Resveratrol relieves particulate matter (mean diameter < 2.5 μm)‐induced oxidative injury of lung cells through attenuation of autophagy deregulation

Oxidative stress and inflammation are critically implicated in ambient fine particulate matter (mean diameter < 2.5 μm; PM_2.5)‐induced lung injury. Autophagy, playing a crucial role in various physiopathological conditions, modulates cellular homeostasis and stress adaptation. Resveratrol is a phytoalexin that exerts potent antioxidant effects on cardiopulmonary diseases. To date, the mechanisms by which resveratrol protects against PM_2.5 remain to be elucidated. In the present study, we investigated the effect of resveratrol on PM_2.5‐induced oxidative injury. The potential role of nuclear factor erythroid‐2‐related factor 2 and autophagy in this progress was explored. Human bronchial epithelial cells were treated with PM_2.5 and the cytotoxicity and oxidative stress markers were determined. The results showed that PM_2.5 decreased cell viability and elevated the level of lactate dehydrogenase. The levels of malondialdehyde and reactive oxygen species were increased by PM_2.5 exposure. PM_2.5 also induced a significant increase of the inflammatory cytokines including interleukin (IL)‐6, IL‐8, IL‐1β and tumor necrosis factor α. Meanwhile, PM_2.5 triggered autophagy formation and alteration of the nuclear factor erythroid‐2‐related factor 2 pathway. Furthermore, human bronchial epithelial cells were co‐treated with PM_2.5 and resveratrol in the presence or absence of 3‐methylamphetamine, an inhibitor of autophagic formation. It was revealed that resveratrol intervention abolished PM_2.5‐induced oxidative injury partially through the suppression of autophagy deregulation. Findings from this study could provide new insights into the molecular mechanisms of pulmonary intervention during PM_2.5 exposure.     

Ultrafine particulate matter exposure impairs vasorelaxant response in superoxide dismutase 2-deficient murine aortic rings

Studies have linked exposure to ultrafine particulate matter (PM) and adverse cardiovascular events. PM-induced oxidative stress is believed to be a key mechanism underlying observed adverse vascular effects. Advanced age is one factor known to decrease antioxidant defenses and confer susceptibility to the detrimental vascular effects seen following PM exposure. The present study was designed to investigate the vasomotor responses following ultrafine PM exposure in wild type (WT) and superoxide dismutase 2-deficient (SOD2^+/–) mice that possess decreased antioxidant defense. Thoracic aortic rings isolated from young and aged WT and SOD2^+/– mice were exposed to ultrafine PM in a tissue bath system. Aortic rings were then constricted with increasing concentrations of phenylephrine, followed by relaxation with rising amounts of nitroglycerin (NTG). Data demonstrated that ultrafine PM decreased the relaxation response in both young WT and young SOD2^+/– mouse aortas, and relaxation was significantly reduced in young SOD2^+/– compared to WT mice. Ultrafine PM significantly diminished the NTG-induced relaxation response in aged compared to young mouse aortas. After ultrafine PM exposure, the relaxation response did not differ markedly between aged WT and aged SOD2^+/– mice. Data demonstrated that the greater vascular effect in aortic rings in aged mice ex vivo after ultrafine PM exposure may be attributed to ultrafine PM-induced oxidative stress and loss of antioxidant defenses in aged vascular tissue. Consistent with this conclusion is the attenuation of NTG-induced relaxation response in young SOD2^+/– mice.

Abbreviations: H₂O₂: hydrogen peroxide; NTG: nitroglycerin; PAH: polycyclic aromatic hydrocarbons; PE: l-phenylephrine; PM: particulate matter; ROS: reactive oxygen species; SOD2: superoxide dismutase 2 deficient; WT: wild type     

Time course of systemic oxidative stress and inflammatory response induced by an acute exposure to Residual Oil Fly Ash

It is suggested that systemic oxidative stress and inflammation play a central role in the onset and progression of cardiovascular diseases associated with the exposure to particulate matter (PM). The aim of this work was to evaluate the time changes of systemic markers of oxidative stress and inflammation, after an acute exposure to Residual Oil Fly Ash (ROFA). Female Swiss mice were intranasally instilled with a ROFA suspension (1.0 mg/kg body weight) or saline solution, and plasma levels of oxidative damage markers [thiobarbituric acid reactive substances (TBARSs) and protein carbonyls], antioxidant status [reduced (GSH) and oxidized (GSSG) glutathione, ascorbic acid levels, and superoxide dismutase (SOD) activity], cytokines levels, and intravascular leukocyte activation were evaluated after 1, 3 or 5 h of exposure. Oxidative damage to lipids and decreased GSH/GSSG ratio were observed in ROFA-exposed mice as early as 1 h. Afterwards, increased protein oxidation, decreased ascorbic acid content and SOD activity were found in this group at 3 h. The onset of an adaptive response was observed at 5 h after the ROFA exposure, as indicated by decreased TBARS plasma content and increased SOD activity. The observed increase in oxidative damage to plasma macromolecules, together with systemic antioxidants depletion, may be a consequence of a systemic inflammatory response triggered by the ROFA exposure, since increased TNF-α and IL-6 plasma levels and polymorphonuclear leukocytes activation was found at every evaluated time point. These findings contribute to the understanding of the increase in cardiovascular morbidity and mortality, in association with environmental PM inhalation.     

