Development Of Bronchial Hyperresponsiveness Research Articles

Interaction of the TLR4 rs1927911 polymorphism with house dust mite sensitization in allergic rhinitis with its prognosis.

Sensitization to the house dust mite (HDM) plays important roles in the development of allergic rhinitis (AR). Toll-like receptor 4 (TLR4) is a key initiator of the innate immune system upon exposure to environmental factors. The present study investigated the independent and interaction effects of HDM sensitization and TLR4 rs1927911 polymorphism on AR and its prognosis in children. This study included 2,929 children (mean age, 7.8 yrs) from the Children's HEalth and Environmental Research study (CHEER), a prospective study with a 2-year-interval for 4 years. An ISAAC questionnaire was used with skin prick tests in all subjects. TaqMan genotyping was performed for TLR4 (rs1927911) polymorphism in 1,024 children. HDM sensitization increased risk of current AR (aOR, 2.50; 95% CI, 1.41-4.41; P for interaction = 0.005), current asthma at follow-up (aOR, 4.63; 95% CI, 2.41-8.88; P for interaction < 0.001) and allergic march (aOR, 2.57; 95% CI, 1.06-6.22; P for interaction = 0.002) by interacting with genotypes of TLR4 (rs1927911). HDM sensitization increased risk of persistence (aOR, 4.17; 95% CI, 1.77-9.83) and new diagnosis of AR (aOR, 2.48; 95% CI, 1.10-5.61), new sensitization to inhalant allergens (aOR, 10.67; 95% CI, 5.83-19.54), and new development of bronchial hyper-responsiveness (aOR, 5.29; 95% CI, 2.29-12.21) in children with CC genotype of TLR4 rs1927911. HDM sensitization affects AR and its prognosis by interacting with TLR4 rs1957911 polymorphism. The preventive and therapeutic strategies for AR in children need to be targeted in accordance with genetic susceptibility with HDM sensitization.

Retraction.

Retraction: "The role of HOTAIR-induced downregulation of microRNA-126 and interleukin-13 in the development of bronchial hyperresponsiveness in neonates," by Dong-Mei Wu, Zi-Hui Zheng, Shan Wang, Xin Wen, Xin-Rui Han, Yong-Jian Wang, Min Shen, Shao-Hua Fan, Zi-Feng Zhang, Qun Shan, Meng-Qiu Li, Bin Hu, Yuan-Lin Zheng, Gui-Quan Chen, Jun Lu, J Cell Physiol. 2019; 16400-16411: The above article, published online on 21 February 2019 in Wiley Online Library (https://onlinelibrary.wiley.com/doi/full/10.1002/jcp.28309), has been retracted by agreement between the journal's Editor in Chief, Prof. Dr. Gregg Fields, and Wiley Periodicals LLC. The retraction has been agreed after Gui-Quan Chen stated to be listed as a coauthor despite qualification for contributorship was not fulfilled. An investigation revealed several flaws and inconsistencies between results presented and experimental methods described were found, and so the editors consider the conclusions of this article to be invalid. The authors were not available for a final confirmation of the retraction.

Allergic sensitization pattern as amarker of bronchial hyperresponsiveness in allergic rhinitis patients living in temperate continental climate zone.

