Airway Remodeling ; Asthma ; physiopathology ; Bronchial Hyperreactivity ; etiology ; Bronchitis ; physiopathology ; Humans

It is commonly accepted that airway hyperresponsiveness (AHR) is a chronic airway inflammation although the exact mechanism of its pathogenesis is still unclear. In the past ten years, an epithelial defect hypothesis has gradually gained supports from the main stream. Airway epithelium is no longer considered only as a simple mechanic barrier but an active interface between the inner and outer environment. Bronchial epithelial cells play a critical role in maintenance of homeostasis in the airway local microenvironment through a wide range of physiologic functions including anti-oxidation, exocrine/endocrine secretions, mucus production and antigen presentation under health and stressed/inflamed/injured conditions. It is reasonably hypothesized that disruption of these functional processes or defects in airway epithelium integrity may be the initial steps leading to airway hyperresponsiveness such as in asthma and chronic obstructive pulmonary disease.
Animals ; Bronchi ; cytology ; Bronchial Hyperreactivity ; physiopathology ; Epithelial Cells ; pathology ; Humans

OBJECTIVEAsthma is the most common chronic respiratory disease of children. The association between asthma and bronchial hyperresponsiveness (BHR) has been well-demonstrated. The objective of the study was to investigate relationship between the bronchial responsiveness and the peripheral obstruction in stable asthmatic children.

METHODSThirty-nine children with stable asthma, 28 boys and 11 girls with a mean age of 128 (77 - 197) months, received the bronchial provocation test by the maximal expiratory flow-volume (MEFV) curve measurement. The children were divided into two groups: one with maximal mid-expiratory flow (MMEF) < 80% (n = 15) and the other with MMEF >/= 80% (n = 24). Positive rates of bronchial provocation test were compared between groups of MMEF < 80% and >/= 80% and between the children whose relief duration was 12 months (n = 13). Statistical analysis was performed by using Chi-square, rank sum test or t test (SPSS10.0), P values < 0.05 were considered significant.

RESULTSIn the 39 stable asthmatic children, 15 (38%) were detected MMEF < 80% and 28 (72%) had BHR. There was no significant difference in BHR between the children with MMEF < 80% and those with MMEF >/= 80% (P > 0.05). There was no significant difference in BHR between the children whose relief duration was 12 months (P > 0.05), either.

CONCLUSIONSThe stable asthmatic children still had peripheral obstruction and BHR, which indicated the presence of airway inflammation. There was no significant difference in BHR between the children whose relief duration was 12 months.

Asthma ; physiopathology ; Bronchial Hyperreactivity ; physiopathology ; Bronchial Provocation Tests ; Child ; Female ; Humans ; Male ; Maximal Midexpiratory Flow Rate

Adult ; Bronchial Hyperreactivity ; physiopathology ; Bronchial Provocation Tests ; Chronic Disease ; Cough ; physiopathology ; Female ; Humans ; Male ; Middle Aged ; Respiratory Function Tests

Bronchial Hyperreactivity ; Case-Control Studies ; Child ; Child, Preschool ; Female ; Humans ; Male ; Rhinitis, Allergic, Perennial ; physiopathology ; Rhinitis, Allergic, Seasonal ; physiopathology

The aim of this study was to investigate the possible adverse effects of Asian dust events on respiratory health in asthmatic children. Fifty-two children with mild asthma were studied for eight consecutive weeks in the spring of 2004 (March 8 to May 2). During the study period, five Asian dust days were identified; we included a lag period of two days following each of the events. Subjects recorded their respiratory symptom diaries and peak expiratory flow (PEF) twice daily during the study period; and they underwent methacholine bronchial challenge tests. The subjects reported a significantly higher frequency of respiratory symptoms during the Asian dust days than during the control days. They showed significantly more reduced morning and evening PEF values, and more increased PEF variability (10.1%+/-3.5% vs. 5.5%+/-2.2%) during the Asian dust days than during the control days. Methacholine PC20 was not significantly different between before and after the study period (geometric mean: 2.82 mg/mL vs. 3.16 mg/mL). These results suggest that the short-term Asian dust events might be associated with increased acute respiratory symptoms and changes in PEF outcomes. However, there might be little long-term influence on airway hyperresponsiveness in children with mild asthma.
Adolescent ; Asthma/*physiopathology ; Bronchial Hyperreactivity/physiopathology ; Child ; *Dust ; Female ; Humans ; Male ; Methacholine Chloride/diagnostic use ; *Peak Expiratory Flow Rate ; Respiration Disorders/*etiology/physiopathology

