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21.
BACKGROUND: Carbon monoxide (CO) has emerged as an endogenously produced gaseous mediator known to be involved in bronchial smooth muscle regulation. Increased amounts of CO have been found in exhaled air during asthma and lower airway inflammation. Recently CO has been shown to be produced in the nasal airways, but there are no reports of altered CO levels in nasal airways during inflammation. OBJECTIVE: This study was designed to investigate if CO levels increase in the human nasal airways during inflammatory conditions, such as allergy and upper airway respiratory tract infection (URTI). METHODS: CO was sampled separately from the upper and lower airways of 13 healthy control subjects, six patients with a history of allergic rhinitis and six patients with URTI. RESULTS: Nasal CO levels were increased in subjects with allergic rhinitis, compared to healthy controls (2.07 +/- 0.15 ppm, n = 6 and 1.62 +/- 0.08 ppm, n = 13, respectively, P < 0.01). CO levels were also increased in patients with URTI, compared to the same controls (1.92 +/- 0.09 ppm, n = 6, P < 0.05). Normal levels of CO were found in air from the lower airways among subjects with allergic rhinitis, whereas corresponding levels in the URTI patients were increased. CONCLUSION: The present data demonstrates that upper airway CO levels increase in parallel with different inflammatory stimuli, such as allergy and infection, suggesting a role for CO as marker or mediator of nasal inflammation. 相似文献
22.
A. S. Carney D. G. Powe† R. S. Huskisson† N. S. Jones 《Clinical and experimental allergy》2002,32(10):1436-1440
BACKGROUND: The pathophysiology of idiopathic rhinitis is unknown although evidence is accumulating to suggest that many patients may have a localized form of allergic rhinitis in the absence of other atopic symptoms and markers. This study compares detailed nasal challenge results obtained from patients with idiopathic rhinitis to those of atopic and normal controls. METHODS: Patients with idiopathic rhinitis (n = 23), perennial allergic rhinitis (n = 8) and normal controls (n = 8) underwent a normal saline challenge to exclude hyper-reactivity and then bilateral nasal allergen challenges. Nasal patency was assessed by anterior active rhinomanometry. RESULTS: All of the patients with atopic rhinitis demonstrated positive bilateral allergen challenges. All normal control subjects had bilateral negative challenges. Two patients in the idiopathic group tested positively to saline and were excluded from further study with 62% of the remainder testing positive to allergens. Of the idiopathic patients testing positive, 85% were sensitive to house dust mite. CONCLUSION: A significant proportion of patients with idiopathic rhinitis have positive nasal challenges, the vast majority to house dust mite allergen. These findings add to the weight of evidence that suggests 'localized allergy' may exist in the absence of systemic atopic markers. 相似文献
23.
Lower airway inflammatory responses to repeated very-low-dose allergen challenge in allergic rhinitis and asthma 总被引:2,自引:0,他引:2
BACKGROUND: Low-dose allergen challenge (LDAC) may be a useful tool for studying the capacity of allergens to induce airway inflammation in atopic subjects. OBJECTIVE: To evaluate lower airway inflammatory changes following repeated inhalation of very low doses of allergen (VLDAC) in non-asthmatic subjects with allergic rhinitis (NAAR) compared with mild allergic asthmatic subjects (AA). METHODS: Fourteen NAAR and 11 AA were seen out of the pollen season and had skin prick tests with common aeroallergens. Baseline spirometry (S) and methacholine challenge (MC) were done and blood and induced sputum (IS) differential cell counts were obtained. Each subject underwent VLDAC on four consecutive mornings with a relevant allergen. S, MC, and blood and IS samplings were repeated 6 h after the second and fourth VLDAC and one week later. RESULTS: Although there were, as expected, no changes in FEV1 or PC20 in either group, mean percentage eosinophils on IS were significantly increased in NAAR on day 2 of VLDAC and decreased in all but one subject on day 4, with a tendency to return to baseline levels one week later. In AA, there was a non-significant trend for sputum eosinophils to increase on day 2; four subjects showed a decrease of eosinophils on day 4 of VLDAC. There was a correlation between eosinophil cationic protein (ECP) levels and eosinophil counts in NAAR throughout the study. There were no variations in other sputum cells or blood inflammatory cells. CONCLUSION: VLDAC can increase the percentage of eosinophils in IS of NAAR subjects without associated respiratory symptoms nor physiological modifications. A reduction in eosinophilic response despite repeated exposure, more common in NAAR subjects, suggests an adaptation process that needs to be further evaluated. 相似文献
24.