Bronchial hyperresponsiveness (BHR) is akey feature of asthma, but it may also appear in allergic rhinitis. The type of allergen, as well as regional characteristics, play an important role in the development of BHR. The aim of our study was to analyze allergen sensitization patterns and the factors that affect BHR in allergic rhinitis patients living in temperate continental climate zone. This study retrospectively analyzed allergic rhinitis patients from Eastern Slovakia who underwent skin-prick tests to aeroallergens, spirometry, histamine and methacholine bronchial provocation tests for evaluation of lower airway symptoms. We analyzed the associations between BHR and the pattern of aeroallergen sensitization, lung function parameters, and the total IgE and eosinophil levels. Out of 365 allergic rhinitis patients (age range 16-64years), 114 showed BHR. Sensitization to house dust mites (HDMs) and grass were the most common. BHR was significantly associated with sensitization to dogs (odds ratio, OR = 2.15, 95% confidence interval, CI: 1.13-4.11) and Alternaria (OR = 2.15, 95% CI: 1.06-4.35); however, BHR did not show arelationship with HDMs sensitization. The levels of total IgE and eosinophils were higher in the BHR-positive group. Sensitization to more than six allergens significantly increased the probability of BHR (p < 0.01). Dogs and Alternaria, but not HDMs, were the sensitizing agents most closely associated with BHR. High-grade sensitization and increased total IgE and eosinophil levels were characteristic clinical signs in BHR-positive allergic rhinitis patients in the temperate continental climatic zone.

Retracted: The role of HOTAIR-induced downregulation of microRNA-126 and interleukin-13 in the development of bronchial hyperresponsiveness in neonates.

Long noncoding RNAs, including HOTAIR, are involved in the pathogenesis of a wide range of diseases. This study aimed to explore the mechanism underlying the involvement of HOTAIR in neonatal bronchial hyperresponsiveness (BHR). A total of 105 newborns were recruited in this study to collect their peripheral blood mononuclear cell and serum samples, which were then divided into different genotype groups based on the genotypes of rs4759314, rs874945, and rs7958904. The real-time polymerase chain reaction, western blot analysis, computational analyses, and luciferase assays were performed to establish the regulatory relationships between the HOTAIR, microRNA-126 (miR-126), and interleukin-13 (IL-13). The level of HOTAIR, miR-126, and IL-13 among rs4759314 AA, AG, and GG groups, as well as among rs874945 GG, AG, and AA groups was similar. However, the level of HOTAIR was increased in the rs7958904 GG group, accompanied by a decreased level of miR-126 and IL-13. In addition, the level of airway responsiveness was comparable among rs4759314 AA, AG, and GG groups, as well as among rs874945 GG, AG, and AA groups. However, the airway responsiveness in the groups rs7958904 CG and CC was much stronger than that of the GG group. We also demonstrated that, by directly binding to miR-126, HOTAIR reduced the expression of miR-126, which in turn decreased the expression of IL-13. In summary, we demonstrated the role of HOTAIR-induced downregulation of miR-126 and IL-13 in the development of BHR in neonates.

Fractional Exhaled Nitric Oxide (FeNO) in the Screening and Diagnosis Work-Up of Occupational Asthma

FeNO is a simple non-invasive tool used as a surrogate marker of airway inflammation in the management of asthma. FeNO has been assessed in several populations of workers exposed to high- and low-molecular weight agents. However, there are many confounding factors to consider in the interpretation of FeNO. As such, its use in the investigation of occupational asthma (OA) has yielded inconsistent results. In screening studies of OA to high molecular weight (HMW) agents, an increase of FeNO over time has been associated with the development of bronchial hyperresponsiveness (BHR). When used in the investigation of OA, increases in FeNO show high positive predictive values for a positive specific inhalation challenge (SIC) to HMW agents. Subjects with high specific IgE to their workplace allergens seem to present higher increases in FeNO than subjects without specific IgE to causal agent. Changes in FeNO have less frequently been observed in studies of OA to low molecular weight (LMW) agents than OA to HMW agents, except for isocyanate-induced OA. Cluster analyses of patients exposed to various HMW and LMW agents have documented significant increases of FeNO in clusters of patients with OA to HMW agents, but not LMW. Recent studies have provided useful information for improving our understanding of the pathophysiology of exhaled NO in OA despite the previously reported conflicting results. Future studies are still required to clarify its role in the screening, investigation, and management of OA.

A single nucleotide polymorphism in hsa‑miR‑146a is responsible for the development of bronchial hyperresponsiveness in response to intubation during general anesthesia.

