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1.
Asthma and PM10     
PM10 (the mass of particles present in the air having a 50% cutoff for particles with an aerodynamic diameter of 10 μm) is the standard measure of particulate air pollution used worldwide. Epidemiological studies suggest that asthma symptoms can be worsened by increases in the levels of PM10. Epidemiological evidence at present indicates that PM10 increases do not raise the chances of initial sensitisation and induction of disease, although further research is warranted. PM10 is a complex mixture of particle types and has many components and there is no general agreement regarding which component(s) could lead to exacerbations of asthma. However pro-inflammatory effects of transition metals, hydrocarbons, ultrafine particles and endotoxin, all present to varying degrees in PM10, could be important. An understanding of the role of the different components of PM10 in exacerbating asthma is essential before proper risk assessment can be undertaken leading to advice on risk management for the many asthmatics who are exposed to air pollution particles.  相似文献   

2.
PM2.5和PM10已成为我国大部分城市空气的首要污染物.本文通过分析南昌市2013—2015年的空气PM2.5和PM10质量浓度、气象因素、交通流量的监测数据,探讨了空气颗粒物污染的时空动态规律以及气象、交通对颗粒物浓度变化的影响.结果表明: 2013、2014、2015年,南昌市PM2.5浓度(70.92 μg·m-3>53.70 μg·m-3>43.65 μg·m-3)、PM10浓度(119.72 μg·m-3>86.11 μg·m-3>73.32 μg·m-3)逐年降低,并呈现出夏季低(PM2.5和PM10平均浓度分别为36.74、69.20 μg·m-3)、冬季高(PM2.5和PM10平均浓度分别为74.29、111.64 μg·m-3)的季节动态和由城市中心向郊区递减的城乡梯度变化; PM2.5/PM10值(0.595>0.584>0.557)逐年降低,并且表现出城市中心高、城市边缘低的空间分布格局;PM2.5、PM10浓度受到多种气象因素的影响,与气压、温度、相对湿度、风速、降水量、日照时数显著相关,各种气象因子对PM2.5、PM10浓度的影响存在差异;车流量会显著提高周边PM2.5浓度,但对PM10浓度影响不明显.  相似文献   

3.
Daily levels of particulate matter (PM) in the ambient air (PM 2.5 and PM 10) were measured in a northern city of Thailand (Chiang Mai) from March 1998 to October 1999. Twenty-four-hour air particulate matter samples were collected each day with Airmetric Minivol portable air samplers. Monthly averages of PM 2.5 from four stations in Chiang Mai varied from 15.39 to 138.31microg/m(3) and 27.29 to 173.40 microg/m(3) for PM 10. The PM 2.5 annual average was 58.48 mg/m(3) and PM 10, 86.38 microg/m(3). Daily PM 2.5 (24h values) during the winter months in Chiang Mai frequently exceeded 200-300 microg/m(3). The maximum concentrations of PM 2.5 (24h average) in Chiang Mai air from December 1998 to April 1999 were 2.8-, 3.5-, 4.2-, 6.5- and 3.2-fold higher than the US Environmental Protection Agency (US EPA), PM 2.5, 24h standard of 65 microg/m(3). From May to October, the mean 24h levels of PM 2.5 and PM 10 were at acceptable levels. The data shows that during the winter season (December to March), levels of PM 2.5 and PM 10 in the Chiang Mai atmosphere are very high, and there may be significant health implications associated with these high concentrations. During the summer season, the fine particles were generally within the acceptable levels. To our knowledge, these are the first measurements of PM 2.5 to be reported for the city of Chiang Mai and they indicate considerable ambient fine particle exposures to the Chiang Mai population. In addition, dichloromethane extracts of airborne particulate matter PM 2.5 or PM 10 collected in the months of winter in the city of Chiang Mai were mutagenic to Salmonella typhimurium strain TA100 without metabolic activation. The mutagenicity appeared to track particle concentrations and increased in the presence of S9 mix.  相似文献   