25.
Shuei-Tu Chen Ko-Hsiu Lu Hai-Lun Sun Wen-Tung Chang Ko-Huang Lue Ming-Chih Chou 《Pediatric allergy and immunology》2006,17(1):49-54
Leukotriene receptor antagonists (LTRAs) were recently added to the method of treating allergic rhinitis (AR). However, in children under 6 yr old, there has been no study about its efficacy in treating AR. We aim to compare the clinical efficacy of montelukast, cetirizine and placebo in the treatment of children from 2 to 6 yr old with perennial allergic rhinitis (PAR), to see if there are any significant differences. Sixty children were selected and treated with montelukast, or cetirizine, or placebo once daily. The efficacy of the three agents was compared with the Pediatric Rhinoconjunctivitis Quality of Life Questionnaire (PRQLQ) and Total Symptom Score (TSS) by diary. In addition, we also examined serum IgE, serum eosinophil cationic protein (ECP), blood eosinophil counts, nasal airway resistance (NAR) and eosinophil percentage in nasal smears. The results revealed that both montelukast and cetirizine were significantly efficacious compared with placebo in NAR, eosinophil percentage in nasal smears, PRQLQ, TSS and all symptom items except nasal itching, throat itching and tearing. For nasal itching, only cetirizine was significantly efficacious. On the other hand, for night sleep quality, montelukast was significantly superior to cetirizine. 相似文献
26.
鼻内镜下等离子低温射频治疗常年性变应性鼻炎的临床观察 总被引:2,自引:1,他引:1
目的探讨鼻内镜下等离子低温射频治疗常年性变应性鼻炎(PAR)的疗效及其优越性。方法在鼻内镜下用等离子低温射频治疗PAR48例,按照海口会议修订的“过敏性鼻炎诊断和疗效评定标准”,用计分法分别评定其疗效。结果该组48例术后随访半年进行评价,其中显效27.1%(13/48),有效58.3%(28/48),无效14.6%(7/48),总有效率为85.4%。疗效评分显示治疗前平均总分为(9.58±1.69)分,治疗后为(5.63±1.15)分(P<0.05)。结论鼻内镜下等离子低温射频烧灼筛前神经终末区域治疗PAR,具有简便、安全等优点,短期效果显著,特别适用于临床上应用抗组胺类药物及鼻内应用糖皮质激素治疗效果不甚理想及由于各种原因不能长期接受抗组胺类药物及鼻内应用糖皮质激素治疗的患者;但长期疗效有待进一步研究。 相似文献
27.
施地瑞玛生理性海水鼻腔喷雾器治疗小儿干燥性鼻炎的临床观察 总被引:1,自引:0,他引:1
目的:探讨施地瑞玛生理性海水鼻腔喷雾器治疗小儿干燥性鼻炎的疗效。方法:将58例患儿随机分成2组,2组均不使用其他药物。治疗组给予施地瑞玛生理性海水鼻腔喷雾器喷鼻;对照组给予生理性盐水滴鼻液滴鼻,观察2组治疗前后症状、体征及有效率。结果:根据2组的主要症状、体征及疗效,治疗组优于对照组(P<0.05)。结论:生理性海水鼻腔喷雾器治疗小儿干燥性鼻炎,可以缩短病程,改善鼻腔功能,疗效确切,且使用安全、舒适、方便,可以作为治疗小儿干燥性鼻炎的理想药物。 相似文献
28.
