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This study is an extended follow-up for 24 months of a 12-week trial to study the long-term clinical efficacy of low-dose inhaled budesonide (BUD) once or twice daily in children with mild asthma. A total of 122 children (mean age 9.7 years, girls/boys; 42/80) with mild asthma (FEV1 103.7% of predicted, reversibility in FEV1 3.5%, and fall in FEV1 after exercise 12.2%), not previously treated with inhaled steroids, were included in a double-blind, randomized, parallel-group study. The children were treated with inhaled BUD 100 or 200 microg administered via Turbuhaler once daily in the morning, 100 microg twice daily, or placebo for 27 months. Exercise and methacholine challenges were performed at 3-month intervals the first year and at 6-month intervals the second year, in a total of seven visits. A significant dose-response effect favoring BUD 200 microg daily (vs 100 microg daily) was found when comparing changes in FEV1, FEF25%, and FEV50%; the fall in FEV1 after an exercise test; and the effect on blood eosinophils. Bronchial hyperreactivity to methacholine decreased significantly on three visits in patients treated with BUD 200 microg daily compared to placebo. Growth rate was not significantly affected except in children aged 7-11 years at baseline after 12 months of treatment. In conclusion, 100 or 200 microg daily of inhaled BUD for 27 months is safe and effective in protecting against exercise-induced asthma and achieving nearly normal lung function. Baseline lung function was not significantly affected in this group of children with mild asthma. 相似文献
146.
Kawano T Matsuse H Kondo Y Machida I Saeki S Tomari S Mitsuta K Fukushima C Obase Y Shimoda T Kohno S 《The Journal of allergy and clinical immunology》2004,114(6):398-1281
BACKGROUND: The exact mechanism of aspirin-induced asthma is not clear. It has been postulated that precipitation of asthma attacks by aspirin is linked to inhibition of COX activity and massive release of cysteinyl leukotriene into the airway. Tacrolimus, a macrolide-derived immunosuppressant, is used for immunosuppression in organ transplantation and also for allergic diseases such as atopic dermatitis. OBJECTIVE: We evaluated the effects of tacrolimus in aspirin-induced asthma by using a double-blind, crossover study design. METHODS: Twelve patients with aspirin-induced asthma (male:female, 3:9; mean age +/- SD, 36.7 +/- 7.2 years) received either tacrolimus (0.1 mg/kg) or placebo 2 hours before the threshold dose of oral aspirin. RESULTS: In the placebo arm, oral aspirin significantly decreased FEV 1 concomitant with significant increases in sputum eosinophilic cationic protein and urinary leukotriene E(4) levels. Tacrolimus significantly inhibited bronchoconstriction and abrogated aspirin-induced increase in both sputum eosinophilic cationic protein and urinary leukotriene E(4) levels. CONCLUSION: The current study suggested that tacrolimus inhibited bronchoconstriction to a threshold dose of aspirin by inhibition of cysteinyl leukotriene excretion. 相似文献
147.
Prevalence of asthma, allergic rhinoconjunctivitis and allergic sensitization in Mongolia 总被引:5,自引:0,他引:5
Viinanen A Munhbayarlah S Zevgee T Narantsetseg L Naidansuren Ts Koskenvuo M Helenius H Terho EO 《Allergy》2005,60(11):1370-1377
BACKGROUND: Studies in countries, such as Mongolia, which are in transition from farming to industrial society permit evaluation of the impact of environmental change on atopic diseases. METHODS: In the screening study, questionnaire data were obtained from 9453 subjects aged 10-60 years. In the clinical study, a subsample of 869 subjects (participation rate 50.0%) was examined. A questionnaire-based interview, clinical examination, skin prick tests, spirometry and bronchodilation test or methacholine challenge test were used to define the clinical diagnoses. The prevalences of atopic diseases were evaluated at the population level using two-phase data and sampling weights. RESULTS: The prevalences of asthma, allergic rhinoconjunctivitis and allergic sensitization with 95% confidence intervals were 1.1% (0.3-2.0%), 9.3% (4.0-14.6%) and 13.6% (7.4-19.9%) in Mongolian villages, 2.4% (1.4-3.5%), 12.9% (8.2-17.7%) and 25.3% (17.1-33.6%) in rural towns and 2.1% (1.3-3.0%), 18.4% (13.3-23.4%) and 31.0% (24.5-37.5%) in Ulaanbaatar city, respectively. The prevalence of allergic rhinoconjunctivitis (P = 0.02) and allergic sensitization (P = 0.003) increased significantly with increasing urbanization. CONCLUSIONS: The prevalences of atopic diseases were low in rural Mongolia and increased with increasing urbanization suggesting that rural living environment protects against atopy. 相似文献
148.
Infantile hemangioma is a proliferation of beta 4-negative endothelial cells adjacent to HLA-DR-positive cells with dendritic cell morphology 总被引:4,自引:0,他引:4
Although hemangioma is referred as to the most common tumor in infancy, the underlying pathogenetic events and the biologic origin of this benign vascular neoplasm have remained obscure. By using immunohistochemistry on frozen sections of infantile hemangiomas, we show here that proliferating endothelial cells abundantly expressed alpha(v)beta(3) but lacked beta(4) integrins. Instead, regressing and involuting infantile hemangiomas due to treatment with IFN-alpha showed positive staining of beta(4) integrin, which might point to the angiogenic significance of beta(4) integrin in infantile hemangiomas. Moreover, immunofluorescence analysis revealed the existence of HLA-DR(+), mostly CD68(+) and partly DC-SIGN/CD209(+) cells with dendritic cell morphology in the intimate vicinity of hemangiomatous vessels. Such cells were also detected in the dermal microvascular unit in normal skin. The coupled occurrence of vascular structures and perivascular cells that were stained positive with markers of monocyte or macrophage or dendritic cells might suggest that the development of infantile hemangioma is a result of vasculogenesis, that is, the formation of primitive blood vessels from angioblasts, rather than of angiogenesis, that is, the sprouting of capillaries from preexisting vessels. 相似文献
149.
150.
Systemic Administration of Immunostimulatory DNA Sequences Mediates Reversible Inhibition of Th2 Responses in a Mouse Model of Asthma 总被引:10,自引:0,他引:10
Broide DH Stachnick G Castaneda D Nayar J Miller M Cho JY Roman M Zubeldia J Hayashi T Raz E Hyashi T 《Journal of clinical immunology》2001,21(3):175-182
This study investigated whether immunostimulatory DNA sequences (ISS) induce a transient or sustained inhibition of Th2 responses to inhaled antigen. We sensitized mice with subcutaneous injections to develop a Th2 response to ovalbumin (ova) and then administered a dose of ISS prior to ova inhalation challenge. Mice were then rechallenged with ova by inhalation a second time at varying time points after the first ova inhalation (1 to 8 weeks later) to determine whether the ISS dose administered prior to the first ova inhalation protected against a subsequent second ova inhalation challenge. A single dose of ISS inhibited the Th2 response to the first inhalation of ova antigen, as well as 4 weeks later to the second inhalation of ova. However, ISS did not inhibit a Th2 response to the second inhalation of ova 8 weeks later. The reversible inhibition of Th2 responses at 8 weeks suggests the need for repeated ISS administration at monthly intervals. 相似文献