Increased exhaled 8-isoprostane in childhood asthma

STUDY OBJECTIVE: To quantify lung oxidative stress in asthmatic children by measuring concentrations of 8-isoprostane, a marker of oxidative stress, in exhaled breath condensate (EBC), which is a noninvasive method of sampling airway secretions. Secondary objectives were as follows: (1) to measure levels of exhaled prostaglandin (PG) E(2), since impaired PGE(2) production has been implicated in the pathogenesis of asthma in adults; and (2) to measure levels of fractional exhaled nitric oxide (FeNO), which is a marker of airway inflammation. DESIGN: Single-center, cross-sectional study. PATIENTS: Twelve healthy children, 12 steroid-na?ve asthmatic children, and 30 children in stable condition with mild-to-moderate persistent asthma who were being treated with inhaled corticosteroids (ICSs) [average dose, 300 micro g per day] were studied. INTERVENTIONS: Subjects attended the outpatient clinic on one occasion for the collection of EBC and FeNO measurements. Measurements and results: 8-Isoprostane and PGE(2) concentrations in EBC were measured with specific radioimmunoassays. FeNO was measured online by a chemiluminescence analyzer. 8-Isoprostane was detectable in the EBC of healthy children (mean [+/- SEM], 34.2 +/- 4.5 pg/mL), and its concentrations were increased in both steroid-na?ve asthmatic children (mean, 56.4 +/- 7.7 pg/mL; p < 0.01) and steroid-treated asthmatic children (mean, 47.2 +/- 2.3 pg/mL; p < 0.05). There was no difference in exhaled 8-isoprostane concentrations between the two groups of asthmatic children (p = 0.14). By contrast, exhaled PGE(2) concentrations were similar among the three study groups (p = 0.56). FeNO levels were higher in steroid-na?ve children with asthma (49.2 +/- 9.6 parts per billion [ppb]; p < 0.05) and, to a lesser extent, in steroid-treated asthmatic children (37.8 +/- 6.6 ppb; p < 0.05) compared with healthy children (15.2 +/- 1.7 ppb). CONCLUSIONS: Lung oxidative stress is increased in children who are in stable condition with asthma, as reflected by increased exhaled 8-isoprostane concentrations. This increase seems to be relatively resistant to treatment with ICSs. Decreased PGE(2) lung production is unlikely to play a pathophysiologic role in childhood asthma.     

Increased 8-isoprostane, a marker of oxidative stress, in exhaled condensate of asthma patients.

Oxidative stress has an important role in the pathogenesis of asthma. 8-Isoprostane is a prostaglandin (PG)-F2-like compound belonging to the F2 isoprostane class that is produced in vivo by the free radical-catalyzed peroxidation of arachidonic acid. 8-Isoprostane is a biomarker of oxidative stress, and its concentration is increased in the bronchoalveolar lavage fluid of patients with interstitial lung diseases. We measured 8-isoprostane concentrations in exhaled breath condensate in healthy subjects and in patients with mild (steroid naive, n = 12), moderate (inhaled steroid treatment, n = 17), and severe asthma (oral steroid treatment, n = 15). We also measured exhaled carbon monoxide (CO) and nitric oxide (NO), which may also reflect oxidative stress in the airways. 8-Isoprostane was detectable in breath condensate of normal subjects (15.8 +/- 1.6 pg/ml), and was increased in the breath condensate of patients with mild (33.7 +/- 2.8, p < 0.001), moderate (38.3 +/- 3.7 pg/ml, p < 0. 001), and severe asthma (48.9 +/- 5.0 pg/ml, p < 0.001). There was a positive correlation (r = 0.68, p < 0.05) of 8-isoprostane with NO, but not with CO, in the exhaled air of patients with mild asthma, but not in that of patients with moderate or severe asthma. There was no correlation between 8-isoprostane and lung function tests in any group of patients. Our study shows that oxidative stress is increased in asthmatic subjects as reflected by 8-isoprostane concentrations in breath condensate.     