BACKGROUND/AIMS: Many patients with aspirin-induced asthma have severe methacholine airway hyperresponsiveness (AHR), suggesting a relationship between aspirin and methacholine in airway response. This study was performed to determine whether methacholine AHR affects the response of asthmatics to inhaled aspirin. METHODS: The clinical records of 207 asthmatic patients who underwent inhalation challenges with both aspirin and methacholine were reviewed retrospectively. An oral aspirin challenge was performed in patients with a negative inhalation response. The bronchial reactivity index (BRindex) was calculated from the percent decrease in lung function divided by the last dose of the stimulus. RESULTS: Forty-one (20.9%) and 14 (7.1%) patients showed a positive response to aspirin following an inhalation and oral challenge, respectively. Only 24.3 and 14.3% of the responders had a history of aspirin intolerance, respectively. The methacholine BRindex was significantly higher in the inhalation responders (1.46 +/- 0.02) than in the oral responders (1.36 +/- 0.03, p < 0.01) and in non-responders (n = 141, 1.37 +/- 0.01, p < 0.001). The aspirin BRindex was significantly correlated with the methacholine BRindex (r = 0.270, p < 0.001). Three of four patients who received the oral challenge, despite a positive inhalation test, showed negative responses to the oral challenge. Two of these patients had severe AHR. CONCLUSIONS: A considerable number of asthmatic patients with no history of aspirin intolerance responded to the inhalation aspirin challenge. The airway response to aspirin was significantly correlated with methacholine-AHR, and a false-positive response to aspirin inhalation test seemed to occur primarily in patients with severe AHR.
Administration, Inhalation ; Adolescent ; Adult ; Aspirin/*administration & dosage/*adverse effects ; Asthma/*physiopathology ; Asthma, Aspirin-Induced/etiology/physiopathology ; Bronchial Hyperreactivity/physiopathology ; Bronchial Provocation Tests ; Drug Hypersensitivity/etiology/physiopathology ; Female ; Humans ; Male ; Methacholine Chloride/*administration & dosage ; Retrospective Studies ; Young Adult

OBJECTIVETo establish a method for measurement of airway resistance (sRaw) and reactivity in guinea pigs.

METHODSMethacholine spray at gradient concentrations was given to guinea pigs. PC100 was defined as the concentration of methacholine when the sRaw doubled in the guinea pigs using a double-chamber plethysmograph. The time for the recovery of PC100 resistance to baseline levels was measured. The sRaw and PC100 were measured twice on days 1 and 15 (4 time points) in the guinea pigs before and after OVA challenge.

RESULTSPC100 in a normal guinea pig airway was shown to recover the baseline level within 1 h. Double-chamber plethysmographical measurement of the sRaw and PC100 in normal guinea pigs did not show significant differences between the time points [sRaw: 3.25-/+0.67, 3.33-/+0.58, 3.30-/+0.56, and 3.32-/+0.75 cm H2O.s; log2PC100: 8.48-/+0.94, 8.64-/+1.04, 8.56-/+0.67, and 8.64-/+0.60, respectively, P>0.05]. The sRaw and airway reactivity were significantly increased in guinea pigs challenged with OVA [sRaw: 7.08-/+1.82 vs 2.87-/+0.53 cmH2O.s, P<0.01; log2PC100: 6.64-/+1.26 vs 8.48-/+1.17, P<0.01].

