发作期哮喘儿童NO,NOS,MDA与肺功能的关系

目的　探讨儿童哮喘发作时血清一氧化氮 (NO)、一氧化氮合酶 (NOS)、丙二醛 (MDA)活性变化及与肺功能的关系。方法　分别测定 4 3例哮喘患儿 (哮喘组 )和 30例健康儿童 (对照组 )血清NO ,NOS ,MDA活性 ,进行统计学比较 ;测定 36例不同程度哮喘患儿血清NO ,NOS ,MDA活性及肺功能 ,与对照组和缓解组对比并进行相关性分析。结果　哮喘组血清NO ,NOS值明显高于对照组 (P <0 .0 0 1) ,MDA值亦高于对照组 (P <0 .0 5 )。与对照组血清NO ,NOS ,MDA值比较 ,轻度哮喘组无统计学意义 (P >0 .0 5 ) ;中度哮喘组具显著性意义 (NO ,NOS值P <0 .0 0 1,MDA值P <0 .0 5 ) ;重度哮喘组具高度显著性意义 (P <0 .0 0 1)。与缓解组第 1秒用力呼气流量(FEV1)、5 0 %肺活量时最大呼气流量 (FEF50 )比较 ,轻度哮喘组无统计学意义 (P >0 .0 5 ) ;中度哮喘组具高度显著性意义 (P <0 .0 0 1) ;重度哮喘组具高度显著性意义 (P <0 .0 0 1)。血清NO ,NOS ,MDA值与FEV1,FEF50 间存在正相关关系。结论　NO自由基和脂质过氧化物活性增强参与儿童哮喘的发病 ,哮喘程度越重 ,血清NO ,NOS ,MDA活性越高 ,而肺功能受损越重。     

呼气中一氧化氮监测在儿童哮喘的临床应用

目的 评估呼气中一氧化氮(FeNO)监测在儿童哮喘的价值, 为更好控制和监测哮喘病情提供帮助。方法 随机选取就诊于福州儿童医院变态反应科的轻、中、重度哮喘儿童50例为实验组, 分别在治疗3个月和治疗6个月进行随访、评估病情。随访时记录日、夜间哮喘症状评分、FeNO和肺功能。同期随机选择50例健康对照组给予检测FeNO。结果 1)实验组治疗3个月FeNO值较治疗前显著降低, 差异有统计学意义(P＜0.000 1), 与治疗6个月比较, 差异无统计学意义(P＞0.05)。2)实验组FeNO值和日、夜间哮喘症状评分在治疗3个月、治疗6个月呈明显下降;肺功能各参数FEV1%、FVC和PEF值在治疗3个月、治疗6个月呈明显升高, 差异有统计学意义(P＜0.05)。3)实验组治疗前、后FeNO值明显高于健康对照组(P＜0.000 1)。结论 FeNO可以作为一项很好的指标来评估哮喘患儿的气道炎症。     

Differential oxidative stress response in young children and the elderly following exposure to PM2.5

Objectives  The mechanism of the adverse health effects of ambient particulate matter on humans has not been well-investigated despite many epidemiologic association studies. Measurement of personal exposure to particulate pollutants and relevant biological effect markers are necessary in order to investigate the mechanism of adverse health effects, particularly in fragile populations considered to be more susceptible to the effects of pollutants. Methods  We measured personal exposure to PM_2.5 and examined oxidative stress using urinary malondialdehyde three times in 51 preschoolers and 38 elderly subjects. A linear mixed-effects model was used to estimate PM_2.5 effects on urinary MDA levels. Results  Average personal exposure of the children and elderly to PM_2.5 was 80.5 ± 29.9 and 20.7 ± 12.7 μg/m³, respectively. Mean urinary MDA level in the children and the elderly was 3.6 ± 1.9 and 4.0 ± 1.6 μmol/g creatinine. For elderly subjects the PM_2.5 level was significantly associated with urinary MDA after adjusting for age, sex, BMI, passive smoking, day-care facility site, alcohol consumption, cigarette smoking, and medical history (heart disease, hypertension and bronchial asthma). However, there was no significant relationship for children. Conclusions  The elderly were more susceptible than young children to oxidative stress as a result of ambient exposure to PM_2.5. Identification of oxidative stress induced by PM_2.5 explains the mechanism of adverse health effects such as cardiovascular or respiratory diseases, particularly in the elderly.     