呼出气冷凝液中8-异前列腺素水平检测对咳嗽变异性哮喘的临床意义

目的探讨8-异前列腺素检测对诊治咳嗽变异性哮喘(CVA)的临床意义。方法选取50例CVA患者和30例健康对照纳入研究,所有受试者测定呼出气冷凝液中8-异前列腺素水平并进行肺功能检测。结果与健康人群相比,CVA患者EBV中8-iso-PG水平显著升高(P0.01);治疗前后比较,CVA患者EBV中8-iso-PG水平明显降低(P0.01),而FEV1%检测差异无统计学意义。EBV中8-iso-PG水平与FEV1%检测值之间无相关性(r=-0.17,P0.05)。结论 EBC中8-iso-PG检测可直观反映CVA患者存在的气道氧化应激状态,并能较好的预测治疗敏感性,从而有助于CVA患者的早期诊断和疗效预判。     

Relationship between exhaled leukotriene and 8-isoprostane levels and asthma severity,asthma control level,and asthma control test score

ObjectiveExhaled breath condensate (EBC) is a completely non-invasive method for the collection of airway secretions to measure intense inflammation in the airways of asthmatics. It has been shown that the childhood asthma control test (c-ACT) is a good tool for use in the evaluation of asthmatics. Whether the c-ACT score and asthma control level correlate with the airway inflammation is not well known. We aimed to evaluate the relationship between exhaled cysteinyl leukotrienes (Cys-LTs) and 8-isoprostane levels and asthma severity, asthma control level and c-ACT score in asthmatic children.MethodsThirty asthmatic children were evaluated with c-ACT score and pulmonary function tests. Asthma severity and asthma control level were assessed according to GINA. EBC was collected and Cys-LTs and 8-isoprostane concentrations were determined using a specific immunoassay kit.ResultsExhaled 8-isoprostane level in patients with moderate persistent asthma [114 (55–146) pg/ml] was higher than in the mild persistent group [52 (21–91) pg/ml] (p = 0.05, Mann–Whitney U [MWU]). EBC 8-isoprostane in children with 1–4 asthma exacerbations/year [52 (16–80) pg/ml] was significantly lower than in children with >4 asthma exacerbations/year [114 (57–129) pg/ml] (p < 0.05, MWU). No significant relation was determined between exhaled 8-isoprostane and Cys-LTs levels and c-ACT score and asthma control level. Exhaled 8-isoprostane correlated negatively with bronchodilator response (p = 0.015, r = −0.45).ConclusionsExhaled 8-isoprostane, as an oxidative stress specifier, was found to be increased in relation with asthma exacerbation frequency and oxidative stress increases with the severity of asthma. In contrast to asthma severity level, c-ACT score and asthma control level may not reflect airway inflammation.     

呼出气冷凝液中8-异前列腺素F2α的检测及其临床意义

8-异前列腺素F2α是目前研究比较多的一种呼出气中的标志物，反映了呼吸系统疾病炎症反应及氧化应激变化，有较好特异性及灵敏度。本文就呼出气冷凝液中8-异前列腺素F2α的来源、代谢、检测方法、影响呼出气中8-异前列腺素F2α水平的因素和临床意义等进行综述。     

Quantitative analysis of 8-isoprostane and hydrogen peroxide in exhaled breath condensate.

Exhaled breath condensate (EBC) provides a noninvasive means of sampling the lower respiratory tract. Collection of EBC might be useful in the assessment of airway oxidative stress in smokers. The aim of this study was to determine 8-isoprostane and hydrogen peroxide levels in EBC, and, in addition, to investigate the reproducibility of these measurements. EBC samples were collected from 12 healthy male smokers at three time points within 1 week. 8-isoprostane and H2O2 were measured in nonconcentrated EBC using immunochemical and colorimetric assays, respectively. 8-isoprostane and H2O2 were detected in only 36 and 47% of all EBC samples, respectively. It was not possible to calculate the within-subject variation in a reliable manner since only three of the 12 smokers exhibited detectable 8-isoprostane concentrations on all three occasions (mean 4.6 pg x mL(-1); range 3.9-7.7 pg x mL(-1)), whereas H2O2 could not be detected on all three occasions in any of the smokers. Spiking experiments revealed a recovery of 83.5-109.5% for 8-isoprostane and 69.9-129.0%, for H2O2 in fresh EBC samples. It was concluded that levels of 8-isoprostane and hydrogen peroxide cannot be reproducibly assessed in exhaled breath condensate from healthy smokers because of their low concentration and/or the lack of sensitivity of the available assays.     