Bronchial hyperresponsiveness (BHR) is the most common clinical manifestation identified in asthmatic patients, and intubation is the major factor that stimulates the airway of patients receiving general anesthetic. In the present study, nitric oxide synthase1 (NOS1) was identified as a target gene of micro (mi)R‑146a using insilico analysis and luciferase assay. Furthermore, the regulatory role of miR‑146a was demonstrated by the observation that the NOS1 expression level in pulmonary artery smooth muscle cells (PASMCs) transfected with miR‑146a mimics was significantly downregulated and the NOS1 expression level in PASMCs transfected with miR‑146a inhibitors was significantly upregulated. Additionally, it was identified that a polymorphism in pri‑miR‑146 interfered with mature processing and reduced the quantity of mature miRNA. To assess the association between the polymorphism and the development of BHR,563 patients with basic pulmonary diseases, such as asthma, emphysema or bronchitis were enrolled in the present study. Each participant received a general anesthetic and the development of BHR was evaluated. The miR‑146a rs2910164 polymorphism CC genotype was identified to be significantly associated with a decreased risk of BHR in response to intubation when compared with the GG or GC genotype (odds ratio,0.38; confidence interval, 0.18‑0.78). These findings indicate that the miR‑146a rs2910164 polymorphism is associated with a decrease risk of BHR, and the CC genotype increased the level of NOS1 expression, which was physiologically inhibited by wild‑type miR‑146a.

Th9 cells elicit eosinophil-independent bronchial hyperresponsiveness in mice

BackgroundAirway accumulation of eosinophils and bronchial hyperresponsiveness (BHR) are prominent features of bronchial asthma, though the contribution of eosinophils to the development of BHR is controversial. Similar to Th2 cell-mediated pathology, Th9 cells, characterized by IL-9-producing activity, have been demonstrated to induce airway eosinophilia and BHR. In this study, we investigated the role of eosinophils in Th9-mediated BHR by employing Th9 cell-transferred murine airway inflammation model. MethodsOvalbumin (OVA)-specific Th2 and Th9 cells were differentiated from CD4+ T cells of DO11.10/RAG-2−/− mice in vitro and cytokine-producing activity of those cells was examined. BALB/c mice were adoptively transferred with Th2 or Th9 cells and challenged with OVA. Then, the number of inflammatory cells in bronchoalveolar lavage fluid and bronchial responsiveness to inhaled methacholine were determined. ResultsBoth in Th2 and Th9 cell-transferred mice, substantial accumulation of eosinophils in the lungs and BHR were induced by challenge with specific antigen. Nevertheless, an essential and dispensable role of eosinophils in Th2- and Th9-mediated BHR, respectively, was demonstrated by employing eosinophil-deficient mice. The neutralization of IL-9 as well as deficiency of IL-10 in the donor cells did not affect Th9-mediated BHR. ConclusionsIn contrast to Th2-mediated and eosinophil-dependent BHR, Th9 could induce BHR independently from eosinophils and its characteristic cytokines, IL-9 and IL-10.

Reslizumab: First Global Approval.

Reslizumab (Cinqair(®)) is a humanised monoclonal interleukin-5 (IL-5) antibody developed by Teva that has been approved in the USA for patients aged ≥18years as add-on maintenance treatment for severe asthma with an eosinophilic phenotype. IL-5 stimulates the production, activation and maturation of eosinophils and is therefore thought to play a role in the development of bronchial hyper-responsiveness. This article summarizes the milestones in the development of reslizumab leading to this first approval for add-on maintenance treatment of severe asthma with an eosinophilic phenotype.

Atopic dermatitis phenotype with early onset and high serum IL-13 is linked to the new development of bronchial hyperresponsiveness in school children.

