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121.
Formoterol administered by a dry-powder (DP) capsule inhaler was compared with a pressurized metered-dose inhaler (pMDI) with regard to bronchodilating and systemic effects. The study used a double-blind, crossover, double-dummy technique. Twelve patients with moderate reversible asthma in a stable phase were examined on two separate study days, and the inhalers were given in randomized order. After baseline measurements, increasing doses of formoterol were given at intervals of 75 min. FEV1 and heart rate and tremor measurements were repeated after each dose, and the doses were 12 + 12 + 24 + 48 μg, giving a total dose of 96 μg. The peak expiratory flow rate (PEFR) was recorded in the morning before the first dose, after the last dose, and then repeatedly at home until 19 h after the last dose. There was an equal increase in ventilatory capacity at each dose level, independent of inhaler device. Repeated PEFR measurements after the last dose did not reveal any differences in duration of effect. There was a slight but statistically significant increase in heart rate and tremor after the highest doses of the DP formulation compared to the pMDI. These systemic effects can probably be explained by the reduced oral deposition of the aerosol caused by using a spacer. This study indicates that the DP and pMDI formulations of formoterol are equipotent in bronchodilation. 相似文献
122.
Svendsen UG, Frølund L, Heinig JH, Madsen F, Nielsen NH, Weeke B. High-dose inhaled steroids in the management of asthma. A comparison of the effects of budesonide and beclomethasone dipropionate on pulmonary function, symptoms, bronchial responsiveness and the adrenal function.
The efficacy of budesonide (800 μg b.d.) and beclomethasone dipropionate (750 μg b.d.) in controlling the symptoms of asthma, pulmonary function, bronchial responsiveness to histamine, and adrenal function, was assessed in a double-blind, double-dummy cross-over study of 36 adult chronic asthmatic patients. The patients, the majority of whom were assessed to be affected to a severe degree, were insufficiently controlled in their current regimen of inhaled steroids and/or inhaled and oral bronchodilators. A 2 weeks baseline period preceded 6 weeks of treatment with each of the study drugs. Both treatment groups showed improvements from baseline in clinical assessment of lung function carried out after the first 6 weeks of treatment. No significant differences were seen throughout the entire 12 weeks study, when comparing the effects of the treatments on FEV1 FVC, PEF or the histamine PC20 . Asthma severity, symptom score and inhaled bronchodilator use showed the same results after both treatments. It is concluded that inhalations of budesonide and beclomethasone dipropionate in high doses are equally potent in the treatment of severe asthma. There is no significant influence on the adrenal function and no significant side effects during a period equal to that of the present study. 相似文献
The efficacy of budesonide (800 μg b.d.) and beclomethasone dipropionate (750 μg b.d.) in controlling the symptoms of asthma, pulmonary function, bronchial responsiveness to histamine, and adrenal function, was assessed in a double-blind, double-dummy cross-over study of 36 adult chronic asthmatic patients. The patients, the majority of whom were assessed to be affected to a severe degree, were insufficiently controlled in their current regimen of inhaled steroids and/or inhaled and oral bronchodilators. A 2 weeks baseline period preceded 6 weeks of treatment with each of the study drugs. Both treatment groups showed improvements from baseline in clinical assessment of lung function carried out after the first 6 weeks of treatment. No significant differences were seen throughout the entire 12 weeks study, when comparing the effects of the treatments on FEV
123.
