Prediction and types of dead-space fraction during exercise in male chronic obstructive pulmonary disease patients

A high dead space (V_D) to tidal volume (V_T) ratio during peak exercise (V_D/V_Tpeak) is a sensitive and consistent marker of gas exchange abnormalities; therefore, it is important in patients with chronic obstructive pulmonary disease (COPD). However, it is necessary to use invasive methods to obtain V_D/V_Tpeak, as noninvasive methods, such as end-tidal PCO₂ (P_ETCO_2peak) and P_ETCO₂ adjusted with Jones’ equation (P_JCO_2peak) at peak exercise, have been reported to be inconsistent with arterial PCO₂ at peak exercise (P_aCO_2peak). Hence, this study aimed to generate prediction equations for V_D/V_Tpeak using statistical techniques, and to use P_ETCO_2peak and P_JCO_2peak to calculate the corresponding V_D/V_Tpeaks (i.e., V_D/V_TpeakETV_D/V_TpeakJ).A total of 46 male subjects diagnosed with COPD who underwent incremental cardiopulmonary exercise tests with P_aCO₂ measured via arterial catheterization were enrolled. Demographic data, blood laboratory tests, functional daily activities, chest radiography, two-dimensional echocardiography, and lung function tests were assessed.In multivariate analysis, diffusing capacity, vital capacity, mean inspiratory tidal flow, heart rate, and oxygen pulse at peak exercise were selected with a predictive power of 0.74. There were no significant differences in the PCO_2peak values and the corresponding V_D/V_Tpeak values across the three types (both p = NS).In subjects with COPD, V_D/V_Tpeak can be estimated using statistical methods and the P_ETCO_2peak and P_JCO_2peak. These methods may have similar predictive power and thus can be used in clinical practice.     

钾离子浓度对离体毛细胞凋亡的影响

目的 探讨钾离子浓度对离体毛细胞凋亡的作用.方法 采用胶原酶制备离体耳蜗毛细胞,模拟病理状态下的钾离子浓度(100mmol/L)环境,用倒置显微镜、荧光显微镜下观察毛细胞凋亡改变.结果 病理状态钾环境下离体耳蜗毛细胞的凋亡改变类似于Hank′s液下毛细胞的凋亡改变,即胞核皱缩;纤毛泡状或倒伏;胞质内可见布朗运动.荧光显微镜下凋亡毛细胞呈红色或红黄色荧光,毛细胞形态完整,无胞膜破裂或胞质溢出.随着时间延长毛细胞凋亡数逐步增多,二者凋亡率差异无统计学意义(P＞0.05).结论 在离体环境下,此种病理状态下的钾离子浓度(100mmol/L)对离体毛细胞的凋亡无显著性影响.     

Exposure to ambient air pollution and the incidence of lung cancer and breast cancer in the Ontario Population Health and Environment Cohort

Lung and female breast cancers are highly prevalent worldwide. Although the association between exposure to ambient fine particulate matter (PM_2.5) and lung cancer has been recognized, there is less evidence for associations with other common air pollutants such as nitrogen dioxide (NO₂) and ozone (O₃). Even less is known about potential associations between these pollutants and breast cancer. We conducted a population-based cohort study to investigate the associations of chronic exposure to PM_2.5, NO₂, O₃ and redox-weighted average of NO₂ and O₃ (O_x) with incident lung and breast cancer, using the Ontario Population Health and Environment Cohort (ONPHEC), which includes all long-term residents aged 35–85 years who lived in Ontario, Canada, 2001–2015. Incident lung and breast cancers were ascertained using the Ontario Cancer Registry. Annual estimates of exposures were assigned to the residential postal codes of subjects for each year during follow-up. We used Cox proportional-hazards models adjusting for personal- and neighborhood-level covariates. Our cohorts for lung and breast cancer analyses included ~4.9 million individuals and ~2.5 million women, respectively. During follow-up, 100,146 incident cases of lung cancer and 91,146 incident cases of breast cancer were diagnosed. The fully adjusted analyses showed positive associations of lung cancer incidence with PM_2.5 (hazard ratio [HR] = 1.02 [95% CI: 1.01–1.05] per 5.3 μg/m³) and NO₂ (HR = 1.05 [95% CI: 1.03–1.07] per 14 ppb). No associations with lung cancer were observed for O₃ or O_x. Relationships between PM_2.5 and NO₂ with lung cancer exhibited a sublinear shape. We did not find compelling evidence linking air pollution to breast cancer.     