Atopic dermatitis (AD) is characterized by a heterogeneous clinical spectrum, and some forms of AD are associated with the initial steps of allergic march. The aims of this study were to determine AD phenotypes in school-age children and investigate their associations with the allergic march in each cluster. We included 242 children (6-8 years) with current AD from the Children's HEalth and Environmental Research study, a 4-year prospective follow-up study with 2-year survey intervals. Latent class analysis was used. Serum IL-13 and thymic stromal lymphopoietin (TSLP) levels at the time of enrollment were measured using ELISA. We identified four current AD phenotypes in children, characterized as 'early onset with low atopy' (26.4% of the sample; group 1), 'early onset with high atopy and high eosinophil percentages' (48.3%; group 2), 'late onset with low atopy' (9.9%; group 3), and 'late onset with high atopy and normal eosinophils' (15.3%; group 4). Although groups 2 and 4 demonstrated high atopic burden, children in group 2 showed the persistence of AD and eosinophilia associated with a high prevalence of new cases of bronchial hyper-responsiveness and asthma symptoms during follow-up. The serum IL-13 level was significantly increased in the early-onset AD groups, but there was no significant difference in the serum TSLP levels across all four groups. An allergic march-associated AD phenotype exists that is characterized by early onset of AD with its persistence, increased serum IL-13 levels, high atopy, and a persistently increased blood eosinophil percentage.

Trigger of bronchial hyperresponsiveness development may not always need eosinophilic airway inflammation in very early stage of asthma.

Background:Cough variant asthma (CVA), a suggested precursor of standard bronchial asthma (SBA), is characterized by positive bronchial hyperresponsiveness (BHR) and a chronic cough response to bronchodilator that persists for >8 weeks.Objective:Airway inflammation, BHR, and airway obstructive damage were analyzed to assess whether CVA represents early or mild-stage SBA.Methods:Patients with newly diagnosed CVA (n = 72) and SBA (n = 84) naive to oral or inhaled corticosteroids and without exacerbated asthma were subjected to spirometry, impulse oscillometry, BHR tests, sputum induction, and fractional exhaled nitric oxide measurements.Results:In the patients with CVA, spirometry demonstrated higher forced expiratory volume in 1 second (FEV1) to forced vital capacity ratio, FEV1 percent predicted, flow volume at 50% of vital capacity % predicted, and flow volume at 25% of vital capacity % predicted values, and impulse oscillometry demonstrated lower R5–Z20, AX, and Fres, and higher X5 values. In addition, the fractional exhaled nitric oxide and sputum eosinophil numbers were lower and the PC20 was higher than in patients with moderate SBA. However, these factors were similar in the patients with CVA and in the patients with intermittent mild SBA. A significantly smaller proportion of the patients with CVA had increased sputum eosinophils than the patients with intermittent mild SBA (p < 0.0001). However, interestingly, among the patients with CVA, no significant differences in the PC20 values were found between the patients with and those without increased sputum eosinophils.Conclusions:All measures of central and peripheral airway obstruction, eosinophilic inflammation, and airway hyperresponsiveness in patients with CVA were milder than in patients with moderate SBA but were similar to those of patients with intermittent mild SBA. In CVA, the BHR was not affected by airway eosinophilic inflammation, which indicated that the very early development of BHR may not always need airway eosinophilic inflammation.

Sensitization by subcutaneous route is superior to intraperitoneal route in induction of asthma by house dust mite in a murine mode.

ABSTRACTObjective To develop a new experimental model of chronic allergic pulmonary disease induced by house dust mite, with marked production of specific immunoglobulin E (IgE), eosinophilic inflammatory infiltrate in the airways and remodeling, comparing two different routes of sensitization.Methods The protocol lasted 30 days. BALB/c mice were divided into six groups and were sensitized subcutaneously or intraperitoneally with saline (negative control), Dermatophagoides pteronyssinus (Der p) 50 or 500mcg in three injections. Subsequently they underwent intranasal challenge with Der p or saline for 7 days and were sacrificed 24 hours after the last challenge. We evaluated the titration of specific IgE anti-Der p, eosinophilic density in peribronchovascular space and airway remodeling.Results Both animals sensitized intraperitoneally and subcutaneously produced specific IgE anti-Der p. Peribronchovascular eosinophilia increased only in mice receiving lower doses of Der p. However, only the group sensitized with Der p 50mcg through subcutaneously route showed significant airway remodeling.Conclusion In this murine model of asthma, both pathways of sensitization led to the production of specific IgE and eosinophilia in the airways. However, only the subcutaneously route was able to induce remodeling. Furthermore, lower doses of Der p used in sensitization were better than higher ones, suggesting immune tolerance. Further studies are required to evaluate the efficacy of this model in the development of bronchial hyperresponsiveness, but it can already be replicated in experiments to create new therapeutic drugs or immunotherapeutic strategies.