Prenatal paracetamol exposure and risk of asthma and elevated immunoglobulin E in childhood 总被引:3,自引:0,他引:3
S. O. Shaheen R. B. Newson A. J. Henderson† J. E. Headley† F. D. Stratton† R. W. Jones† D. P. Strachan‡ the ALSPAC Study Team 《Clinical and experimental allergy》2005,35(1):18-25
BACKGROUND: We recently found that paracetamol (acetaminophen) use in late pregnancy was associated with an increased risk of early wheezing in the offspring. OBJECTIVE: To see whether use of paracetamol in late pregnancy is associated with an increased risk of asthma, wheezing and other atopic outcomes in the child at school age. METHODS: In the population-based Avon Longitudinal Study of Parents and Children, we measured associations of paracetamol and aspirin use in late pregnancy (20-32 weeks) with asthma, hayfever, eczema (n = 8511) and wheezing (8381) in the offspring at 69-81 months, and with atopy (positive skin prick test to Dermatophagoides pteronyssinus, cat or grass, n = 6527) and blood total IgE (n = 5148) at 7 years. We used logistic and linear regression to analyse binary outcomes and log-transformed IgE, respectively, controlling for potential confounders. RESULTS: Use of paracetamol, but not aspirin, in late pregnancy was positively associated with asthma (odds ratios (ORs), comparing children whose mothers took paracetamol 'sometimes' and 'most days/daily' with those whose mothers never took it, 1.22 (95% confidence interval (CI): 1.06-1.41) and 1.62 (95% CI: 0.86-3.04), respectively; P trend = 0.0037), wheezing (ORs 1.20 (95% CI: 1.02-1.40) and 1.86 (95% CI: 0.98-3.55), respectively; P trend = 0.011), and total IgE (geometric mean ratios 1.14 (95% CI: 1.03-1.26) and 1.52 (95% CI: 0.98-2.38), respectively; P trend = 0.0034), but not hayfever, eczema or skin test positivity. The proportion of asthma attributable to paracetamol use in late pregnancy, assuming a causal relation, was 7%. CONCLUSION: Paracetamol exposure in late gestation may cause asthma, wheezing and elevated IgE in children of school age. 相似文献
124.
Maintenance of asthma control by once-daily inhaled ciclesonide in adults with persistent asthma 总被引:3,自引:0,他引:3
Chapman KR Patel P D'Urzo AD Alexander M Mehra S Oedekoven C Engelstätter R Boulet LP 《Allergy》2005,60(3):330-337
BACKGROUND: Inhaled corticosteroids (ICS) are recommended therapy for persistent asthma, although side effects can limit appropriate use. Ciclesonide, a novel ICS, is activated in the lung, thereby reducing systemic activity and side effects. This 12-week, double-blind, randomized, parallel-group, placebo-controlled study evaluated the efficacy and safety of ciclesonide in adults with persistent asthma. METHODS: After a 2-week baseline period in which current ICS treatment was continued, 329 patients were randomized to receive ciclesonide 160 microg (n = 107) or 640 microg (n = 112) (ex-actuator doses, equivalent to 200 and 800 microg ex-valve, respectively), or placebo (n = 110) once daily in the morning. Efficacy was monitored by asthma symptom scores, rescue medication use, morning and evening peak expiratory flow (PEF) measurements, spirometry, and probability of study completion without experiencing lack of efficacy. RESULTS: Morning PEF remained stable with either ciclesonide dose but decreased with placebo; the differences were significant (P < 0.0001) for both ciclesonide doses vs placebo. The forced expiratory volume in 1 s and forced vital capacity decreased significantly with placebo (P < 0.005), but were unchanged with ciclesonide. Lack of efficacy was significantly greater for patients switched to placebo (63%) than it was for those treated with ciclesonide 160 microg (30%) (P < 0.0001 vs placebo) or ciclesonide 640 microg (31%) (P < 0.0001 vs placebo). There were no significant differences between the two tested doses of ciclesonide with respect to efficacy and safety. Serum and 24-h urine cortisol were unaffected by ciclesonide treatment. Both doses of ciclesonide were well tolerated with no cases of oral candidiasis. CONCLUSION: Ciclesonide (160 or 640 microg) once daily in the morning effectively maintains asthma control, does not affect cortisol levels, and has an adverse event profile comparable with placebo in adults with primarily mild to moderate asthma. 相似文献
125.