The effectiveness of intranasal corticosteroids in combined allergic rhinitis and asthma syndrome 总被引:2,自引:0,他引:2
Background Allergic rhinitis (AR) and asthma often coexist and may represent two manifestations of the same disease recently named combined AR and asthma syndrome (CARAS). Aim To review the common pathophysiology of combined AR and asthma and to investigate the efficacy of intranasal corticosteroids (INCS). Methods Medline was used to identify articles relevant to mechanisms. A Cochrane systematic review was performed to assess the efficacy of INCS in CARAS. Results There is cross‐talk, evidence of a common inflammatory response in both sites, linked by a systemic component. The efficacy of anti‐inflammatory INCS on asthma outcomes was assessed in a systematic review of 12 randomized controlled trials involving 425 subjects. After INCS there were non‐significant trends for improvement in asthma symptom score (standardized mean difference (SMD) of 0.61; P=0.07), forced expiratory volume in 1 s (SMD of 0.31; P=0.08), and morning peak expiratory flow (weighted mean difference of 36.51; P=0.06). There was no impact on methacholine airways responsiveness (SMD of ?0.20; P=0.4). The review identified two promising new treatment options in united airway disease such as INCS as monotherapy in rhinitis and mild asthma, and a combined intranasal and intrabronchial corticosteroid (IBCS) deposition technique. Conclusion Common mucosal inflammatory responses occur in CARAS. This systematic review shows trends for a benefit of INCS in CARAS, but recognizes that more research is needed. At this stage, the current best practice is to treat asthma conventionally with IBCS with or without β2‐agonist and to add INCS to improve specific rhinitis symptoms. 相似文献
29.
30.
L. Cheng †‡ T. Enomoto§ T. Hirota† M. Shimizu † N. Takahashi† M. Akahoshi† A. Matsuda† Y. Dake§ S. Doi¶ K. Enomoto A. Yamasaki S. Fukuda X.-Q. Mao J. M. Hopkin M. Tamari† T. Shirakawa † 《Clinical and experimental allergy》2004,34(8):1192-1201
BACKGROUND: A recent report provided evidence that a disintegrin and metalloprotease domain 33 (ADAM33), a member of the ADAM family, is a novel susceptibility gene in asthma linked to bronchial hyper-responsiveness. However, there has been no investigation of the genetic role of ADAM33 variants in nasal allergy. OBJECTIVE: The purpose of this study was to test the association between ADAM33 polymorphisms and Japanese cedar pollinosis (JCPsis), a most common seasonal allergic rhinitis in Japan. METHODS: We conducted a case-control association study among a Japanese population, involving 95 adult individuals with JCPsis and 95 normal healthy controls. A total of 22 single-nucleotide polymorphisms (SNPs) in ADAM33 were genotyped using PCR-based molecular methods. RESULTS: Six SNPs of ADAM33 gene, three in introns (7575G/A, 9073G/A and 12540C/T) and three in the coding region (10918G/C, 12433T/C and 12462C/T), were strongly associated with JCPsis (P = 0.0002-0.022 for absolute allele frequencies) and most of the SNPs were in linkage disequilibrium with each other. A higher frequency of the common alleles of these SNPs was noted for the subjects with JCPsis in comparison with healthy controls. We also identified a haplotype associated with the disease susceptibility. In addition, associations were found between ADAM33 polymorphisms and various cedar pollinosis phenotypes including clinical severity, eosinophil counts in nasal secretion and allergen-specific IgE levels in sera, but not total serum IgE levels. CONCLUSION: These results indicate that polymorphisms in the ADAM33 gene are associated with susceptibility to allergic rhinitis due to Japanese cedar pollen, but the functional relationship still needs clarification. 相似文献