Bronchial hyperresponsiveness decreases through childhood

Limited knowledge exists about development of bronchial hyperresponsiveness (BHR) through adolescence. We aimed to assess changes in and risk factors for BHR in adolescence. From a Norwegian birth cohort 517 subjects underwent clinical examinations, structured interviews and methacholine challenges at age 10 and 16. BHR was divided into four categories: no BHR (cumulative methacholine dose required to reduce FEV(1) by 20% (PD(20)) >16 μmol), borderline BHR (PD(20) ≤16 and >8 μmol), mild to moderate BHR (PD(20) ≤8 and >1 μmol), and severe BHR (PD(20) ≤ 1 μmol). Logistic regression analysis was used to assess risk factors and possible confounders. The number of children with PD(20) ≤ 8 decreased from 172 (33%) to 79 (15%) from age 10-16 (p < 0.001). Most children (n = 295, 57%) remained in the same BHR (category) from age 10-16 (50% with no BHR), whereas the majority 182 (82%) of the 222 children who changed BHR category, had decreased severity at age 16. PD(20) ≤ 8 at age 10 was the major risk factor for PD(20) ≤ 8 6 years later (odds ratio 6.3), without significant confounding effect (>25% change) of gender, active rhinitis, active asthma, height, FEV(1)/FVC, or allergic sensitization. BHR decreased overall in severity through adolescence, was stable for the majority of children and only a minority (8%) had increased BHR from age 10 to 16. Mild to moderate and severe BHR at age 10 were major risk factors for PD(20) ≤ 8 at 16 years and not modified by asthma or body size.

Sildenafil decreases rat tracheal hyperresponsiveness to carbachol and changes canonical transient receptor potential gene expression after antigen challenge

Inhibition of type-5 phosphodiesterase by sildenafil decreases capacitative Ca2+ entry mediated by transient receptor potential proteins (TRPs) in the pulmonary artery. These families of channels, especially the canonical TRP (TRPC) subfamily, may be involved in the development of bronchial hyperresponsiveness, a hallmark of asthma. In the present study, we evaluated i) the effects of sildenafil on tracheal rings of rats subjected to antigen challenge, ii) whether the extent of TRPC gene expression may be modified by antigen challenge, and iii) whether inhibition of type-5 phosphodiesterase (PDE5) may alter TRPC gene expression after antigen challenge. Sildenafil (0.1 µM to 0.6 mM) fully relaxed carbachol-induced contractions in isolated tracheal rings prepared from naive male Wistar rats (250-300 g) by activating the NO-cGMP-K+ channel pathway. Rats sensitized to antigen by intraperitoneal injections of ovalbumin were subjected to antigen challenge by ovalbumin inhalation, and their tracheal rings were used to study the effects of sildenafil, which more effectively inhibited contractions induced by either carbachol (10 µM) or extracellular Ca2+ restoration after thapsigargin (1 µM) treatment. Antigen challenge increased the expression of the TRPC1 and TRPC4 genes but not the expression of the TRPC5 and TRPC6 genes. Applied before the antigen challenge, sildenafil increased the gene expression, which was evaluated by RT-PCR, of TRPC1 and TRPC6, decreased TRPC5 expression, and was inert against TRPC4. Thus, we conclude that PDE5 inhibition is involved in the development of an airway hyperresponsive phenotype in rats after antigen challenge by altering TRPC gene expression.