Variability of exhaled breath condensate leukotriene B4 and 8-isoprostane in COPD patients

The reproducibility of exhaled breath condensate (EBC) mediators is not well documented in chronic obstructive pulmonary disease (COPD). This study assessed within assay (WA), within (WD) and between day (BD) reproducibility of EBC leukotriene B₄ (LTB₄) and 8-isoprostane. Three EBC samples were collected from 24 COPD patients separated by 1 h and 1 wk, to assess WD and BD reproducibility. WA reproducibility was assessed by sample analysis by enzyme immunoassay in triplicate. WA coefficient of variation for LTB₄ and 8-isoprostane (18.2% and 29.2%, respectively) was lower than corresponding values for WD (47.7% and 65.3%, respectively) and BD (75.7% and 79.1%, respectively). Repeatability coefficient for 8-isoprostane and LTB₄ assays were 18.6 pg/ml and 13.2 pg/ml, respectively. Group mean differences for WD and BD were small and statistically nonsignificant. Using the Bland Altman method, there were wide limits of agreement for WD (−51.6 to 47.2 for 8-isoprostane and −31.8 to 31.4 for LTB₄) and BD reproducibility (−61.4 to 75.7 for 8-isoprostane and −29.3 to 38.6 for LTB₄). This is the first study to fully report the variability of EBC 8-isoprostane and LTB₄ in COPD. WA variability and group mean changes were small. However, we observed considerable WD and BD variability for these biomarkers.     

Increased leukotrienes in exhaled breath condensate in childhood asthma

Cysteinyl leukotrienes (cys-LTs; LTC4, LTD4, and LTE4) are generated predominantly by mast cells and eosinophils and induce airway smooth muscle contraction, microvascular leakage, and mucous hypersecretion whereas leukotriene B4 (LTB4) is a potent chemoattractant of neutrophils. We measured cys-LTs and LTB4 in exhaled breath condensate from children aged 7-14 years including healthy nonatopic children (n = 11) and children with mild intermittent asthma (steroid naive, n = 11), mild persistent asthma (low-dose inhaled steroid treatment, n = 13), or moderate to severe persistent asthma (high-dose inhaled steroid treatment, n = 13). Exhaled LTB4 levels were increased in patients with mild and moderate to severe persistent asthma compared with patients with mild intermittent asthma (126.0 +/- 8.8 and 131.9 +/- 7.1 versus 52.7 +/- 3.8 pg/ml, p < 0.001 and p < 0.0001) and normal subjects (126.0 +/- 8.8 and 131.9 +/- 7.1 versus 47.9 +/- 4.1 pg/ml, p < 0.0001). Elevated exhaled cys-LT levels were found in patients with mild and moderate to severe persistent asthma compared with normal subjects (27.9 +/- 2.8 and 31.5 +/- 4.5 versus 18.5 +/- 0.5 pg/ml, p < 0.01 and p < 0.05). There was an inverse correlation between exhaled cys-LTs and LTB4 in patients with mild persistent asthma. We conclude that exhaled cys-LTs and LTB4 may be noninvasive markers of airway inflammation in pediatric asthma.     

呼出气冷凝液中NO、8-异前列腺素与哮喘严重程度关系

目的分析支气管哮喘患者呼出气冷凝液(EBC)中一氧化氮(NO)、8-异前列腺素(8-isoprostane)浓度与肺功能、ACT变化之间的关系。方法病例对照研究。结果 36例患者参加了本次研究,慢性持续期26例、缓解期10例,健康对照19例。缓解期、慢性持续期及健康对照组之间,8-isoprostane、NO与FEV1/pre、ACT评分有统计学差异(P<0.01)。FEVl/pre与NO、8-isoprostane存在负相关性(r=-0.610,P<0.05;r=-0.545,P<0.05)。ACT与NO、8-isoprostane也呈现负相关(r=-0.533,P<0.05;r=-0.584,P<0.05)。结论 EBC中炎性标志物能反映出气道炎症程度,且与肺功能和ACT评估指标有较好的相关性。     