4.
In this study, we have estimated the number of total mortality (T-mortality), cardiovascular morbidity (CV-mortality), respiratory mortality (R-mortality), hospital admissions due to cardiovascular diseases (HA-CVD), respiratory diseases (HA-RD), chronic obstructive pulmonary diseases (COPD) and acute myocardial infarction (AMI) due to exposure to particulate matter less than 10 µm (PM10), 2.5 µm (PM2.5) and sulfur dioxide (SO2) in western Iran in 2016. The World Health Organization (WHO) method was used to assess the mortality and morbidity among the exposed people. The results showed that about 3.9% CM (95% CI: 2.9–7.8%), 3.9% HA-RD (95% CI: 2.4–7.8%) and 4.4% HA-CVD (95% CI: 3.0–6.8%) for ambient PM10 and about 7.3% TM (95% CI: 4.2–9.7%), 12.1% CM (95% CI: 3.5–14.6%) and 3.0% RM (95% CI: 0–6.3%) for PM2.5 are respectively attributed to concentrations exceeding 10 µg/m3. Furthermore, 3.2% HA-COPD (95% CI: 0–5.04%) and 4.2% AMI (95% CI: 1.6–4.3%) can be attributed to SO2 concentrations greater than 10 µg/m3, respectively. To reduce the adverse health effect of PM, health advices provided by health authorities should be given to general population especially vulnerable people such as people with chronic lung and heart pathologies, elderly and children during the dusty days.  相似文献   

5.
The aim of this study is to survey the PM10, PM2.5, and PM1 concentrations in rural and urban areas in Tehran province during cold, warm and dust storm days from December 22, 2016 to June 5, 2017 using Grimm Model aerosol spectrometer. During the study period, daily PM10, PM2.5, and PM1 concentrations ranged from 27.2 to 244.96, 8.4 to 77.9, and 6.5 to 56.8 μg/m3 in urban sites, and 22.8 to 286.4, 6 to 41.1, and 2.1 to 20.2 μg/m3 in rural parts, respectively. Particularly, both daily WHO limits for outdoor PM10 (50.0 μg/m3) and PM2.5 (25.0 μg/m3) exceeded in 95% and 83% of the outdoor measurements in winter and 82% and 58% in total sampled days in urban site, respectively. The 24-h average PM10 and PM2.5 concentrations also exceeded by 59% and 18% in winter and by 36% and 14% of all sampling days in rural site, respectively. During the dust storm, the 24-h average PM10, PM2.5, and PM1 concentrations were, respectively 4.7, 2, and 1.96 times higher than those in urban site and 2, 1.7, and 1.3 times more than those in rural site in all sampled days.  相似文献   

6.
目的:探讨长沙市大气可吸入颗粒物(PM10)与脑卒中急诊的相关性。方法:收集2008-2009年间长沙市每日脑出血和脑梗死急诊数据,同期收集长沙市大气可吸入颗粒物(PM10)及相关气象数据,利用季节分层的单向回顾性1:1配对病例交叉研究设计,建立单污染物模型和多污染物模型进行分析。结果:在调整气温和相对湿度的单污染物滞后模型中,秋季滞后0、1、2天的PM10日均浓度每增加10μg/m3,与脑出血和脑梗死的的OR(95%CI)值分别为0.953(0.871-1.042)和0.970(0.910-1.034)、0.984(0.913-1.061)和0.965(0.902-1.031)、0.996(0.928-1.069)和0.964(0.904-1.029),关联具有统计学意义(P0.05)。结论:长沙市PM10浓度变化对脑卒中发病有影响。  相似文献   

7.

Background

Asthma is characterized by type 2 T-helper cell (Th2) inflammation, goblet cell hyperplasia, airway hyperreactivity, and airway fibrosis. Monocyte chemoattractant protein-1 (MCP-1 or CCL2) and its receptor, CCR2, have been shown to play important roles in the development of Th2 inflammation. CCR2-deficient mice have been found to have altered inflammatory and physiologic responses in some models of experimental allergic asthma, but the role of CCR2 in contributing to inflammation and airway hyperreactivity appears to vary considerably between models. Furthermore, MCP-1-deficient mice have not previously been studied in models of experimental allergic asthma.