杭州地区门诊哮喘患儿比例与PM2.5和气温的相关性研究

目的 研究杭州地区门诊儿童哮喘流行病学特征及其与PM2.5和气温的关系,为哮喘的预防控制提供依据。方法 收集2015-2019年浙江大学医学院附属儿童医院门诊哮喘患儿就诊信息,采集2015-2019年每日的天气信息记录并和哮喘门诊量进行相关性分析。结果 2015-2019年,本院门诊有784 137例患儿被诊断为哮喘,3岁以下患儿是哮喘的主要人群,占总人数的49.66%,7岁以下儿童占总人数的84.38%;秋冬季节的哮喘发病率明显高于其他季节。哮喘就诊患儿的门诊数量和PM2.5浓度和气温存在相关性,与PM2.5浓度呈正相关(r＝0.237,P<0.001),而与日最高气温(r=-0.436)、日最低气温(r＝-0.418)、日温差(r=-0.433)、日平均气温(r=-0.433)均呈负相关(P<0.01)。结论 学龄前儿童哮喘发生率更高,患儿家长应该在气温较低和PM2.5较高的秋冬季节密切关注患儿的身体情况,防止重型哮喘疾病的发生。     

杭州地区门诊哮喘患儿比例与PM2.5和气温的相关性研究

目的 研究杭州地区门诊儿童哮喘流行病学特征及其与PM2.5和气温的关系,为哮喘的预防控制提供依据。方法 收集2015-2019年浙江大学医学院附属儿童医院门诊哮喘患儿就诊信息,采集2015-2019年每日的天气信息记录并和哮喘门诊量进行相关性分析。结果 2015-2019年,本院门诊有784 137例患儿被诊断为哮喘,3岁以下患儿是哮喘的主要人群,占总人数的49.66%,7岁以下儿童占总人数的84.38%;秋冬季节的哮喘发病率明显高于其他季节。哮喘就诊患儿的门诊数量和PM2.5浓度和气温存在相关性,与PM2.5浓度呈正相关(r＝0.237,P<0.001),而与日最高气温(r=-0.436)、日最低气温(r＝-0.418)、日温差(r=-0.433)、日平均气温(r=-0.433)均呈负相关(P<0.01)。结论 学龄前儿童哮喘发生率更高,患儿家长应该在气温较低和PM2.5较高的秋冬季节密切关注患儿的身体情况,防止重型哮喘疾病的发生。     

呼出气一氧化氮检测对儿童哮喘的临床意义

目的探讨呼出气一氧化氮(ENO)检测在儿童哮喘控制评估中的临床价值。方法 120例哮喘患儿,根据儿童哮喘控制测试(C—ACT)评分,分为哮喘未控制组(C—ACT<20分)50例和哮喘控制组(C—ACT≥20分)70例;120例哮喘患儿,根据2014版GINA指南分为重度组38例、中度组46例及轻度组36例、30例健康儿童为对照组。所有研究对象均进行ENO和肺功能(FEV1%、PEF%)检测,分析ENO水平与FEV1%、PEF%的相关性。结果哮喘控制组、非控制组及对照组3组组间ENO水平比较差异均有统计学意义(F=90.72,P<0.05);重度组、中度组、轻度组及对照组4组纽间ENO水平差异具有统计学意义(F=1123.78,P<0.05);哮喘非控制组、控制组、重度组、中度组和轻度组ENO水平与肺功能FEV1%和PEF%均无相关性(r值介于-0.097^-0.027,均P>0.05)。结论 ENO是气道炎症反应的良好指标,可作为监测儿童哮喘严重程度及控制状况的指标。     

Personal and ambient air pollution is associated with increased exhaled nitric oxide in children with asthma