Preoperative evaluation and indications for pulmonary metastasectomy

Pulmonary metastasectomy (PM) is an established treatment that can provide improved long-term survival for patients with metastatic tumor(s) in the lung. In the current era, where treatment options other than PM such as stereotactic body radiation therapy (SBRT), immunotherapy, and molecular-targeted therapy are available, thoracic surgeons should review the approach to the preoperative evaluation and the indications. Preoperative evaluation consists of history and physical examinations, physiological tests, and radiological examinations. Radiological examinations serve to identify the differential diagnosis of the pulmonary nodules, evaluate their precise number, location, and features, and search for extra thoracic metastases. The indication of PM should be considered from both physiological and oncological points of view. The general criteria for PM are as follows; (I) the patient has a good general condition, (II) the primary malignancy is controlled, (III) there is no other extrapulmonary metastases, and (IV) the pulmonary lesion(s) are thought to be completely resectable. In addition to the general eligibility criteria of PM, prognostic factors of each tumor type should be considered when deciding the indication for PM. When patients have multiple poor prognostic factors and/or a short disease-free interval (DFI), thoracic surgeons should not hesitate to observe the patient for a certain period before deciding on the indication for PM. A multidisciplinary discussion is needed in order to decide the indication for PM.     

Indoor particle counts during Asian dust events under everyday conditions at an apartment in Japan

Objective

Asian dust storms originating from arid regions of Mongolia and China are a well-known springtime phenomenon throughout East Asia. Evidence is increasing for the adverse health effects caused by airborne desert dust inhalation. Given that people spend approximately 90 % of their time indoors, indoor air quality is a significant concern. The present study aimed to examine the influence of outdoor particulate matter (PM) levels on indoor PM levels during Asian dust events under everyday conditions.

Methods

We simultaneously monitored counts of particles larger than 0.3, 0.5, 1, 2, and 5 μm using two direct-reading instruments (KC-01D1 airborne particle counter; Rion), one placed in an apartment room and another on the veranda, under everyday conditions before and during an Asian dust event. We also examined how indoor particle counts were affected by opening a window, crawling, and air purifier use.

Results

An Asian dust event on 24 April 2012 caused 50- and 20-fold increases in PM counts in outdoor and indoor air, respectively. A window open for 10 min resulted in a rapid increase of indoor PM counts up to 70 % of outside levels that did not return to baseline levels after 3 h. An air purifier rapidly reduced PM counts for all particle sizes measured.

Conclusions

It is important to account for occupant behavior, such as window-opening and air purifier use, when estimating residential exposure to particulate matter.     

济宁市市区居民PM2.5相关知识知晓情况调查

目的分析济宁市居民对PM2.5相关知识知晓情况,为政府以及相关部门制定科学合理的政策及措施提供科学依据。方法 2013年4月对400名调查对象进行问卷调查。调查居民对PM2.5的主要来源、化学成分、健康危害等的认知情况,对空气质量的关注程度,济宁雾霾天气的好发季节,在雾霾天气时所采取的防护措施以及对如何有效减少雾霾天气的建议和意见。根据数据类型采用统计描述、t检验、单因素方差分析等统计学方法,P0.05为差异有统计学意义。结果发放问卷400份,实际收回369份,有效问卷369份,回收率为92.3%。被调查的369名居民中,关于PM2.5主要来源完全了解的70名,占19.0%;非常了解的107名,占29.0%;一般了解的163名,占44.2%;完全不了解的29名,占7.8%。关于化学成分完全了解的12名,占3.3%;非常了解的42名,占11.4%;一般了解的256名,占69.4%;完全不了解的59名,占15.9%。对PM2.5的健康危害认知平均得分(3.01±1.87)分。不同性别的居民对PM2.5健康危害认知得分差异无统计学意义(P0.05),不同年龄、文化程度、职业的居民对PM2.5健康危害认知的得分差异均有统计学意义(F=2.332、3.906、3.409,均P0.05)。被调查的369名居民中在雾霾天气时绝大多数人都采取了相应的防护措施,未采取任何防护措施仅42名,占11.4%。结论政府和相关部门有必要加强雾霾天气危害的宣传力度和采取相关措施,引起社会各方重视,提高居民在雾霾天气时的防护意识。     

2012年北京市丰台区公共场所集中空调通风系统卫生状况调查

目的调查分析2012年北京市丰台区公共场所集中空调通风系统卫生状况,探讨其影响因素并为卫生管理提供技术支持。方法依据《公共场所集中空调通风系统卫生规范》,检测集中空调送风中细菌总数、真菌、β-溶血性链球菌及PM10,风管内表面细菌总数、真菌总数、积尘量,冷却（凝）水中嗜肺军团菌。结果丰台区集中空调通风系统送风中细菌总数、真菌总数、β-溶血性链球菌、PM10合格率分别为61.42%、88.89%、100.00%、90.91%,风管内表面积尘量、细菌总数、真菌总数合格率分别为100.00%、100.00%、99.20%,冷却（凝）水中嗜肺军团菌合格率为98.20%,血清分型以LP1型为主。集中空调送风中细菌总数存在着明显的季节性差异（χ^2=12.338,P〈0.01）,而送风中真菌、PM10未见明显的季节性差异（χ^2=3.155,P〉0.05;χ^2=6.976,P〉0.05）。不同类型集中空调送风中细菌总数、真菌未见明显差异（χ^2=5.782,P〉0.05;χ^2=2.653,P〉0.05）。结论细菌总数、真菌总数、PM10是丰台区集中空调送风卫生质量的主要影响因素,应加强集中空调管理,定期清洗消毒,并主动开展卫生委托监测。