哮喘儿童呼出气一氧化氮水平的测定

目的：　探讨哮喘儿童呼出气一氧化氮(exhalednitricoxide,eNO)水平及其意义。方法：　设定13～15cmH2O呼出气阻力以关闭软腭,用化学发光法测定34例6～14岁哮喘儿童和36名6～13岁非呼吸道疾病儿童单次呼吸的eNO浓度 ,同时测定一秒钟用力呼气容积占预计值百分比 (FEV1%)。结果：哮喘儿童的eNO浓度为 (89.4± 56 .4) ppb ,较非呼吸道疾病儿童eNO浓度 [(15 .8±5.8) ppb]显著增高 (P<0.01) ;哮喘儿童eNO浓度与FEV1%之间无显著相关性(r=0.06 ,P>0.05)。结论：　哮喘儿童eNO浓度高于正常,其变化与FEV1%无关。     

Exhaled nitric oxide measurements in childhood asthma: comparison of two sampling techniques

Nitric oxide (NO) is being increasingly used to assess airway inflammation in childhood. The method recommended by the American Thoracic Society workshop is for a prolonged expiration against a resistance. However, this is very difficult to apply in young children. As a result there have been a number of studies in which mixed expired gas has been collected and analyzed for NO content as this requires very little cooperation. This method has, however, yet to be fully validated. The aims of this study were to compare the two sampling techniques of exhaled NO concentrations in asthmatic and healthy children and to assess the correlation between NO levels and spirometry values in asthmatic children We studied 25 control children, mean age 11.5 y, and 20 asthmatics, mean age 12 y. The exhaled NO was sampled using both the single breath technique (SB) and by measuring the NO content in mixed expired air after 1 min tidal breathing (ME). Forced expiratory volume in 1 s (FEV(1)) and expiratory flow rates at 25%, 50%, and 75% of vital capacity (FEF(25), FEF(50), FEF(75), respectively) were measured by compact II spirometer (best of three) in the 20 asthmatic children. The NO level was significantly higher in the asthmatics versus the control children when measured by SB (p = 0.0015) but not when measured by ME (p = 0.1913). The NO results measured by SB were significantly higher than ME results in the asthmatic children (p = 0.008). The NO levels were negatively correlated to FEV(1), FEF(25), FEF(50), and FEV(75) when measured by SB (p < 0.02) but not when measured by ME. The SB but not the ME method for measuring expired NO discriminates between asthmatic and control children and correlates well with the degree of airway obstruction. The use of the ME technique remains unproven.     

哮喘患儿血浆一氧化氮、环磷酸腺苷/环磷酸鸟苷比值变化的临床意义

目的　研究支气管哮喘患儿血浆一氧化氮 (NO)、环磷酸腺苷 (cAMP) /环磷酸鸟苷 (cGMP)比值变化及其临床意义。方法　采用硝酸还原酶法和放射免疫法测定哮喘患儿 4 0例急性期和缓解期血浆NO3 -/NO2 -、cAMP及cGMP水平与cAMP/cGMP比值变化 ,并设 2 3例健康儿童为对照组。结果　 1.哮喘患儿急性期血浆NO3 -/NO2 -水平显著高于缓解期和对照组 (P均 <0 .0 1)。 2 .哮喘患儿急性期血浆cGMP水平明显高于缓解期 (P <0 .0 5 ) ,显著高于对照组 (P <0 .0 1)。 3.哮喘患儿急性期血浆cAMP明显低于缓解期和对照组 (P均<0 .0 1)。 4 .哮喘患儿急性期cAMP/cGMP比值显著低于缓解期和对照组 (P均 <0 .0 1)。 5 .缓解期血浆NO3 -/NO2 -和cGMP水平下降 ,cAMP水平上升及其cAMP/cGMP比值与对照组相比 ,差异无显著性 (P均 >0 .0 5 )。6 .哮喘患儿急性期血浆NO3 -/NO2 -与cGMP水平呈正相关 (r =0 .4 0 1　P <0 .0 1)。结论　血浆内源性NO、cAMP、cGMP可能参与哮喘的发病机制 ,血浆NO、cAMP/cGMP比值变化可作为监测和指导哮喘患儿疗效和评价哮喘药物疗效的较好生化指标。     

