Airway responses to antigen challenge in allergic rhinitis and allergic asthma

The density dependence of the maximum expiratory flow-volume curve, functional residual capacity (FRC), and specific airway conductance (SGaw) were determined before and during bronchial provocation with ragweed extract in 27 subjects with ragweed hypersensitivity and a history of either bronchial asthma (16 subjects) or allergic rhinitis (11 subjects). Mean baseline SGaw was significantly lower while mean volume of isoflow (Visov) and FrC were significantly higher in subjects with bronchial asthma. During antigen challenge, 10 of 16 subjects with bronchial asthma (63%) and five of 11 subjects with allergic rhinitis (45%) showed a greater than 35% decrease in SGaw ("reactors"): mean relative decreases in SGaw from baseline were 46% and 53%, respectively. The remaining subjects showed a less than 35% decrease in SGaw ("nonreactors") with mean relative decreases of 9% (allergic asthma) and 6% (allergic rhinitis). Mean Visov increased in all subjects with bronchial asthma and in eight of 11 subjects with allergic rhinitis. A significant increase in FRC (6%) was seen only in the "reactors" with bronchial asthma. Following antigen challenge, the beta adrenergic agonist, isoetharine, increased SGaw and decreased Visov. We conclude that in asymptomatic subjects with ragweed hypersensitivity, (1) central and peripheral airway function is more abnormal in subjects with bronchial asthma than in subjects with allergic rhinitis, (2) subjects of both groups show quantitatively and qualitatively comparable airway responses during antigen challenge with a decrease in SGaw or an increase in Visov, possibly representing increase in central and/or peripheral airflow resistance, respectively, (3) Visov may be a more sensitive indicator of airway response to antigen challenge than SGaw, and (4) the bronchodilator effects of a beta adrenergic agonist on antigen-induced bronchospasm are similar in both groups.     

Does Low FEV1 in Addition to Fixed Ratio and/or Lower Limit of Normal of FEV1/FVC Improve Prediction of Mortality in COPD? The NHANES-III-linked-mortality Cohort

Purpose

There is presently an ongoing debate on the relative merits of suggested criteria for spirometric airway obstruction. This study tests the null hypothesis that no superiority exists with the use of fixed ratio (FR) of forced expiratory volume in the first second (FEV1)/forced vital capacity (FVC) < 0.7 versus less than lower limit predicted (LLN) criteria with or without FEV1 <80% predicted in regards to future mortality.

A placebo-controlled trial of procaterol: A new long-acting oral beta2-agonist in bronchial asthma

Procaterol hydrochloride, a potent beta 2-adrenergic bronchodilator developed in Japan, was evaluated in a double-blind, placebo-controlled study for efficacy and safety in 45 patients (ages 18 to 55 yr) with chronic documented reversible airway disease. After a 1-week placebo washout period, patients were administered either 0.05 mg or 0.10 mg of procaterol or placebo twice daily for 2 wk. Spirometric determinations, vital signs, and ECGs were obtained at 1/2, 1, 2, 4, 6, and 8 hr after the first dose and at the same time intervals after 1 and 2 wk of treatment. Patients recorded on a daily basis peak flow rates, asthma symptoms, need for supplemental aerosol, concurrent medications, and side effects. Spirometry results indicated significant improvement in pulmonary function with both doses of procaterol compared with placebo (P less than 0.05). The larger dose was generally more effective. Bronchodilatation was evident 1/2 hr after dosing and peaked at 2 hr. At 8 hr after 0.10 mg of procaterol, FEV1 was still above predose values. Daily peak flow rates were significantly higher with 0.10 mg than with 0.05 mg (P less than 0.05) and placebo (P less than 0.001). Tremor and nervousness were the most frequent side effects. They occurred in a dose-related frequency, were mild and transient, and occurred early in treatment. No significant drug-related changes were noted in ECGs, heart rate, blood pressure, or clinical laboratory data. Procaterol was found to be an effective, well-tolerated oral bronchodilator with a long duration of action, especially at 0.10 mg twice daily.     