发泡胶在鼻咽癌放疗中对剂量分布的影响

目的：研究在鼻咽癌放射治疗中应用发泡胶进行体位固定对剂量分布的影响。方法：随机选取11例应用头颈肩热塑膜联合发泡胶进行体位固定的鼻咽癌患者,在Pinnacle计划系统中将空白CT值设置到发泡胶的CT值以下,以确保发泡胶的CT值被计算在内,作为第一组计划（Plan_F）。同时,复制第一组计划并在定位图像上勾画出发泡胶,设置发泡胶的CT值为0,在不改变射野分布、权重及计划跳数的情况下重新计算剂量分布,作为第二组计划（Plan_N）。比较两组计划的靶区及周围正常组织的剂量分布。结果：对于靶区（GTVnx、GTVnd、GTVrpn、PGTVnx、CTV1、PTV1、CTV2、PTV2）的最小剂量Dmin,最大剂量Dmax,平均剂量Dmean去除发泡胶之后,所测 255组数据中仅有6组数据出现减小（约占2.4%）,Dmin、Dmax和Dmean的变化度（%）（X±SD）依次为0.215±0.969、 0.395±0.623和 0.442±0.178,其中除了GTVrpn的Dmin（P=0.727）和Dmax（P=0.142）,PGTVnx的Dmin（P=0.623）,CTV1 Dmin（P=0.713）,CTV2 Dmax（P=0.066）,其他评估指标皆显示发泡胶使用组剂量低于去除发泡胶组（P＜0.05）;而对于周围正常组织（脑干、脊髓、左右晶体、左右视神经和腮腺）的Dmean和Dmax去除发泡胶之后,所测的154组数据中仅有14组数据出现减小（约占9.1%）,Dmax和Dmean的变化度（%）（X±SD）依次为0.194±0.192 和0.129±0.128,其中除了左、右晶体的平均剂量Dmean（P值分别为0.123和0.06）,其余各项指标同样显示发泡胶使用组剂量低于去除发泡胶组（P＜0.05）。结论：发泡胶的使用降低了实际治疗过程中受照部位的剂量,但发泡胶对剂量变化的影响都在目前临床可接受的范围之内。     

From the Cover: Association of improved air quality with lower dementia risk in older women

Late-life ambient air pollution is a risk factor for brain aging, but it remains unknown if improved air quality (AQ) lowers dementia risk. We studied a geographically diverse cohort of older women dementia free at baseline in 2008 to 2012 (n = 2,239, aged 74 to 92). Incident dementia was centrally adjudicated annually. Yearly mean concentrations of fine particulate matter (PM_2.5) and nitrogen dioxide (NO₂) were estimated using regionalized national universal kriging models and averaged over the 3-y period before baseline (recent exposure) and 10 y earlier (remote exposure). Reduction from remote to recent exposures was used as the indicator of improved AQ. Cox proportional hazard ratios (HRs) for dementia risk associated with AQ measures were estimated, adjusting for sociodemographic, lifestyle, and clinical characteristics. We identified 398 dementia cases during follow up (median = 6.1 y). PM_2.5 and NO₂ reduced significantly over the 10 y before baseline. Larger AQ improvement was associated with reduced dementia risks (HR_PM2.5 0.80 per 1.78 μg/m³, 95% CI 0.71–0.91; HR_NO2 0.80 per 3.91 parts per billion, 95% CI 0.71–0.90), equivalent to the lower risk observed in women 2.4 y younger at baseline. Higher PM_2.5 at baseline was associated with higher dementia risk (HR_PM2.5 1.16 per 2.90 μg/m³, 95% CI 0.98–1.38), but the lower dementia risk associated with improved AQ remained after further adjusting for recent exposure. The observed associations did not substantially differ by age, education, geographic region, Apolipoprotein E e4 genotypes, or cardiovascular risk factors. Long-term AQ improvement in late life was associated with lower dementia risk in older women.

Consistent evidence from epidemiologic studies and toxicological experiments has shown that ambient air pollution is an important modifiable risk factor of dementia (1). Several studies have shown an increased risk of dementia associated with late-life exposures to regional fine particulate matter (PM_2.5; with aerodynamic diameter < 2.5 μm) (2–15) and gaseous pollutants (e.g., NO₂; NO_x) (2–4, 11, 12, 15–17) in particular. Over the past 50 y, significant improvements in air quality (AQ) have been observed across the United States because of national policies and strategies aimed at regulating pollution from stationary (power plants; factories) and mobile (vehicles) sources (18). Several US studies have shown that these long-term reductions in air pollution levels are associated with improved lung function (19), decreased bronchitic symptoms (20), lower asthma incidence (21), lengthened life expectancy (22), and reduced mortality (23). However, it remains unclear whether improved AQ also benefits the aging brains.Therefore, we conducted a multiyear study to examine the association between improved AQ and incidence of dementia, which was based on Diagnostic and Statistical Manual of Mental Disorders (Fourth edition) criteria and centrally adjudicated annually (24, 25). We examined data from the Women’s Health Initiative (WHI) Memory Study (WHIMS)—Epidemiology of Cognitive Health Outcomes (WHIMS-ECHO) that included a combined 20 y of data on individual-level outdoor air pollution (1998 to 2012) estimated using regionalized national universal kriging models (26–28) and cognitive function assessed annually (2008 to 2018) in a geographically diverse sample of community-dwelling older women in the United States. We hypothesized that improved AQ over the span of 10 y, as indicated by reductions in PM_2.5 and NO₂ (proxy for traffic pollutants), was associated with lower dementia risk.     