Nitric oxide metabolites in induced sputum: a noninvasive marker of airway inflammation in asthma

OBJECTIVE: This study was designed to examine for nitric oxide (NO) metabolites in induced sputum as a marker of airway inflammation in asthmatic children. DESIGN. Prospective interventional SETTING: Pediatric Allergy and Asthma Clinic of a tertiary care referral hospital in Northern India. SUBJECTS: Twenty-one children with asthma who were not receiving corticosteroids for the preceding 3 months and 10 healthy controls were enrolled. METHODS: Hypertonic saline-induced sputum was obtained at study entry in controls, and at study entry and after 6 weeks of inhaled corticosteroid (ICS) therapy in asthmatic children. Fresh expectorated sputum was treated with dithiothreitol and cytospinned for cell count. NO metabolites were measured in the supernatant by the modified Griess reaction. RESULTS: Asthmatic children, compared with controls, had significantly higher concentration of NO metabolites (22.4 +/- 209.69 vs 39.2 +/- 15.9 (moL/L, P <0.01) and a higher percentage of eosinophils (15.3 +/- 12.0 vs 0.8 +/- 1.1%, P <0.01) in induced sputum. Both NO metabolites and eosinophil percentage declined following treatment with ICS for 6 weeks (P <0.01). CONCLUSION: The study confirms that the level of NO metabolites is increased in the tracheobronchial secretions of asthmatic children and decreases following ICS therapy. Measurement of NO metabolites in induced sputum may be useful for monitoring airway inflammation in children with asthma.     

Exhaled carbon monoxide in childhood asthma.

OBJECTIVES: Oxidative stress and inflammation induce the expression of heme oxygenase-1, which produces carbon monoxide (CO), and nitric oxide synthase, which produces nitric oxide (NO). Exhaled CO and NO levels are elevated in asthmatic patients and are decreased after corticosteroid treatment, suggesting that they may be useful as noninvasive markers of airway inflammation. STUDY DESIGN: We measured forced expiratory volume in the first second, PC(20), and exhaled CO and NO levels in 29 children (18 boys, mean age 11.5 +/- 0.53 years) with asthma of different severity and 40 nonsmoking children without asthma (21 boys, mean age 8.1 +/- 0.35 years). We also studied whether upper respiratory tract infections were associated with elevated exhaled CO. RESULTS: Exhaled CO levels (ppm) were significantly higher (2.17 +/- 0.21) in children with persistent asthma compared with those in children with infrequent episodic asthma (1.39 +/- 0.18, P <.05) and healthy children (1.01 +/- 0.12, P <.001). The CO levels in children with infrequent episodic asthma and the normal control group, however, were not different. In contrast, exhaled NO levels (ppb) were higher in children with persistent asthma (24.2 +/- 5.9, P <.001) and infrequent episodic asthma (14.5 +/- 3.73, P <.05) than in normal subjects (5.1 +/- 0.24), but no significant difference was seen between the 2 asthmatic groups. In healthy children with upper respiratory tract infections (n = 12), exhaled CO concentrations were significantly elevated (2.16 +/- 0.33) during the acute symptomatic phase. No correlation was found between exhaled CO and forced expiratory volume in the first second or PC(20). CONCLUSIONS: Noninvasive measurement of exhaled CO may provide complementary data for assessment of asthma control in children. However, elevated CO levels are nonspecific and may be found in association with an acute viral illness.     