阻塞性睡眠呼吸暂停低通气综合征呼出气冷凝液8-异前列烷的昼夜变化及其意义

目的 探讨阻塞性睡眠呼吸暂停低通气综合征(obstructive sleep apnea-hypopnea syndrome,OSAHS)患者呼出气冷凝液(exhaled breath condensate,EBC)8-异前列烷(8-isoprostane,8-isoPG)的昼夜变化及其意义.方法 采用德国JAEGER公司的呼出气收集器.收集40例OSAHS患者和30名正常对照者睡眠监测前后的EBC,同时采集睡眠监测后的血清,采用酶联免疫技术测定EBC及血清中8-isoPG的含量,并与睡眠监测指标进行相关性分析.结果 OSAHS组EBC中8-isoPG睡眠监测前为(13.08±1.42)ng/L、睡眠临测后为(14.93±1.39)ng/L(P<0.01).正常对照组EBC中8-isoPG睡眠监测前为(11.06±0.72)ng/L、睡眠监测后为(10.97±0.70)ng/L(P>0.05).OSAHS组睡眠监测后EBC及血清中8-isoPG比正常对照组升高,P<0.01.OSAHS患者睡眠监测后EBC 8-isoPG与血清8-isoPG呈正相关(r=0.685,P<0.01),与AHI呈正相关(r=0.650,P<0.05),与睡眠中最低血氧饱和度、基础血氧饱和度和平均血氧饱和度呈负相关(r=-0.406,-0.439,-0.454,P值均<0.05).结论 OSAHS患者存在夜间氧化应激反应增强,OSAHS患者早晨EBC中8-isoPG可以作为评价患者氧化应激状态和估计病情严重程度的较好指标.     

Cough,asthma, and cysteinyl-leukotrienes

Asthma is a chronic inflammatory disease of the lower airways, involving various cells such as eosinophils, and cytokines and mediators. Cyteinyl-leukotrienes (cys-LTs) are one of the chemical mediators that play major pathophysiological roles in asthma. They are produced by eosinophils and mast cells, and induce bronchoconstriction, mucous hypersecretion, microvascular leakage, eosinophil chemotaxis and airway remodeling. Anti-leukotrienes, including leukotriene receptor antagonists (LTRAs) which block cysLT1 receptors, exert both bronchodilatory and anti-inflammatory effects and are utilized as second- to third-line controller medication of persistent asthma.Cough is a major symptom of asthma, and cough variant asthma (CVA) is an asthma phenotype that solely presents with coughing. Sputum levels of cys-LTs are increased in patients with CVA. Antitussive effects of monotherapy with LTRAs in patients with CVA have been reported. We have recently demonstrated that 4 weeks' treatment with an LTRA montelukast exerted anti-inflammatory effect as proved by a decrease of sputum eosinophils, in addition to attenuation of cough VAS and capsaicin cough sensitivity, as reported previously. Spirometry, airway responsiveness, and impulse oscillation indices (respiratory resistance and reactance) were unchanged. These results suggested that the antitussive effect of montelukast in CVA might be attributable to its anti-inflammatory ability rather than bronchodilation. The treatment did not affect sputum levels of mediators (cys-LTs, LTB₄, PGD₂, PGE₂, PGF_2α, and TXB₂). Since inhaled corticosteroid does not seem to affect cough sensitivity while attenuating cough in patients with CVA, LTRAs may involve different mechanism(s) from that of corticosteroid.LTRAs must theoretically be effective against cough of asthmatic subjects through its “anti-asthma” effects, while evidence supporting direct antitussive effects of cys-LTs on “cough receptors” is scarce. An important clinical question is that whether LTRAs involve non-specific antitussive effects. While a definite answer is not available yet, this possibility seems unlikely at the moment, although some secondary anti-inflammatory properties have been reported for montelukast. This issue needs to be clarified by future research to avoid overuse of this expensive class of medication.     

Anaesthesia in aspirin-induced asthma

The triad of bronchial asthma, nasal polyposis, and intolerance to aspirin and aspirin-like chemicals are designated aspirin-induced asthma (AIA) or Samter's syndrome. The exact mechanism of the disease is unknown but it is thought to be a disorder of arachidonic acid metabolism. These patients are frequently referred to allergy clinics for preoperative evaluation for possible anesthetic agent sensitivity, requiring anesthesia for nasal polypectomy or several other reasons. Anesthetists must be aware of their pulmonary dysfunction, because the anesthetic management of asthma requires a specific approach. Marked cross-sensitivity with NSAIDs, which may also precipitate severe bronchospasm and adverse reactions, is the main problem faced by anesthetists in postoperative pain management. This article discusses the relationship between AIA and anesthesia. We also present our experience with 47 patients diagnosed with AIA between 1991 and 2003 in the department of chest diseases and adult allergy unit who underwent surgery requiring general anesthesia. In conclusion, preoperative evaluation of these patients and collaboration between the allergists and anesthesiologists is essential to prevent preoperative, perioperative and postoperative complications.     