Methods

To test whether MCP-1 and CCR2 are each required for the development of experimental allergic asthma, we applied an Aspergillus antigen-induced model of Th2 cytokine-driven allergic asthma associated with airway fibrosis to mice deficient in either MCP-1 or CCR2. Previous studies with live Aspergillus conidia instilled into the lung revealed that MCP-1 and CCR2 play a role in anti-fungal responses; in contrast, we used a non-viable Aspergillus antigen preparation known to induce a robust eosinophilic inflammatory response.

Results

We found that wild-type C57BL/6 mice developed eosinophilic airway inflammation, goblet cell hyperplasia, airway hyperreactivity, elevations in serum IgE, and airway fibrosis in response to airway challenge with Aspergillus antigen. Surprisingly, mice deficient in either MCP-1 or CCR2 had responses to Aspergillus antigen similar to those seen in wild-type mice, including production of Th2 cytokines.

Conclusion

We conclude that robust Th2-mediated lung pathology can occur even in the complete absence of MCP-1 or CCR2.  相似文献   

8.
Hsiao WL  Mo ZY  Fang M  Shi XM  Wang F 《Mutation research》2000,471(1-2):45-55
Ambient air particulate matters are classified into two distinct modes in size distribution, namely the coarse and fine particles. Correlation between high particulate concentration and adverse effects on human populations has long been recognized, however, the toxicology of these adverse effects has not been clarified. In the current report, the cytotoxic effects of the solvent-extractable organic compounds (SEOC) from fine particles smaller than 2.5 microm (PM(2.5)) and from coarse particles between 2.5-10 microm (PM(2.5-10)) were studied. Nine 24h consecutive monthly samples were tested to determine the correlation between cytotoxicity and total SEOC in two size fractions of particulate air pollution. Cytotoxicity of SEOC was measured by two micro-scale mammalian cells-based bioassays: the MTT cell proliferation assay, and the Comet assay for the detection of DNA damage. A well-defined mammalian cell line - Rat 6 rodent fibroblast was employed in the study. The SEOC extracts of air particulate matters were sub divided into two equal parts. One part was dissolved in DMSO, the other in KOH/hexane and then conjugated with bovine serum albumin to produce a lipid-soluble fraction for testing. The DMSO fraction would contain mainly the polycyclic aromatic hydrocarbons (PAH), alkanes and alkanols, while the lipid-soluble fraction would be enriched with fatty acids. The results from MTT assay showed that cytotoxicity of the PM(2.5) was much more severe than the PM(2.5-10), suggesting that toxic SEOC were confined to the fine particles. By and large, the DMSO solubles were much more toxic than the lipid solubles. The degree of cytotoxicity of the DMSO soluble samples is positively correlated to the amount of particulates present in the ambient air. For the PM(2.5), the winter samples were significantly more toxic than the summer samples in terms of cell killing, which seemed to be a direct reflection of the total loading of organic matter in the samples. Results from Comet assays showed that SEOC samples of PM(2.5) derived from winter months induced DNA damage at dosages resulting in no obvious cell killing in the MTT assay. Thus, long-term exposure to non-killing dosage of air pollutants may lead to the accumulation of DNA lesions, which may be one of the mechanisms responsible for the chronic adverse health effects of particulate air pollution.  相似文献   

9.
目的:探讨白细胞介素-10(IL-10)启动子-627C/A基因多态性和等位基因频率与过敏性哮喘血清IgE、IL-10浓度以及病情严重程度的相互关系。方法:从哮喘病人DNA文库中选择青岛地区过敏性哮喘病人518例和健康志愿者501例,采用PCR-RFLP方法对IL-10基因启动子-627位点多态性进行观察,比较两组基因型和等位基因的分布频率,同时测定血清中总IgE、IL-10浓度和肺功能检查(FEV1、FVC、FEVl/FVC)。结果:轻度和中-重度哮喘组AA、CA和CC基因型所占比例分别为38.1%、46.0%、15.9%和45.6%、46.2%和8.2%(P=0.0168,X~2=8.232,df=2)A等位基因与哮喘病轻的严重程度有明显相关性(P<0.05)。AA基因型哮喘病人血清的IgE浓度显著升高(P<0.01),但其血清IL-10浓度比CC基因型携带者明显降低(P<0.01)。结论:IL-10基因启动子-627位点多态性与过敏性哮喘的发生有一定的相关性,等位基因A是哮喘患病的风险基因,而等位基因C则是哮喘病的保护基因。  相似文献   