哮喘患儿血清白细胞介素-16、-10和免疫球蛋白E测定的意义

目的探讨哮喘患儿血清IL-16、IL-10和IgE水平测定的意义。方法对18例哮喘患儿及对照组14例健康儿童进行IL-16、IL-10和IgE水平测定并作相关性分析。结果哮喘患儿IL-16、血总IgE水平明显高于对照组P<0.05,P<0.01,而IL-10水平则低于对照组(P<0.05)。哮喘患儿血清IL-16水平与总IgE呈正相关(r=0.715P<0.01);IL-10水平与IgE呈负相关(r=-0.885P<0.01)。结论哮喘患儿气道炎症与IL-16的升高、IL-10降低有关,提示可针对IL-16、IL-10在气道炎症中作用的不同特点采取治疗十分必要。     

哮喘患儿诱导痰液中NO_3~-/NO_2~-含量的变化及其意义

探讨儿童哮喘诱导痰液中一氧化氮(NO)代谢终产物硝酸盐/亚硝酸盐(NO_3~-/NO_2~-)含量的变化及临床意义,采用3％高渗盐水雾化吸入诱导患儿咳痰,0.1％DTT和PBS缓冲液裂解痰液,应用硝酸酶还原法和荧光酶标法分别测定诱导痰液中No_3~-/NO_2~-和嗜酸性粒细胞阳离子蛋白(ECP)含量,便携式肺功能仪测定肺通气功能。结果表明,稳定期、轻度和中、重度发作期患儿诱导痰液中NO_3~-/NO_2~-浓度较对照组显著增高,P<0.05;ECP含量较对照组显著增高,P<0.05;不同时期哮喘患儿各组间诱导痰液中NO_3~-/NO_2~-含量和ECP均有显著性差异,P<0.05。哮喘患儿诱导痰液中NO_3~-/NO_2~-和ECP含量与1秒钟用力呼气容积占预计值百分比(FEV1.0％)呈显著负相关,r=0.512,P<0.01;而NO_3~-/NO_2~-含量与痰液中ECP浓度呈显著正相关r=0.607,P<0.01。提示NO参与了儿童哮喘的发生和发展,诱导痰液中NO_2~-/NO_2~-水平可反映气道炎症的变化,可用于儿童哮喘病情监测及指导药物治疗。     

尿白三烯E4检测在监测儿童支气管哮喘转归中的应用

目的 探讨尿白三烯E4(LTE4)检测在监测儿童支气管哮喘(哮喘)转归中的作用及哮喘患儿尿LTE4与呼吸道阻力(Rint)、外周血嗜酸性粒细胞(EOS)计数的关系.方法 选取30例1～5岁未服用过白三烯受体拮抗剂孟鲁司特钠的哮喘患儿(哮喘组),分为急性发作期、慢性持续期(服用孟鲁司特钠1个月)及临床缓解期(服用孟鲁司特钠3个月);另选取20例健康儿童作为健康对照组.采用竞争性ELISA法检测4组儿童尿LTE4水平,并测定Rint与EOS.结果 哮喘组急性发作期、慢性持续期及临床缓解期患儿尿LTE4及Rint水平均明显高于健康对照组(Pa＜0.01);3个哮喘组尿LTE4,Rint及外周血EOS比较差异均有统计学意义(F=870.08、496.58、195.98,Pa＜0.01).急性发作期哮喘患儿的尿LTE4水平与Rint无相关性(r=0.11,P＞0.05).与EOS亦无相关性(r=-0.12,P＞0.05).结论 哮喘患儿急性发作期尿LTE4水平明显升高,随着哮喘症状的好转,尿LTE4水平也逐渐下降;动态监测哮喘患儿尿LTE4水平,可以为儿童哮喘的临床诊断,白三烯受体拮抗剂治疗哮喘的疗效评估提供客观依据.     