BACKGROUND: Research has shown associations between pediatric asthma outcomes and airborne particulate matter (PM). The importance of particle components remains to be determined. METHODS: We followed a panel of 45 schoolchildren with persistent asthma living in Southern California. Subjects were monitored over 10 days with offline fractional exhaled nitric oxide (FeNO), a biomarker of airway inflammation. Personal active sampler exposures included continuous particulate matter < 2.5 microm in aerodynamic diameter (PM2.5), 24-hr PM2.5 elemental and organic carbon (EC, OC), and 24-hr nitrogen dioxide. Ambient exposures included PM2.5, PM2.5 EC and OC, and NO2. Data were analyzed with mixed models controlling for personal temperature, humidity and 10-day period. RESULTS: The strongest positive associations were between FeNO and 2-day average pollutant concentrations. Per interquartile range pollutant increase, these were: for 24 microg/m3 personal PM2.5, 1.1 ppb FeNO [95% confidence interval (CI), 0.1-1.9]; for 0.6 microg/m3 personal EC, 0.7 ppb FeNO (95% CI, 0.3-1.1); for 17 ppb personal NO2, 1.6 ppb FeNO (95% CI, 0.4-2.8). Larger associations were found for ambient EC and smaller associations for ambient NO2. Ambient PM2.5 and personal and ambient OC were significant only in subjects taking inhaled corticosteroids (ICS) alone. Subjects taking both ICS and antileukotrienes showed no significant associations. Distributed lag models showed personal PM2.5 in the preceding 5 hr was associated with FeNO. In two-pollutant models, the most robust associations were for personal and ambient EC and NO2, and for personal but not ambient PM2.5. CONCLUSION: PM associations with airway inflammation in asthmatics may be missed using ambient particle mass, which may not sufficiently represent causal pollutant components from fossil fuel combustion.     

Exhaled nitric oxide in the diagnosis and monitoring of lung diseases

In recent 10 years there has been an explosion of interest in the analysis of breath constituents as a way of monitoring airway inflammation in lung diseases. Monitoring of inflammation may assist in differential diagnosis of lung diseases, assessment of their severity and response to appropriate treatment. Among these novel non-invasive methods, exhaled nitric oxide has been the most extensively studied. Its measurement has recently been standardized, and there are now commercially available nitric oxide analyzers. Concentration of exhaled nitric oxide is markedly elevated in asthma, and its elevation is positively related to the degree of eosinophilic airway inflammation, airway hyperresponsiveness and symptoms. Furthermore, evidence suggests that exhaled nitric oxide-driven asthma treatment provides more precise asthma control compared to conventional treatment protocols. With regard to other lung diseases, in chronic obstructive pulmonary disease exhaled nitric oxide may be useful in predicting steroid responsiveness, while in lung transplant recipients its measurement could contribute to the detection of asymptomatic infections and rejection processes.     

Exhaled nitric oxide: sources of error in offline measurement

Delayed offline measurement of exhaled nitric oxide (eNO), although useful in environmental and clinical research, is limited by the instability of stored breath samples. The authors characterized sources of instability with the goal of minimizing them. Breath and other air samples were stored under various conditions, and NO levels were measured repeatedly over 1-7 d. Concentration change rates varied positively with temperature and negatively with initial NO level, thus "stable" levels reflected a balance of NO-adding and NO-removing processes. Storage under refrigeration for a standardized period of time can optimize offline eNO measurement, although samples at room temperature are effectively stable for several hours.     

Effect of environmental interventions to reduce exposure to asthma triggers in homes of low-income children in Seattle

The effectiveness of community health workers (CHWs) assisting families in reducing exposure to indoor asthma triggers has not been studied. In all, 274 low-income asthmatic children were randomly assigned to high- or low-intensity groups. CHWs visited all homes to assess exposures, develop action plans and provide bedding encasements. The higher-intensity group also received cleaning equipment and five to nine visits over a year focusing on asthma trigger reduction. The asthma trigger composite score decreased from 1.56 to 1.19 (Delta=-0.37, 95% CI 0.13, 0.61) in the higher-intensity group and from 1.63 to 1.43 in the low-intensity group (Delta=-0.20, 95% CI 0.004, 0.4). The difference in this measure due to the intervention was significant at the P=0.096 level. The higher-intensity group also showed improvement during the intervention year in measurements of condensation, roaches, moisture, cleaning behavior, dust weight, dust mite antigen, and total antigens above a cut point, effects not demonstrated in the low-intensity group. CHWs are effective in reducing asthma trigger exposure in low-income children. Further research is needed to determine the effectiveness of specific interventions and structural improvements on asthma trigger exposure and health.     