清咳平喘颗粒治疗痰热郁肺型咳嗽的临床疗效观察

目的 观察清咳平喘颗粒治疗痰热郁肺型咳嗽的临床有效性。方法 选取2020年1月—2021年6月上海中医药大学附属龙华医院呼吸科门诊就诊的痰热郁肺型咳嗽患者100例,按随机数字表法分为对照组和治疗组各50例,对照组为西医常规治疗,治疗组在西医常规治疗基础上联合清咳平喘颗粒治疗。两组均连续治疗2周。观察两组患者治疗前后的中医证候、咳嗽症状、气道反应（血清免疫球蛋白E、外周血嗜酸性粒细胞）、肺功能［最大呼气流量、第1秒用力呼气容积（forced expiratory volume for 1 second,FEV1）与用力肺活量（forced vital capacity,FVC）的比值］、生活质量及不良反应情况。结果 治疗后,对照组和治疗组的总有效率分别是90%、94%,两组比较差异无统计学意义（P>0.05）。治疗后,两组患者中医证候评分、日间及夜间咳嗽积分较治疗前降低,且治疗组明显低于对照组（P<0.05）。治疗后,两组血清免疫球蛋白E、外周血嗜酸性粒细胞较治疗前明显下降,且治疗组气道反应指标改善好于对照组（P<0.05）。治疗后,两组最大呼气流量、FEV1/FVC较治疗前明显上升（P<0.05）,但两组比较差异无统计学意义（P>0.05）。随访时两组患者的生活质量评分较治疗前均显著升高,治疗组评分改善优于对照组,两组比较差异具有统计学意义（P<0.05）。治疗期间两组均未发生不良反应。结论 清咳平喘颗粒在治疗痰热郁肺型咳嗽安全性良好,有助于改善咳嗽症状,改善肺通气,提高患者生活质量。     

Evaluating the Health Risk from Secondary Sulfates in Eastern North American Regional Ambient Air Particulate Matter

Epidemiological studies of particulate matter (PM) using central area monitors have associated total PM mass, as well as certain individual components of PM, including sulfate, with adverse human health effects. However, some recent studies that used concentrated ambient particles (CAPs) or analyzed the effects of air pollution from different sources or geographic areas suggest that while some particles may be harmful, other particulate species including secondary sulfates may have negligible health effects. Toxicology studies to date also suggest that secondary sulfates pose little health risk. While studies using central-area monitors implicitly assume that all residents of the area are exposed to the same levels of pollution, newer studies find substantial health effects for those in close proximity to major roads. These latter studies recognize that although population exposure to widespread pollutants, such as total PM mass and sulfates, may be relatively uniform over a wide area, exposure to pollutants from local sources is not. While there is an emerging literature associating several adverse health effects with proximity to local pollution sources, the current database provides limited information that allows identification of specific particulate species that may cause little to no harm. In this article, we suggest that ambient secondary sulfates, and eastern North American regional air masses generally, appear to have little adverse impact on public health. This suggestion is based on evidence gleaned from eight avenues of investigation: (1) recent non-central-area monitor studies, including exposure gradient or proximity studies; (2) CAPs studies; (3) studies that examine effects related to different geographic areas or sources; (4) toxicology studies; (5) the limited number of studies that analyze existing central-area monitor data to explicitly examine the health impacts of sulfate and acidity versus PM mass; (6) “modern” area monitor studies with additional capabilities to distinguish among sources of pollution; (7) partial reinterpretation of two pivotal cohort studies; and (8) studies separating effects of secondary sulfates from those of primary metal sulfates. However, uncertainties remain regarding the role that secondary sulfates may play in ambient PM chemistry pathways leading to potentially harmful products, such as the possible effects of secondary organic aerosols that may be the product of acid catalysis of sulfur dioxide. Thus, more targeted study is needed, and some research suggestions are made in this regard.     