1,25-（OH）2D3对哮喘小鼠肺内高迁移率族蛋白B1及Toll样受体4表达的影响

目的 观察1,25-（OH）2D3 对哮喘小鼠气道重塑、肺组织高迁移率族蛋白B1（HMGB1）及Toll样受体4（TLR4）表达的影响。方法 30 只雌性BALB/c 小鼠随机分为对照组、哮喘组和1,25-（OH）2D3 干预组。采用卵清蛋白腹腔注射致敏联合雾化吸入激发建立哮喘小鼠模型,干预组于每次激发前0.5 h 给予腹腔内注射1,25-（OH）2D3,对照组以生理盐水代替。苏木精-伊红染色观察小鼠气道结构变化;采用RT-PCR 法从mRNA水平及免疫组化法从蛋白质水平检测HMGB1 及TLR4 表达的变化;同时对相关变量进行Pearson 相关分析。结果 哮喘组气道壁厚度较对照组明显增厚,干预组较哮喘组气道壁增厚程度明显减轻（P<0.05）。哮喘组HMGB1、TLR4 的mRNA 和蛋白表达水平均较对照组增高（均P<0.05）;而干预组HMGB1、TLR4 的mRNA 和蛋白表达水平均较哮喘组降低,但仍高于对照组（均P<0.05）。肺组织内HMGB1 蛋白与TLR4 蛋白的表达呈正相关（P<0.01）,HMGB1 mRNA 及TLR4 mRNA 的表达亦呈正相关（P<0.01）。结论 在哮喘气道重塑模型中,HMGB1 及TLR4 可能参与哮喘气道重塑过程;1,25-（OH）2D3 可改善哮喘小鼠气道重塑,其机制可能与降低哮喘小鼠肺内HMGB1 及TLR4 的表达有关。     

哮喘患儿血清白细胞介素17、基质金属蛋白酶-9和免疫球蛋白E水平测定的意义

目的探讨哮喘患儿血清IL-17、基质金属蛋白酶-9（MMP-9）和IgE水平测定的意义。方法选取哮喘患儿28例为哮喘组,健康患儿14例为对照组。采用双抗体夹心酶联免疫吸附试验（SELISA）测定二组患儿血清IL-17、MMP-9及IgE水平,并行相关分析。结果哮喘组患儿血清IL-17、MMP-9和IgE水平均显著高于正常对照组（Pa〈0.01）。哮喘组患儿血清IL-17、MMP-9水平均与IgE呈显著正相关（r=0.395,0.940 P〈0.05,0.01）;而IL-17与MMP-9无相关关系（r=0.338 P〉0.05）。结论IL-17与MMP-9均参与哮喘患儿呼吸道炎症反应和呼吸道重建。     

Endotoxin exposure and symptoms in asthmatic children

Endotoxins (ET) are pro-innammatory substances present in hou.sc dust which may increase non-specific bronchial reactivity in asthmatic patients. Endotoxins (EU/g) and Der p I levels were compared in the homes often asthmatic and ten control children, aged 6-16 years, living in Sao Paulo, Brazil. The houses were visited once a month from February 1993 lo February 1994 and dust samples were collected from the bedding and floor of each subject's house. No significant differences were observed in ET and Derp 1 levels in the homes of asthmatics and controls. The highest ET levels were detected in January and November, whereas the lowest levels were detected in April and August (p < 0.05). demonstrating a distinct seasonal distribution. The highest Der p I levels in bedding were observed in July and the lowest in February (p < 0.05). while Derp I levels in floor did not show significant differences throughout the year. Symptom and medication scores were evaluated monthly in the group of asthmatic children. There was a significant correlation (p < 0.05. r = 0.63) between clinical symptom scores and ET exposure, however no significant correlation was found for mite exposure (p > 0.05. r = 0.19). The results suggest that ET exposure exacerbates asthmatic symptoms in mite allergic, asthmatic children.     

神经激肽A在哮喘患儿血浆含量变化的动态研究

目的　动态研究哮喘患儿血浆神经激肽A(NKA)含量变化规律 ,探讨NKA与小儿哮喘的关系。方法　用酶联免疫方法 ,动态测定 35例不同严重程度哮喘小儿血浆NKA在哮喘发作期及其临床症状缓解期的含量变化。结果　 (1 )小儿哮喘发作期血浆NKA含量 [(2 56± 1 53)ng/L]高于自身症状缓解期 [(70± 66)ng/L]及正常对照组 [(38± 6)ng/L] ,差异有非常显著意义 (q分别为9 497、8 599,P均 <0 0 1 ) ;哮喘症状缓解期血浆NKA含量较正常对照组差异无显著意义 (q =1 2 4 5 ,P >0 0 5)。 (2 )哮喘小儿病情加重 ,血浆NKA含量亦随之增高 ,重度哮喘发作时血浆NKA含量 [(2 96± 1 70 )ng/L]明显高于轻、中度哮喘发作时含量 [(1 90± 99)ng/L] ,差异有显著意义 (q =3 77,P <0 0 5)。结论　小儿哮喘发作期血中NKA含量明显增高 ,病情愈重增高越明显 ,随哮喘症状缓解血中NKA含量下降至正常水平 ;血中NKA含量的变化与小儿哮喘的发作及缓解关系密切     