Personal PM2.5 exposure and markers of oxidative stress in blood

Ambient particulate air pollution assessed as outdoor concentrations of particulate matter less than or equal to 2.5 micro m in diameter (PM(2.5)) in urban background has been associated with cardiovascular diseases at the population level. However, the significance of individual exposure and the involved mechanisms remain uncertain. We measured personal PM(2.5) and carbon black exposure in 50 students four times in 1 year and analyzed blood samples for markers of protein and lipid oxidation, for red blood cell (RBC) and platelet counts, and for concentrations of hemoglobin and fibrinogen. We analyzed protein oxidation in terms of gamma-glutamyl semialdehyde in hemoglobin (HBGGS) and 2-aminoadipic semialdehyde in hemoglobin (HBAAS) and plasma proteins (PLAAS), and lipid peroxidation was measured as malondialdehyde (MDA) in plasma. Median exposures were 16.1 micro g/m(3) for personal PM(2.5) exposure, 9.2 micro g/m(3) for background PM(2.5) concentration, and 8.1 X 10(-6)/m for personal carbon black exposure. Personal carbon black exposure and PLAAS concentration were positively associated (p < 0.01), whereas an association between personal PM(2.5) exposure and PLAAS was only of borderline significance (p = 0.061). A 3.7% increase in MDA concentrations per 10 micro g/m(3) increase in personal PM(2.5) exposure was found for women (p < 0.05), whereas there was no significant relationship for the men. Similarly, positive associations between personal PM(2.5)exposure and both RBC and hemoglobin concentrations were found only in women (p < 0.01). There were no significant relationships between background PM(2.5) concentration and any of the biomarkers. This suggests that exposure to particles in moderate concentrations can induce oxidative stress and increase RBCs in peripheral blood. Personal exposure appears more closely related to these biomarkers potentially related to cardiovascular disease than is ambient PM(2.5) background concentrations.     

不同微环境PM_(2.5)个体暴露量的初步研究

目的调查PM_(2.5)个体暴露水平,评估不同微环境的PM_(2.5)暴露量。方法于2014年10—11月在北京市招募时间-活动模式较为规律的7名办公室职员为调查对象,采用PM_(2.5)个体暴露追踪监测结合日志记录时间-活动模式的方式开展为期12 d的研究。结果调查对象在家、办公室和交通微环境(步行、公交车、地铁、私家车、出租车、自行车)的日均暴露时间分别为13.1、6.0、2.7 h;24 h的PM_(2.5)个体暴露日均浓度为119μg/m~3,家、办公室和交通微环境的PM_(2.5)暴露日均浓度分别为105、127、152μg/m~3;24 h PM_(2.5)个体暴露量为119μg/(m~3·d),家、办公室和交通的PM_(2.5)暴露量分别为61、32、13μg/(m~3·d),三种微环境的PM_(2.5)暴露量之和占总暴露量的67.6%~100%。结论调查人群的PM_(2.5)个体暴露水平较高,应予以高度重视;家、办公室和交通是主要的PM_(2.5)暴露环境,应对PM_(2.5)污染应优先考虑采取干预措施。     

呼出气一氧化氮监测在儿童哮喘吸入性糖皮质激素治疗中的应用

目的 探究呼出气一氧化氮(FeNO)含量监测在儿童哮喘吸入性糖皮质激素(ICS)治疗中的应用价值.方法 选取2017年3月-2019年4月永康市妇幼保健院收治的84例行ICS治疗的儿童哮喘患儿为研究对象,根据随机数字表法分为观察组和对照组,每组各42例.对照组患儿根据哮喘控制水平分级进行临床治疗方案的调整,观察组患儿在...     