空军部队军人焦虑特点及影响因素研究

目的:探讨空军军人焦虑的特点及其影响因素.方法:采用状态-特质焦虑问卷(STAI),症状自评量表(SCL-90),艾森克个性问卷(EPQ)和简易应对方式问卷对空军1696名军人进行团体测试,将焦虑得分与一般人群的比较;以性别、年龄和工种进行分组,采用t检验或单因素方差分析进行组间比较;进行焦虑与心理健康、个性和应对方式的逐步回归分析.结果:①空军男性和女性军人的状态焦虑和特质焦虑得分均高于一般人群(P＜0.01);②空军军人焦虑的发展特点:女性焦虑总分、状态焦虑和特质焦虑得分显著高于男性(P＜0.01);焦虑总分、状态焦虑和特质焦虑得分均存在年龄差异(P＜0.05),其中,"＜20岁"组与"20～24岁"组间焦虑总分、状态焦虑得分存在显著差异(P＜0.05);特质焦虑得分在"＜20岁"组与"≥25岁"组间存在显著差异(P＜0.05);不同工种之间,只有焦虑总分具有统计学差异(P＜0.05); ③逐步回归分析提示,积极应对得分和SCL-90总均分对军人的焦虑水平有直接效应,而EPQ的N,E,P和消极应对得分对军人的焦虑水平具有间接效应.结论:空军军人的焦虑水平显著高于一般人群,且具有性别、年龄和工种特征;空军军人的焦虑与心理健康水平、应对方式和个性有关.     

The efficacy of endobronchial valves for the treatment of bronchopleural fistula: a single-arm clinical trial

BackgroundA bronchopleural fistula (BPF) is defined as communication between the bronchus and pleural cavity, and it is a dreaded complication of severe pulmonary disease. Surgical intervention, pleurodesis, and prolonged chest tube drainage have several disadvantages. To overcome these, many attempts have been made to treat BPF with bronchoscopy, especially with the insertion of an endobronchial one-way valve (EBV). Endobronchial valves for the treatment of BPF which had less trauma, relatively short operation time, better safety, and patients are more likely to accept this operation. If there is a definite efficacy, it should be widely used in later clinical practice. This study aimed to confirm the efficacy of endobronchial valves for the treatment of BPF.MethodsWe retrospectively reviewed data from 26 patients who were treated for BPF using an EBV between August 2017 and October 2020. This sample constitutes all patients treated in our hospital (Shanghai Pulmonary Hospital, Tongji University School of Medicine) for this condition and with this intervention during this timeframe. We collected general information about the patient, complications of the procedure, and chest tube indwelling to assess the efficacy and safety of the procedure.ResultsA total of 26 patients underwent EBV placement procedures; left upper lobe (LUL) was the most common lobe in which the valves were placed. The underlying etiologies for BPF were postoperative BPF (50%; n=14), pneumothorax (15%; n=4), non-tuberculosis mycobacteria (NTM) (19%; n=5), and tuberculosis (12%; n=3). Eleven patients underwent chest tube insertion. The average chest tube duration in the group of patients before receiving valves was 66 days (median, 65 days; range, 14–187 days). The average duration after which the chest tube was removed was 17.5 days after EBV placement (median, 7 days; range, 2–90 days). The effective rate of EBV for the treatment of BPF was 73.1%. Patients for whom the valves were not removed, there were no valve related complications.ConclusionsEBV placement is a relatively mature procedure, which is safe and effective, and generates less trauma and fewer complications. And this intervention may be suitable for wide application in clinical practice.     

甲醇-二硫化碳解吸-气相色谱法测定工作场所空气中1,2-二氯乙烯

目的 建立甲醇-二硫化碳解吸-气相色谱法测定工作场所空气中1,2-二氯乙烯的方法.方法 空气中1,2-二氯乙烯用活性炭管采集,经甲醇-二硫化碳溶剂解吸,DB-FFAP毛细管色谱柱(30mx0.25mm,0.25 μm)分离,火焰离子化检测器检测,保留时间定性,峰高或峰面积定量.结果 顺-1,2-二氯乙烯、反-1,2-二...