哮喘儿童呼出气一氧化氮与肺功能及哮喘控制测试相关性研究

目的 探讨哮喘儿童呼出气一氧化氮（FeNO）水平与肺功能、哮喘控制测试（ACT）三者间的相关性及其在哮喘病情评估中的临床意义。方法 以2011年5月至2012年1月于中国医科大学附属盛京医院小儿哮喘门诊就诊的136例5～15岁哮喘儿童为研究对象,分别测定其FeNO水平、肺功能和ACT评分,分析三者间是否存在相关性。结果 FeNO水平与ACT评分水平呈负相关（r=-0.251,P＜0.005）。FeNO水平与肺功能FEV1/FVC（第1秒用力呼气容积/用力肺活量）呈负相关（r=-0.206,P＜0.05）,与FEV1及PEF不相关。ACT评分与肺功能FEV1/FVC呈正相关（r=0.242,P＜0.01）,与FEV1及PEF不相关。结论 针对所有研究对象,哮喘儿童FeNO水平与ACT评分呈负相关,与FEV1/FVC呈负相关, ACT与肺功能FEV1/FVC呈正相关,然而分组研究后,三者不具备稳定的相关性。FeNO评估哮喘儿童气道炎症,ACT评估哮喘患儿疾病控制水平,肺功能评价哮喘患儿气道阻塞情况,三者是从儿童哮喘的不同方面进行评估,互为补充,均具有重要临床意义,共同应用可提高儿童哮喘控制及诊治水平。     

Association of gastroesophageal reflux disease in young children with persistent respiratory symptoms

Forty children aged between 3 months and 3 years (median age 14 months) with persistent respiratory symptoms beyond 4 weeks or recurrence of respiratory symptoms were investigated for gastroesophageal reflux (GER). Diagnostic tests included upper gastrointestinal endoscopy, oesophageal biopsy, gastroesophageal scintiscan and 24 h ambulatory oesophageal pH monitoring. GER was detected in 14 (35 per cent) of these patients; which included 38 per cent of the enrolled cases of recurrent bronchopneumonia, 40 per cent cases of reactive airway disease, and 22 per cent cases of persistent cough. Amongst the cases detected to have GER, the age of onset of respiratory symptoms was less than 1 year in 86 per cent of cases (p < 0.01), nocturnal symptoms of cough and wheeze were reported in 78 per cent (p < 0.05), and 86 per cent cases did not present with typical gastrointestinal symptoms (p < 0.01). Family history of asthma was absent in all cases of GER-related reactive airway disease (p < 0.01). Cases detected to have GER were followed for 3-6 months after starting anti-reflux therapy. A significant (p < 0.01) decrease was noticed in the number of further episodes in children with GER-related recurrent bronchopneumonia and reactive airway disease after starting anti-reflux therapy. Improvement was also noticed in nocturnal symptoms and nutritional status after anti-reflux therapy was started. Our results suggest that GER may be one of the possible contributing factors in any child with recurrent and persistent respiratory complaints. Early diagnosis and anti-reflux therapy in cases with GER-related respiratory complaints can result in significant improvement in symptoms.     

