the expression of high affinity IgE receptor-mediated histamine release from basophils.

Notes: Background In most epidemiological survey studies, only subjective symptoms and past medical history of asthma have been used as diagnostic criteria. Even though a questionnaire survey can be performed in a large population study at low cost, limitations such as lack of objectivity and poor predictability in non-specific bronchial hyperresponsiveness cannot be avoided.Objectives The purpose of this study was to elucidate the prevalence of current asthma based on questionnaires and methacholine bronchial provocation test, and the prevalence of atopy in Korea.Methods We performed modified ATS respiratory questionnaires and allergen skin-prick test with 10 common inhalant allergens among 3219 subjects aged 7–19 years in Seoul and a rural part of a small city, Chungju in Korea. Methacholine bronchial provocation tests were also performed among those who had asthma symptoms according to the questionnaire. The criteria of asthma was presence of both asthma symptoms and non-specific bronchial hyperresponsiveness. Atopy was defined as when an allergen induced weal size is same or larger than that caused by histamine.Results The prevalence of asthma based on questionnaires and methacholine bronchial provocation tests was 4.6%, while the prevalence of wheeze was 8.2% and 19.3% of total population complained of one or more respiratory symptoms related to asthma on the questionnaires. There was no significant difference according to age, sex and living area. The mean prevalence of atopy was 35.0% and the most common allergens were Dermatophagoides farinae (30.9%), Dermatophagoides pteronyssinus (27.5%), cat fur (20.4%) and cockroach (11.8%). The atopy prevalence in Chungju area was higher than that in Seoul and males showed a higher prevalence than females. The asthma prevalence was higher among atopies (6.8%) than among non-atopies (2.7%). None of questionnaire items were enough to predict the presence of bronchial hyperresponsiveness in terms of sensitivity, specificity and positive predictive value.Conclusion The prevalence rate of current asthma in Korea was 4.6% and the prevalence rate of atopy in Korea was 35.0%. Questionnaire-based surveys are not enough to predict the actual prevalence of asthma.