CONCLUSIONA double-chamber plethysmography for measurement of sRaw and airway reactivity in guinea pig is established successfully.

Airway Resistance ; Animals ; Asthma ; chemically induced ; physiopathology ; Bronchial Hyperreactivity ; etiology ; physiopathology ; Guinea Pigs ; Male ; Methacholine Chloride ; Plethysmography ; instrumentation ; methods ; Random Allocation

OBJECTIVE: Discussion of lung function changes in patients with allergic rhinitis and its clinical significance. METHOD: Using UNICAP100 allergen detector testing 64 patients of allergic rhinitis without asthma symptoms, testing the value of serum total IgE and using immunofluorescence methods for testing inhalation allergen, simultaneously checking the pulmonary function and bronchial provocation. Checking the lung function of 64 patients with non-symptoms of allergic rhinitis in other departments (control group), lung function were compared into two groups of patients. RESULT: In the allergic rhinitis group, 37 patients had abnormal lung function (57.81%), 8 cases in them had obstructive pulmonary ventilation, 12 cases had small airway dysfunction, 31 cases had increased airway resistance respectively. In the control group 15 patients (23.44%) had pulmonary function abnormalities, 2 cases had obstructive pulmonary ventilation, 4 cases had small airway dysfunction, 11 cases had increased airway resistance respectively. Changes in lung function compared in the two groups was statistically significant (P < 0.05). Allergic rhinitis patients with abnormal lung function bronchial provocation test positive rate was significantly higher than the normal lung function in patients with allergic rhinitis, there had statistically significant difference between the two groups (P < 0.05). CONCLUSION After checking the lung function of non-asthmatic symptom patients with allergic rhinitis, we could find abnormal lung function patients of allergic rhinitis and do bronchial provocation test in them, there has important clinical significance of early detection and treatment the patients of allergic rhinitis with bronchial asthma.
Adult ; Bronchial Hyperreactivity ; physiopathology ; Case-Control Studies ; Female ; Humans ; Male ; Nasal Septum ; abnormalities ; Peak Expiratory Flow Rate ; Respiratory Function Tests ; Rhinitis, Allergic, Perennial ; physiopathology

OBJECTIVE: To observe the relation between the expression of CTNNAL1 and the airway resistance in rats with airway hyperresponsiveness. METHODS: Thirty Wister rats were randomly divided into 5 groups: a normal control group, a 2 d ozone attack group, a 4 d ozone attack group, a 6 d ozone attack group, and a 6 d ozone attack+2 d dexamethasone treatment group (6 rats in each group). The distribution of CTNNAL1 was observed by in situ hybridization; the expression of CTNNAL1 was detected by fluorescence quantitative RT-PCR; the airway resistance was detected in by Buxco pulmonary function analysis system; and the relevance of the expression of CTNNAL1 and the resistance of respiratory tract in rat with airway hyperresponsiveness were analyzed. RESULTS: CTNNAL1 was distributed in bronchial epithelial cells, goblet cells, endothelial cells, and the alveolar wall. With the increase of the ozone attack, the expression of CTNNAL1 mRNA gradually reduced, the airway hyperresponsiveness was aggravated, and the airway resistance was increased. CONCLUSION During airway hyperresponse, the reduction of CTNNAL1 mRNA can increase the airway resistance. There is a negative correlation between the reduction of CTNNAL1 mRNA and the airway hyperresponsiveness. CTNNAL1 is an adhesion molecule related to airway hyperresponsiveness susceptibility.
Airway Resistance ; Animals ; Bronchial Hyperreactivity ; chemically induced ; metabolism ; physiopathology ; Female ; Inflammation ; chemically induced ; physiopathology ; Male ; Ozone ; RNA, Messenger ; genetics ; metabolism ; Rats ; Rats, Wistar ; alpha Catenin ; genetics ; metabolism