Sildenafil decreases rat tracheal hyperresponsiveness to carbachol and changes canonical transient receptor potential gene expression after antigen challenge

Inhibition of type-5 phosphodiesterase by sildenafil decreases capacitative Ca2+ entry mediated by transient receptor potential proteins (TRPs) in the pulmonary artery. These families of channels, especially the canonical TRP (TRPC) subfamily, may be involved in the development of bronchial hyperresponsiveness, a hallmark of asthma. In the present study, we evaluated i) the effects of sildenafil on tracheal rings of rats subjected to antigen challenge, ii) whether the extent of TRPC gene expression may be modified by antigen challenge, and iii) whether inhibition of type-5 phosphodiesterase (PDE5) may alter TRPC gene expression after antigen challenge. Sildenafil (0.1 µM to 0.6 mM) fully relaxed carbachol-induced contractions in isolated tracheal rings prepared from naive male Wistar rats (250-300 g) by activating the NO-cGMP-K+ channel pathway. Rats sensitized to antigen by intraperitoneal injections of ovalbumin were subjected to antigen challenge by ovalbumin inhalation, and their tracheal rings were used to study the effects of sildenafil, which more effectively inhibited contractions induced by either carbachol (10 µM) or extracellular Ca2+ restoration after thapsigargin (1 µM) treatment. Antigen challenge increased the expression of the TRPC1 and TRPC4 genes but not the expression of the TRPC5 and TRPC6 genes. Applied before the antigen challenge, sildenafil increased the gene expression, which was evaluated by RT-PCR, of TRPC1 and TRPC6, decreased TRPC5 expression, and was inert against TRPC4. Thus, we conclude that PDE5 inhibition is involved in the development of an airway hyperresponsive phenotype in rats after antigen challenge by altering TRPC gene expression.

Identification of PCDH1 as a Novel Susceptibility Gene for Bronchial Hyperresponsiveness

Asthma is a chronic inflammatory airway disease that affects more than 300 million individuals worldwide. Asthma is caused by interaction of genetic and environmental factors. Bronchial hyperresponsiveness (BHR) is a hallmark of asthma and results from increased sensitivity of the airways to physical or chemical stimulants. BHR and asthma are linked to chromosome 5q31-q33. To identify a gene for BHR on chromosome 5q31-q33. In 200 Dutch families with asthma, linkage analysis and fine mapping were performed, and the Protocadherin 1 gene (PCDH1) was identified. PCDH1 was resequenced in 96 subjects from ethnically diverse populations to identify novel sequence variants. Subsequent replication studies were undertaken in seven populations from The Netherlands, the United Kingdom, and the United States, including two general population samples, two family samples, and three case-control samples. PCDH1 mRNA and protein expression was investigated using polymerase chain reaction, Western blotting, and immunohistochemistry. In seven out of eight populations (n = 6,168) from The Netherlands, United Kingdom, and United States, PCHD1 gene variants were significantly associated with BHR (P values, 0.005-0.05) This association was present in both families with asthma and general populations. PCDH1 mRNA and protein were expressed in airway epithelial cells and in macrophages. PCDH1 is a novel gene for BHR in adults and children. The identification of PCDH1 as a BHR susceptibility gene may suggest that a structural defect in the integrity of the airway epithelium, the first line of defense against inhaled substances, contributes to the development of BHR.

Smoke exposure interacts with ADAM33 polymorphisms in the development of lung function and hyperresponsiveness