C. Blanco T. Carrillo J. Quiralte C. Pascual M. Martin Esteban R. Castillo 《Allergy》1995,50(3):277-280
We report a case of occupational bronchial asthma and rhinoconjunctivitis caused by Phoenix canariensis (PC) pollen. The canary palm is a type of palm tree, belonging to the Arecaceae family, which is widely distributed in frost-free regions as an ornamental tree. Our patient was referred because he suffered symptoms of bronchial asthma, rhinoconjunctivitis, and contact urticaria when pruning dried leaves from PC during the pollination months. The skin prick test (SPT) with a PC pollen extract was positive, as was the specific IgE to PC pollen determined by Phadezym RAST, indicating an IgE-mediated sensitization. The nonspecific bronchial provocation test (BPT) performed with methacholine disclosed a mild bronchial hyperreactivity, and specific BPT with PC pollen elicited an immediate fall of 25% in FEV1 with respect to baseline. On RAST inhibition studies, a significant cross-reactivity was found between PC pollen and date palm ( P. dactylifera ) pollen. These results suggest that PC pollen could be a potential allergen in PC-growing areas. 相似文献
126.
Y. Droma O. Kunii Y. Yangzom M. Shan L. Pingzo P. Song 《Clinical and experimental allergy》2007,37(9):1326-1333
BACKGROUND: The International Study of Asthma and Allergies in Childhood (ISAAC) demonstrated that large variations existed in the prevalence of symptoms of asthma, allergic rhinoconjunctivitis and eczema throughout the world and that environmental factors and lifestyle customs are major determinants of the prevalence and severity of these diseases. However, the relevant data about children living at high-altitude locations were considered to be underreported. OBJECTIVE: The ISAAC Phase III programme was carried out in Lhasa, the Tibetan Autonomous Region in China, at an elevation of 3658 m above sea level to examine the occurrence of asthma, allergic rhinoconjunctivitis and eczema in schoolchildren aged 13-14 years. METHODS: All 3196 schoolchildren in eight public junior high schools in urban Lhasa who were confirmed to be 13-14 years old were invited and participated in both written and video questionnaire investigations, among which 3190 pieces of data (49.8% of boys and 50.2% of girls) were validated and analysed. RESULTS: Among the overall observations, the prevalence of 'having ever experienced wheezing', 'current wheezing' and 'diagnosed to have asthma' was 1.4%, 0.8% and 1.1%, respectively. The prevalence of current exercise-induced asthma and current nocturnal cough was 7.1% and 4.6%, respectively. The current prevalence of allergic rhinoconjunctivitis and eczema was 5.2% and 0.4%, respectively. In addition, the prevalence of rhinoconjunctivitis symptoms during the past 12 months showed no discernable differences throughout the year. CONCLUSION: The prevalence of asthma, allergic rhinoconjunctivitis and eczema over the past 12 months was the lowest among the centres, that performed ISAAC worldwide. 相似文献
127.
OBJECTIVE: To examine the feasibility of using a behavioral coding system, the Five Minute Speech Sample (FMSS), to estimate the prevalence of relationship difficulties between parents and physicians in a pediatric asthma care setting. METHOD: The FMSS was administered to 20 parents of children with severe, chronic asthma and to the physicians they worked with during a brief day program admission. RESULTS: Rates of relationship difficulties between parents and physicians ranged from 15% to 40%, comparable to those previously identified in patient-therapist relationships in psychiatric populations. CONCLUSIONS: Although further information is needed about validity and reliability, the FMSS appears to provide clinically relevant information about the parent-physician relationship in the context of pediatric chronic illness. 相似文献
128.