10.
目的:探讨白细胞介素-10(IL-10)启动子-627C/A基因多态性和等位基因频率与过敏性哮喘血清IgE、IL-10浓度以及病情严重程度的相互关系。方法:从哮喘病人DNA文库中选择青岛地区过敏性哮喘病人518例和健康志愿者501例,采用PCR—RFLP方法对IL.10基因启动子.627位点多态性进行观察,比较两组基因型和等位基因的分布频率,同时测定血清中总IgE、IL-10浓度和肺功能检查(FEV1、FVC、FEV1/FVC)。结果:轻度和中一重度哮喘组AA、CA和CC基因型所占比例分别为38.1%、46.0%、15.9%和45.6%、46.2%和8.2%(P=0.0168,X2=8.232,df=2)。A等位基因与哮喘病轻的严重程度有明显相关性(P〈0.05)。AA基因型哮喘病人血清的IgE浓度显著升高(P〈0.01),但其血清IL-10浓度比CC基因型携带者明显降低(P〈0.01)。结论:IL-10基因启动子-627位点多态性与过敏性哮喘的发生有一定的相关性,等位基因A是哮喘患病的风险基因,而等位基因C则是哮喘病的保护基因。  相似文献   

11.
Asthma is a chronic inflammatory lung disease affecting approximately 7.7% of the US population. Sex differences in the prevalence, incidence, and severity of asthma have been widely described throughout the lifespan, showing higher rates in boys than girls before puberty, but a reversed pattern in adults. Asthma is often associated with atopy, i.e. the tendency to develop allergic diseases, and can be worsened by environmental stimuli and/or exercise. While not exclusive to patients with asthma, exercise-induced bronchoconstriction (EIB) is a common complication of athletes and individuals who exercise regularly. Currently, there is limited research on sex differences in EIB and its relationship with atopy and asthma in men and women. In this minireview, we summarize the available literature on this topic. Overall, the collective knowledge supports the notion that physiological changes triggered during exercise affect males and females differently, suggesting an interaction among sex, exercise, sex hormones, and atopic status in the course of EIB pathophysiology. Understanding these differences is important to provide personalized management plans to men and women who exercise regularly and suffer from underlying asthma and/or atopy.  相似文献   

12.
CaMBP-10在活体处理条件下,抑制IAA诱导的质膜H -ATh酶活性及其磷酸化,抑制作用可被IAA逆转并在外加CaM时被消除,与前期BP-10对IAA生理应答的调节效应相吻合。并且在各项处理中,质膜H -ATh酶活性与其磷酸化水平呈现极显著的正相关。结果表明,质膜H -ATh酶活性受其磷酸化的调节,CaMBP-10参与了这一调节过程,它通过介导该酶磷酸化调节其活性,在IAA应答反应中发挥调节功能。  相似文献   

13.
14.
In December 1968 an emergency service was begun in Edinburgh to expedite admission to hospital of patients with severe acute asthma. During the first 10 years requests were made to admit 112 patients to a respiratory unit with provision for intensive care on 360 occasions. Four of the patients died of their disease, one in hospital and three before admission. It was thought that the death rate would have been much higher had conventional admission procedures been observed. Owing to ethical objections to a controlled trial it was not possible to obtain substantive proof that the service reduced deaths from asthma. Nevertheless, there was strong circumstantial evidence that organised facilities for the immediate admission to hospital of patients with a history of life-threatening attacks would result in fewer deaths at home. Earlier admission also apparently reduced hospital mortality and the number of patients requiring tracheal intubation and mechanical ventilation. It is concluded that there is a prima facie case for an emergency asthma admission serivce similar to that operating in Edinburgh to be established in all cities and large towns.  相似文献   