ADAM33 is the first identified asthma gene by positional cloning, especially asthma combined with bronchial hyperresponsiveness (BHR). Moreover, ADAM33 is associated with early-life lung function and decline of forced expiratory volume in 1 s (FEV(1)) in the general population. In utero and postnatal cigarette smoke exposure (CSE) are associated with reduced lung function, and development of BHR and asthma. We hypothesized that this may occur via interaction with ADAM33. To replicate the role of ADAM33 in childhood lung function and development of BHR and asthma. Furthermore, we investigated gene-environment interaction of ADAM33 with in utero and postnatal CSE in the Dutch PIAMA cohort. Six ADAM33 single-nucleotide polymorphisms (SNPs) were genotyped. Rint was measured at age 4 and 8 years, FEV(1) and BHR at age 8 years; asthma was based on questionnaire data at age 8. In the total cohort, the rs511898 A, rs528557 C, and rs2280090 A alleles increased the risk to develop asthma (+BHR). There existed interaction between in utero but not postnatal CSE and the rs528557 and rs3918396 SNPs with respect to development of BHR, the rs3918396 SNP with Rint at age 8 and the rs528557 SNP with FEV(1)% predicted. We confirm associations between ADAM33 and the development of asthma (+BHR). This is the first study suggesting that interaction of in utero CSE with ADAM33 results in reduced lung function and the development of BHR, which needs further confirmation.

The Effect of Thoracosopic Thoracic Sympathetomy on Pulmonary Function and Bronchial Hyperresponsiveness

Background. Endoscopic thoracic sympathectic denervation (ESD) is a procedure used in primary hyperhidrosis and upper extremity ischemia. Bronchial tone is affected by the sympathetic and parasympathetic nervous systems and bronchial asthma is associated with an imbalance between them. The aim of this study was to evaluate the effects of ESD on pulmonary function and bronchial hyperresponsiveness (BHR). Patients and methods. Fifty-eight patients with primary hyperhidrosis (n = 54) or upper limb ischemia (n = 4) were included. Spirometry and bronchial provocation test with methacholine was performed before and 4 weeks after ESD. Results. Forced expiratory volume in 1 second (FEV1) and forced vital capacity (FVC) were significantly decreased early after ESD (from 4.67 ± 0.84 L and 4.36 ± 0.85 L to 4.12 ± 0.78 L and 3.84 ± 0.82 L, respectively), although no patient complained of an aggravation of respiratory symptoms. Twelve patients (21%) had a positive response to methacholine provocation preoperatively, and all remained positive post surgery. The provocative concentration of methacholine, which brought about a 20% decrease in the FEV1 in the patients, was not significantly changed after surgery (from 5.1 ± 4.3 to 4.6 ± 4.6). Of 46 patients who had a negative result for methacholine challenge preoperatively, 12 (26%) became positive after surgery. In terms of the level of sympathectomy, T3 sympathectomy significantly increased the ratio of patients exhibiting a positive response to methacholine (from 19% to 34%, respectively) (p < 0.005). Conclusions. Thoracic sympathectomy can adversely affect lung function early after surgery, although the clinical significance is uncertain. It may also exert an influence on the development of bronchial hyperresponsiveness, especially when performed at the T3 level.

Bronchial hyper-responsiveness, subepithelial fibrosis, and transforming growth factor-β1 expression in patients with long-standing and recently diagnosed asthma

Introduction:Chronic inflammation in asthmatic airways leads to bronchial hyper-responsiveness (BHR) and the development of structural changes. Important features of remodeling include the formation of subepithelial fibrosis due to increased collagen deposition in the reticular basement membrane. Transforming growth factor (TGF)-β might be a central mediator of tissue fibrosis and remodeling.Materials and Methods:Immunohistochemistry was used to measure collagen III deposition and TGF-β1 expression in biopsies from patients with long-standing asthma treated with inhaled corticosteroids, patients with recently diagnosed asthma, and control subjects. Computer-assisted image analysis was used to evaluate total basement membrane (TBM) thickness.Results:Asthmatics, particularly those with long-standing asthma, had thicker TBMs than healthy subjects. Collagen III deposition was comparable in the studied groups. BHR was not correlated with features of mucosal inflammation and was lower in steroid-treated patients with long-standing asthma than in subjects with newly diagnosed asthma untreated with steroids. Epithelial TGF-β1 expression negatively correlated with collagen III deposition and TBM thickness.Conclusions:The study showed that TBM thickness, but not collagen III deposition, could be a differentiating marker of asthmatics of different disease duration and treatment. The lack of correlation between BHR and features of mucosal inflammation suggests the complexity of BHR development. Corticosteroids can reduce BHR in asthmatics, but it seems to be less effective in reducing subepithelial fibrosis. The role of epithelial TGF-β1 needs to be further investigated since the possibility that it plays a protective and anti-inflammatory role in asthmatic airways cannot be excluded.