慢性阻塞性肺疾病患者呼出气冷凝液中检测一氧化氮、8-异前列腺素的临床意义

目的观察慢性阻塞性肺疾病（COPD）患者呼出气冷凝液（EBC）中一氧化氮（NO）、8-异前列腺素（8-isoPG）的变化及其临床意义。方法收集COPD急性发作期（AECOPD）、缓解期患者和正常对照组的EBC,用硝酸还原法检测NO的浓度,酶免疫法检测8-isoPG的浓度。结果①AECOPD组（19例）患者EBC中NO和8-isoPG的浓度显著高于正常对照组（12例）,NO测定值分别为（80．83±40．15）μmol／L和（36．95±22．47）μmol／L,8-isoPG测定值分别为（13．56±11．11）ng／L和（5．87±3．39）ng／L,P〈0．05;②10例COPD急性发作期患者EBC中NO和8-isoPG的浓度显著高于缓解期,NO测定值分别为（91．09±34．30）μmol／L和（29．65±11．76）μmol／L,8-isoPG测定值分别为（17．60±12．44）ng／L和（5．23±6．20）ng／L,P〈0．05;③AECOPD组NO测定值与FEV1呈负相关（r=0．565,P〈0．05）,与血白细胞计数呈正相关（r=0．746,P〈0．01）。结论COPD患者急性发作期气道炎症反应和氧化应激增强。     

Increased plasma 8-isoprostane levels in hypertensive subjects: the Tsurugaya Project.

To examine the relationship between 8-isoprostane and blood pressure, we measured plasma 8-isoprostane concentration and home blood pressure levels in an elderly Japanese population. Our study population comprised 569 subjects aged 70 years and over who were not receiving antihypertensive medication. On the basis of their blood pressure values, the participants were classified into three groups: normotensive (home blood pressure <135/85 mmHg), hypertensive (home blood pressure 135/85-160/90 mmHg), and severely hypertensive (home blood pressure > or =160/90 mmHg). The mean plasma 8-isoprostane level in the severely hypertensive group (21.1+/-5.2 pg/ml) was significantly higher than that in the normotensive (20.2+/-4.9 pg/ml) or hypertensive (19.7+/-5.1 pg/ml) group, and this result was unchanged when we adjusted for possible confounding factors such as age, sex, use of vitamin A, C or E supplements, smoking status, drinking status, body mass index, use of non-steroidal anti-inflammatory drugs, history of diabetes, hypercholesterolemia, home heart rate and serum creatinine level. Thus, the level of plasma 8-isoprostane appears to be elevated in older subjects with severe hypertension.     

Increased 8-isoprostane and interleukin-6 in breath condensate of obstructive sleep apnea patients

STUDY OBJECTIVES: Obstructive sleep apnea (OSA) is characterized by repeated episodes of upper airways obstruction during sleep that result in episodes of hypoxia. An increase of systemic biomarkers of inflammation and oxidative stress has been found in patients with OSA and obesity. DESIGN: The aim of this study was to measure the levels of markers of inflammation (interleukin [IL]-6) and oxidative stress (8-isoprostane) in the exhaled breath condensate of OSA and obese patients. PATIENTS AND METHODS: Eighteen OSA patients (13 men; mean [+/- SEM] age, 44 +/- 7 years), 10 obese subjects (4 men; mean age, 39 +/- 8 years), and 15 healthy age-matched subjects (8 men; mean age, 42 +/- 4 years) were recruited. IL-6 and 8-isoprostane were measured in exhaled breath condensate by a specific enzyme immunoassay kit. Measurements and results: Higher concentrations of IL-6 were found in OSA patients (8.7 +/- 0.3 pg/mL) than in healthy control subjects (1.6 +/- 0.1 pg/mL; p < 0.0001). Obese subjects also had higher levels than healthy control subjects, but lower levels than OSA patients (2.1 +/- 0.2 pg/mL, p < 0.05 and p < 0.0001 respectively). Furthermore, 8-isoprostane levels were found to be higher in OSA patients (7.4 +/- 0.7 pg/mL) than in obese subjects (5 +/- 0.3 pg/mL; p = 0.4) and healthy subjects (4.5 +/- 0.5 pg/mL; p < 0.005). We found a positive correlation between these two markers and neck circumference and apnea/hypopnea index. CONCLUSIONS: These findings suggest that inflammation and oxidative stress are characteristic in the airways of OSA patients but not in obese subjects, and that their levels depend on the severity of the OSA. The measurement of IL-6 and 8-isoprostane levels may prove to be useful in screening and monitoring obese patients who have a high risk of developing OSA.     