Fluorocarbon ventilation: maximal expiratory flows and CO2 elimination

Elimination of CO2 during liquid ventilation is dependent on flow, diffusion, and the liquid's capacitance for CO2. Maximum expiratory flow (Vmax) and diffusion dead space were measured in vivo in 12 young cats during liquid fluorocarbon (FC-80) ventilation to determine the effect of breathing frequency on maximum CO2 elimination. All animals were maintained (PaO2 = 255 +/- 19 SEM mm Hg, PaCO2 = 35 +/- 1 SEM mm Hg, pH = 7.31 +/- 0.01 SEM) within physiologic range during 1-4 h of liquid ventilation. The Vmax in air (26 +/- 1 SEM liter/min) and in liquid (1.2 +/- 0.2 SEM liter/min) was determined by volume displacement plethysmography. Diffusion dead space (VDdiff) during liquid ventilation as a ratio of alveolar volume (VA) was well correlated (r = 0.84, p less than 0.005) with the average time (tav) the liquid was in the lung [VDdiff/VA = 0.89 e (-0.053 tav)]. Alveolar ventilation, CO2 elimination (VCO2), and PaCO2 were not affected by breathing frequency (f) when tidal volume was adjusted appropriately during steady state liquid ventilation. Predicted maximum CO2 elimination (VCO2max) determined from Vmax and VDdiff was 24 ml/min at a f of 3-3.5 breaths/min. The maximum was found to be strongly dependent on f with much less dependency on fixed dead space (anatomic plus equipment) and wave shape characteristics. Elimination of CO2 decreased at low values of f due to inadequate ventilation and at high values of f due to inadequate diffusion time. From a comparison of experimentally determined steady state VCO2 to theoretically predicted VCO2max, the results demonstrate a f-related functional reserve capacity for CO2 elimination during liquid ventilation.(ABSTRACT TRUNCATED AT 250 WORDS)     

Exhaled nitric oxide in childhood asthma

Endogenous synthesis of nitric oxide (NO) and its presence in exhaled air was observed in various species including humans. Particularly high levels were found in adults with bronchial asthma, possibly because of the underlying pulmonary inflammatory activity. We studied oral and nasal exhaled NO by chemiluminescence in 47 children aged between 6 and 10 years. Thirty children had bronchial asthma, 17 were healthy controls. In asthmatic children oral exhaled NO was 13.4±1.4 parts per billion (ppb) (mean±SEM), nasal exhaled NO was 21.7±1.5 ppb. In healthy controls oral exhaled NO was 7.2±1.0 ppb, nasal exhaled NO was 18.2±2.2 ppb. Oral exhaled NO was significantly higher in asthmatic children compared to healthy controls (P=0.0017). Nasal exhaled NO did not differ significantly in the two groups. There was a significant negative correlation between oral exhaled NO and forced expiratory volume in 1 s (FeV₁). No significant correlation between oral or nasal exhaled NO and other markers of obstructive lung function impairment, oral minute ventilation, the body mass index and the presence of upper respiratory tract infection could be found.     

Increased bronchial NO output in severe atopic eczema in children and adolescents.

Atopic children have an increased risk for asthma, which is preceded by bronchial inflammation. Exhaled nitric oxide (NO) measured at multiple exhalation flow rates can be used to assess alveolar NO concentration and bronchial NO flux, which reflect inflammation in lung periphery and central airways, respectively. Exhaled breath condensate is another non-invasive method to measure lung inflammation. The purpose of the present study was to find out if the severity of atopic eczema is associated with lung inflammation that can be observed with these non-invasive tests. We studied 81 patients (7-22 yr old) with atopic eczema and increased wheat-specific IgE (>or=0.4 kUA/l) and no diagnosis of asthma. Exhaled NO was measured at multiple exhalation flow rates, and bronchial NO flux and alveolar NO concentration were calculated. Cysteinyl-leukotriene concentrations were measured in exhaled breath condensate. The patients were divided into two groups according to the severity of atopic eczema. Patients with severe atopic eczema had enhanced bronchial NO output as compared with patients with mild eczema (2.1 +/- 0.5 vs. 0.9 +/- 0.1, p = 0.003). No statistically significant differences in alveolar NO concentrations were found between the groups. In the whole group of patients, the bronchial NO output correlated positively with serum eosinophil protein X (r(s) = 0.450, p < 0.001), serum eosinophil cationic protein (r(s) = 0.393, p < 0.001), serum total IgE (r(s) = 0.268, p = 0.016) and with urine eosinophil protein X (r(s) = 0.279, p = 0.012), but not with lung function. Alveolar NO concentration correlated positively with serum eosinophil protein X (r(s) = 0.444, p < 0.001) and with serum eosinophil cationic protein (r(s) = 0.362, p = 0.001). Measurable cysteinyl-leukotriene concentrations in exhaled breath condensate were found only in one-third of the patients, and there were no differences between the two groups. The results show that increased bronchial NO output is associated with eosinophilic inflammation and severe atopic eczema in patients without established asthma.     