Asthma, allergy, the athlete and the Olympics

As the 2008 Summer Olympics in Beijing approach, both the general public and health care professionals are gaining interest in the potential health implications of sport. When asthma and allergy are present in athletes, this may affect their performance and achievements and justify the special attention of health care professionals who specialize in taking care of top athletes. However, the impact of allergy and asthma on sport and exercise goes further than just top athletes. The Editors of Allergy decided that in this issue they would focus the attention of allergy and asthma specialists by presenting a series of articles on the relationship between sport, asthma and allergy in the hope that an increased awareness of these problems would be highlighted not only for sports medicine doctors but also for all practicing allergists. Exercise-induced asthma (EIA) is a general concern for growing children and adolescents. In most international guidelines, one of the main objectives of treating asthma during childhood is for the child to be able to master EIA. Also among athletes, and especially elite athletes, EIA and bronchial hyperresponsiveness (BHR) have become major problems with regard to the correct diagnosis and to treatment. EIA is increasingly common among the top athletes of several different types of sport. Traditionally this has been reported mainly in athletes competing in endurance sports in cold climates, especially among crosscountry skiers (1, 2) and swimmers (3, 4), but also among endurance athletes in summer sports (5). A surprisingly high prevalence of asthma (56%) diagnosed by the reversibility of lung function to inhaled s2-agonists (56%) was reported among professional Canadian football players (6). The prevalence of EIA among top athletes has increased over the past decades. Weiler et al. reported 11% prevalence of EIA among American athletes participating in the 1984 Summer Olympic Games (7) and an increase to a prevalence of more than 20% was noticed among American participants in the 1996 Summer Olympic Games in Atlanta (8).

Asthma Symptoms and Bronchial Reactivity in School Children Sensitized to Food Allergens in Infancy

Food allergy in infancy usually disappears but is followed primarily by respiratory allergy. We hypothesized that children allergic to common food allergens in infancy are at increased risk of wheezing illness and bronchial hyperresponsiveness during school age. In a case-control study 69 children 7.2 to 13.3 years of age allergic to egg (N = 60) and/or fish (N = 29) in early life (first 3 years) who attended our allergy outpatient clinic were recruited. They received follow-up for 1 year and were evaluated by parental questionnaire, skin prick testing, spirometry, and metacholine bronchial challenge. Another 154 children (70 sensitized to inhaled allergens) recruited selectively from a general population sample with no history of food allergy during their first 3 years served as control subjects. Twenty-three children (38.3%) maintained their sensitization to egg and 19 (65.5%) to fish; the prevalence of sensitization to ≥ 1 inhaled allergen(s) increased from 59.4% to 71% during childhood. Current asthma symptoms were reported more frequently in the study group than in either control groups, sensitized to inhaled allergens and non-sensitized. Children of the study group showed a significantly increased frequency of positive response to metacholine bronchial challenge compared to the control group as a whole; the difference was statistically indicative when study groups separately were compared to the sensitized control subjects. Multivariate logistic regression analysis showed that bronchial hyperresponsiveness, as well as reported current asthma symptoms were associated with early wheezing and early sensitization to inhaled allergens but not with atopic dermatitis in infancy or persistence of egg or fish allergy. Children allergic to egg or fish in infancy are at increased risk for wheezing illness and hyperactive airways in school age; asthma and bronchial hyperresponsiveness development is mostly determined by wheezing and senzitization to inhaled allergens in early life regardless of atopic dermatitis in infancy or retention of food allergy.