Contribution of histamine and prostanoids to bronchoconstriction provoked by inhaled bradykinin in atopic asthma 总被引:6,自引:1,他引:6
Bradykinin, a nonapeptide cleavage product of high molecular weight kininogen, is a potent bronchoconstrictor agonist in asthma; however, its mechanism of action is not known. Since bradykinin has been shown to stimulate mediator release from mast cells and augment the release of prostanoids, we have examined the effect of a selective histamine H1 receptor antagonist, terfenadine and a potent cyclooxygenase inhibitor, flurbiprofen on bronchoconstriction provoked by inhaled bradykinin in asthma. As a bronchial provocation procedure bradykinin challenge was repeatable to within 1 doubling dilution. In nine atopic asthmatic subjects, terfenadine 180 mg, when compared to placebo, increased the geometric mean provocation concentration of inhaled agonist required to reduce FEV1 by 20% of baseline (PC20) from 0.7 to greater than 22.9 mg/ml for histamine (P less than 0.01) and 0.3 to 0.5 mg/ml for bradykinin (P less than 0.01). In a further nine atopic asthmatics, flurbiprofen 150 mg when compared to placebo produced a small but significant protection of the airways against bradykinin, geometric mean PC20 increasing from 0.40 to 0.79 mg/ml (P less than 0.05). We conclude that bradykinin is a potent bronchoconstrictor agonist in asthma, being approximately 9.5 times more potent than histamine in molar terms. Pharmacological intervention with terfenadine and flurbiprofen led to a significant protection of the airways against the constrictor effect of bradykinin but the effect in each case was small. Thus, while histamine and prostanoids may contribute as mediators of bradykinin-induced bronchoconstriction, they are unlikely to account for the majority of the response. 相似文献
129.
ST2作为Th2细胞亚群标志以及其与支气管哮喘的关系的研究 总被引:2,自引:0,他引:2
各自主要分泌IFN γ和IL 4的Th1和Th2亚群 ,与临床疾病的关系十分密切。如何从表面标志上加以区分是一项迫切需要解决的问题。ST2是近年来提出的Th2细胞的稳定标志物。本工作在体外成功地诱导人脐带血T细胞向Th1或Th2分化的基础上 ,应用逆转录PCR分析了ST2mRNA的表达特点。证实ST2在人Th2细胞上的选择性表达。为了探索ST2、Th2与支气管哮喘的关系 ,本工作进一步检测了正常人和支气管哮喘患者外周血单个核细胞中 β actin、ST2以及IFN γ和IL 4的mRNA水平。结果显示 :支气管哮喘患者ST2mRNA水平升高 ,IL 4水平也明显升高 ,但IFN γ无变化。这提示ST2作为Th2细胞的标志物 ,有可能成为Th2极化性疾病如哮喘发病机制研究的一个参考性标志 ,至于ST2是否有可能作为治疗的靶分子 ,有待进一步探讨 相似文献
130.
D J Wheeler A Robins D I Pritchard R V Bundick F Shakib 《Clinical and experimental immunology》1995,102(1):85-90
In this study, we investigated the modulatory effects of CsA on in vitro synthesis of IgE, IgG1 and IgG4 by human peripheral blood mononuclear cells (PBMC). In contrast to its known immunosuppressive effect, we have demonstrated that a low dose of CsA (10(-7) M, 120 ng/ml) potentiated IgE production by up to 40-fold (i.e. from 33 +/- 4.5 to 1346 +/- 290 ng/ml). This potentiation was specific for IgE since no such effect was demonstrable with IgG1 and IgG4. Potentiation of IgE synthesis by CsA in the PBMC cultures was partly due to CsA acting on T cells, as demonstrated by the addition of CsA-treated T cells to T cell-depleted cultures. However, potentiation was also demonstrable in a T cell-depleted, anti-CD40-stimulated culture (four-fold increase from 400 +/- 48 to 1606 +/- 127 ng/ml). Our data therefore suggest that there are at least two mechanisms for CsA-induced potentiation of IgE synthesis, one T cell-dependent and the other T cell-independent. The clinical implications of these findings are discussed with regard to the use of CsA in the treatment of Th2-mediated diseases. 相似文献