Effects of short-term exposure to 0.2 ppm ozone on biomarkers of inflammation in sputum, exhaled nitric oxide, and lung function in subjects with mild atopic asthma

To gain further insight into the kinetics of airway inflammatory response and explore the possibility of nitric oxide as a surrogate marker of the lower airway inflammatory response to ozone, nine subjects with mild atopic asthma were exposed to filtered air or 0.2 ppm ozone for 2 hours with intermittent exercise. Lung function was measured at baseline and immediately after exposures. Sputum induction was performed at 6 hours and at 24 hours after exposures, and exhaled nitric oxide levels were measured at baseline, immediately, 6, and 24 hours after both exposures. A significant decline in forced expiratory volume in one second and inspiratory capacity was detectable following exposure to ozone. In addition, a 2-fold increase was observed in the percentage of polymorphonuclear leukocytes 6 hours after exposure to ozone, with no changes in other biomarkers at this time point. By 24 hours after ozone exposure, the neutrophilia had subsided but there was an increase in albumin, total protein, myeloperoxidase, and eosinophil cationic protein. Exhaled nitric oxide levels, histamine, interleukin-8, and growth-related oncogene-alpha in sputum did not change significantly following ozone exposure. It was concluded that short-term ozone exposure induces an acute inflammatory response in asthmatic airways, characterized by early polymorphonuclear leukocyte influx followed by plasma extravasation and activation of eosinophils and neutrophils. Exhaled nitric oxide is not a useful marker for detecting inflammatory response to ozone in persons with mild asthma.     

Exhaled nitric oxide measurement in workers in a microwave popcorn production plant

Airways obstruction in microwave-popcorn workers has been attributed to inhalation of flavoring agents. Two former workers at a microwave-popcorn plant were found by lung biopsy to have bronchiolitis obliterans. The study's aim was to determine whether exhaled nitric oxide (FENO) levels were associated with exposure levels, respiratory symptoms, or airways obstruction. A questionnaire, spirometry, and FENO measurements were completed by 135 workers. The FENO levels of workers with high flavoring exposures (n = 107) were compared with those of workers with low exposures (n = 28) and healthy external controls (n = 31). FENO levels were significantly lower in the high-exposure group (p < 0.05). There is no indication that FENO is useful as a marker of lung injury in a flavoring-exposed worker population with a substantial lung disease burden, but the finding of low FENO in the high-exposure group should not be dismissed.     

不同工作环境人群PM2.5暴露水平与肺功能的研究

目的评价太原市交通警察和疾病预防控制中心(CDC)人员工作环境PM2.5暴露水平,探讨工作环境PM2.5暴露与人群肺功能的关系。方法选用外勤交通警察(暴露组)、CDC人员(对照组)为研究对象,应用环境检测和时间-活动日记相结合的方法连续采样1周,计算研究对象工作时间内PM2.5暴露剂量和潜在暴露剂量。同时对研究对象进行问卷调查,于环境PM2.5检测1周结束后检测肺功能。结果交通警察工作交通路口的PM2.5浓度([0.132±0.049)mg/m3]高于CDC办公室内PM2.5浓度([0.100±0.044)mg/m3],交通警察8 h工作时间内的暴露剂量、潜在暴露剂量分别为(1.060±0.23)mg和(1.690±0.37)mg,均高于CDC人员[均为(0.798±0.19)mg];男性交通警察最大呼气流量(PEF)和第1秒钟用力呼气量/用力肺活量(FEV1.0/FVC)分别为(4.70±0.28)L/s和0.82±0.03,低于男性CDC人员[PEF和FEV1.0/FVC分别为(6.53±0.41)L/s和0.92±0.02];上述差异均有统计学意义(P0.05)。结论交通警察的PM2.5暴露剂量和潜在暴露剂量均高于CDC人员,男性交通警察的肺功能下降可能与长期暴露于机动车尾气有关。