呼出一氧化氮预测放射性肺炎价值的临床研究

目的 探讨一氧化氮呼出值（FeNO）预测放射性肺炎的价值。方法 收集2016年8月至2017年2月收治的131例胸部肿瘤患者，对放疗前、后的FeNO水平进行检测，并分析大气道（50 ml／s流速）、小气道（200 ml／s流速）和肺泡放疗前、后FeNO水平与放射性肺炎分级的关系。结果 131例患者放疗前平均大气道FeNO为19.86 ppb，小气道为9.49 ppb，肺泡为2.84 ppb；仅肺泡FeNO放疗后上升明显，差异有统计学意义（P=0.015）。全组患者放疗后出现1级放射性肺炎43例，2级70例，3级18例，无4级及以上者。放疗前、后大气道、小气道、肺泡FeNO水平与放射性肺炎分级无关。结论 肺泡FeNO在放疗后上升明显，但大、小气道放疗前、后FeNO水平不能预测放射性肺炎。     

Social support as a predictor exhaled nitric oxide in healthy individuals across time

Psychosocial factors such as social support and depression have long been associated with health outcomes. Elevated depressive symptoms are usually associated with worse health outcomes, whereas social support has been related to improvements in health. Nitric oxide levels are an important marker of both cardiovascular health and immune function. Research suggests that exhaled nitric oxide is affected by stress, negative affect, and depression; however, the effect of social support has not been previously explored. Thus, we sought to examine the association of social support, negative affect, and depression with exhaled nitric oxide in a group of 35 healthy individuals (10 males and 25 females) with a mean age of 20.5 years across five weekly assessments. Results showed that changes in social support within individuals were positively associated with levels of exhaled nitric oxide independent of other psychosocial factors. Further exploration of the health implications of this positive relationship between airway nitric oxide and social support is necessary.     

FEV1/FEV6 is effective as a surrogate for FEV1/FVC in the diagnosis of chronic obstructive pulmonary disease

Background and objectiveChronic Obstructive Pulmonary Disease (COPD) causes substantial morbidity and mortality across the globe. Diagnosis of COPD requires post-bronchodilator FEV1/FVC <0.70 as per GOLD Guidelines. FVC maneuver requires a minimum of 6 seconds of forceful expiration with no flow for 1 second for an accepted effort, which lacks any fixed cut-off point. This leads to discomfort, especially in advanced COPD and old aged population. We conducted this study to find the utility of FEV1/FEV6 as a surrogate for FEV1/FVC, the correlation between the two ratios, and the fixed cut-off value of FEV1/FEV6 for COPD diagnosis.MethodsThis was a prospective, cross-sectional study approved by the institutional ethics committee conducted from January 2017 to November 2018. Consented patients above 18 years suspected of COPD underwent Spirometry as per ATS guidelines. FEV1, FEV6, FEV1/FEV6 and FEV1/FVC ratios were recorded from the best acceptable maneuver.ResultsOut of 560 screened patients, 122 diagnosed as COPD. The correlation coefficient between the post-bronchodilator FEV1/FVC ratio and FEV1/FEV6 ratio was 0.972 (p < 0.01). The relationship between the post-bronchodilator FEV1/FVC ratio and FEV1/FEV6 ratio (linear regression analysis) was found out as: FEV1/FVC = ?1.845 + 1.009(FEV1/FEV6). Using this formula, the post-bronchodilator FEV1/FEV6 value of 71.845 was obtained corresponding to the post-bronchodilator FEV1/FVC value of 70.00.ConclusionWe found a positive correlation coefficient (r = 0.972, p < 0.001) between the FEV1/FEV6 and FEV1/FVC ratios and the cut off value of 71.845 (p < 0.01) for the post-bronchodilator FEV1/FEV6 ratio for the diagnosis of COPD. Thus FEV1/FEV6 should be used as a surrogate for FEV1/FVC for the diagnosis of COPD.