血清Clara 细胞分泌蛋白、总IgE与嗜酸性粒细胞阳离子蛋白在儿童哮喘检测中的临床意义

目的探讨血清Clara细胞分泌蛋白（CC16）、总IgE和嗜酸性粒细胞阳离子蛋白（ECP）检测在哮喘儿童中的意义。方法采用酶联免疫吸附法（ELISA）测定59例哮喘患儿急性发作期血清CC16水平,同时应用UniCAP100变态反应检测仪检测血清总IgE、ECP;另设30例健康儿童作为健康对照组。结果与健康对照组比较,哮喘组血清CC16水平显著降低、血清总IgE、ECP水平显著增高（t=2.93,2.72,4.52Pa〈0.01）;中重度哮喘发作患儿血清CC16水平显著低于轻度发作患儿（t=5.26P〈0.05）,中重度哮喘发作患儿血清总IgE显著高于轻度发作患儿（t=3.89P〈0.05）,血清ECP水平在哮喘轻度发作组与中重度发作组比较无统计学差异（t=1.57P〉0.05）;哮喘组血清CC16与总IgE呈显著负相关（r=-0.602P〈0.05）,血清CC16与ECP（r=0.153P〉0.05）及总IgE与ECP（r=0.290P〉0.05）无相关。结论血清CC16降低与总IgE、ECP水平增高在儿童哮喘发病过程中发挥重要作用;血清总IgE、CC16可反映哮喘发作严重程度;血清ECP水平高低并不能反映呼吸道炎症严重程度。     

Circadian variation of exhaled nitric oxide and urinary eosinophil protein X in asthmatic and healthy children.

Asthmatic symptoms and the frequency of admissions to hospital because of acute asthma tend to increase in the early morning hours, and it is therefore possible that airway inflammation increases during the night. To elucidate the hypothetical circadian variation of airway inflammation, we measured concentrations of exhaled nitric oxide (FeNo), urinary eosinophil protein X excretion (EPX), and forced expiratory volume in the first second (FEV1) in 20 asthmatic and 6 nonatopic nonasthmatic children every 3 h during a 21-h period. Compared with control subjects, asthmatic subjects had higher FeNo (median, 22.7 versus 10.3 ppb, p = 0.016) and lower FEV1 % predicted (median, 91.0 versus 101.9%, p = 0.045), but did not differ significantly in EPX (median, 153.8 versus 148.7 microg/mmol creatinine, p = 0.83) at 7 AM. However, differences in gender and age do not allow direct comparisons between asthmatic and control children. FeNo and EPX demonstrated a cosinelike circadian rhythm (log FeNo, p = 0.0001; log EPX, p = 0.0001) with lowest levels at 7 PM and highest at 7 AM. This was also the case for FEV1 % (p = 0.01). No difference in the amplitude of circadian rhythm was observed between asthmatic and healthy control children for log FeNo (p = 0.35), log EPX (p = 0.57), and FEV1 % (p = 0.17). A stratified analysis showed a significant circadian rhythm in the control group for log FeNo (p = 0.014) and log EPX (p = 0.0001). Our results therefore suggest a circadian rhythm of inflammatory markers, which peaks in the early morning. Rhythmicity of EPX excretion and FeNo in healthy children suggests a physiologic mechanism; however, pathologic effects during the night might occur under conditions of asthma-specific inflammation.