Increased exhaled nitric oxide in chronic bronchitis: comparison with asthma and COPD

STUDY OBJECTIVES: To test the hypothesis that exhaled nitric oxide (NO) is increased in patients with chronic bronchitis, and to compare the results with exhaled NO in patients with asthma and COPD. STUDY DESIGN: Cross-sectional survey. SETTING AND PATIENTS: Veterans Administration pulmonary function laboratory. Patients (n = 179) were recruited from 234 consecutive patients. Two nonsmoking control groups of similar age, with normal spirometry measurements and no lung disease, were used (18 patient control subjects and 20 volunteers). MEASUREMENTS: Participants completed questionnaires and spirometry testing. Exhaled NO was measured by chemiluminescence using a single-breath exhalation technique. RESULTS: Current smoking status was associated with reduced levels of exhaled NO (smokers, 9. 2 +/- 0.9 parts per billion [ppb]; never and ex-smokers, 14.3 +/- 0. 6 ppb; p < 0.0001). Current smokers (n = 57) were excluded from further analysis. Among nonsmokers, the levels of exhaled NO were significantly higher in patients with chronic bronchitis (17.0 +/- 1. 1 ppb; p = 0.035) and asthma (16.4 +/- 1.3 ppb; p = 0.05) but not in those with COPD (14.7 +/- 1.0 ppb; p = 0.17) when compared with either control group (patient control subjects, 11.1 +/- 1.6 ppb; outside control subjects, 11.5 +/- 1.5 ppb). The highest mean exhaled NO concentration occurred in patients with both chronic bronchitis and asthma (20.2 +/- 1.6 ppb; p = 0.005 vs control subjects). CONCLUSIONS: Exhaled NO is increased in patients with chronic bronchitis. The increase of exhaled NO in patients with chronic bronchitis was similar to that seen in patients with asthma. The highest mean exhaled NO occurred in patients with both chronic bronchitis and asthma. Exhaled NO was not increased in patients with COPD. Although chronic bronchitis and asthma have distinct histopathologic features, increased exhaled NO in patients with both diseases suggests common features of inflammation.     

阻塞性睡眠呼吸暂停低通气综合征患者治疗前后呼出气冷凝液中8-异前列腺素水平的变化

目的探讨阻塞性睡眠呼吸暂停低通气综合征（OSAHS）患者治疗前后氧化应激标记物的变化以及这些变化与病情严重程度的关系。方法68例OSAHS患者中40例接受治疗2个月,其中33例使用持续气道正压通气治疗（CPAP）、5例行外科手术、2例使用口矫器,28例未经任何治疗,随访2个月。所有患者分别于治疗前和治疗后2个月,于晨起空腹时收集呼出气冷凝液（EBC）,同时抽取静脉血5ml,应用酶联免疫吸附法（ELISA）测定EBC和血清中8．异前列腺素的含量,并进行统计学的处理。结果治疗后EBC和血清中8-异前列腺素的水平较治疗前明显降低,差异具有显著性[EBC：（19．9±2．9）pg／ml,（14．4±3．1）pg/ml,P〈0．001;血清：（29．9±5．7）pg／ml,（20．4±3．9）pg／ml,P〈0．001];EBC和血清中8-异前列腺素水平的绝对变化（治疗后．治疗前）与呼吸暂停低通气指数（AHI）和最长窒息时间的绝对变化呈正相关（EBC：r=0．69,r=0．50,P〈0．001;血清：r=0．72,r=0．46,P〈0．001）,与夜间最低SaO2的绝对变化呈负相关（EBC：r=-0．58,P〈0．001;血清：r=-0．53,P〈0．001）。结论EBC和血清中8-异前列腺素的水平能通过治疗有效降低,治疗前后的水平变化与病情的严重程度有关,可作为随访病情和反映治疗效果的指标。