15.
Adverse health effects of air pollution attributed mainly to airborne particulate matter have been well documented in the last couple of decades. Short term exposure, referring to a few hours exposure, to high ambient PM10 concentration is linked to increased hospitalization rates for cardiovascular events, typically 24 h after air pollution peaks. Particulate matter exposure is related to pulmonary and cardiovascular diseases, with increased oxidative stress and inflammatory status. Previously, we have demonstrated that repeated intratracheal instillation of PM10sum in BALB/c mice leads to respiratory tract inflammation, creating in lung a condition which could potentially evolve in a systemic toxic reaction. Additionally, plasma membrane and tissue lipids are easily affected by oxidative stress and directly correlated with inflammatory products. With this aim, in the present investigation using the same model, we analyzed the toxic potential of PM10sum exposure on lipid plasma membrane composition, lipid peroxidation and the mechanisms of cells protection in multiple organs such as lung, heart, liver and brain. Obtained results indicated that PM10 exposure led to lung lipid reshaping, in particular phospholipid and cholesterol content increases; concomitantly, the generation of oxidative stress caused lipid peroxidation. In liver we found significant changes in lipid content, mainly due to an increase of phosphatidylcholine, and in total fatty acid composition with a more pronounced level of docosahexaenoic acid; these changes were statistically correlated to lung molecular markers. Heart and brain were similarly affected; heart was significantly enriched in triglycerides in half of the PM10sum treated mice. These results demonstrated a direct involvement of PM10sum in affecting lipid metabolism and oxidative stress in peripheral tissues that might be related to the serious systemic air-pollution effects on human health.  相似文献   

16.

Objective

To synthesize and determine the antitumor activity of 10-chlorocanthin-6-one in ovarian cancer HO8910PM cells.

Results

Among the synthesized canthin-6-one analogs, 10-chlorocanthin-6-one was the most cytotoxic (IC50 = 4.9 μM), as demonstrated by a dose-dependent cytotoxicity assay. Moreover, 10-chlorocanthin-6-one induced apoptosis through the activation of poly(ADP-ribose) polymerase and caspase-3 cleavage, upregulation of Bcl-2, and downregulation of Bim, x-linked inhibitor of apoptosis protein (XIAP), and survivin in HO8910PM cells. Furthermore, Bim RNA, upregulated in a concentration-dependent manner, and knockdown of Bim via short-hairpin RNAs attenuated the inhibitory effects of 10-chlorocanthin-6-one on HO8910PM cell growth.

Conclusions

10-Chlorocanthin-6-one inhibits cell proliferation and induces apoptosis in H08910PM cells. The underlying molecular mechanisms of 10-chlorocanthin-6-one include activation of the Bim-mediated mitochondrial apoptotic pathway via upregulation of Bim and downregulation of Bcl-2, XIAP, and survivin. These data suggest that Bim is a potential target of 10-chlorocanthin-6-one, further demonstrating its potential use in the prevention and treatment of ovarian cancer.
  相似文献   

17.
This review focuses on the potential role that oxidative stress plays in the adverse effects of PM(10). The central hypothesis is that the ability of PM(10) to cause oxidative stress underlies the association between increased exposure to PM(10) and both exacerbations of lung disease and lung cancer. Pulmonary inflammation may also underlie the cardiovascular effects seen following increased PM(10), although the mechanisms of the cardiovascular effects of PM(10) are not well understood. PM(10) is a complex mix of various particle types and several of the components of PM(10) are likely to be involved in the induction of oxidative stress. The most likely of these are transition metals, ultrafine particle surfaces, and organic compounds. In support of this hypothesis, oxidative stress arising from PM(10) has been shown to activate a number of redox-responsive signaling pathways in lung target cells. These pathways are involved in expression of genes that play a role in responses relevant to inflammation and pathological change, including MAPKs, NF-kappaB, AP-1, and histone acetylation. Oxidative stress from particles is also likely to play an important role in the carcinogenic effects associated with PM(10) and hydroxyl radicals from PM(10) cause DNA damage in vitro.  相似文献   

18.
目的:探讨IL-10基因启动子区-627A/C和IL-17基因启动子-152A/G位点多态性与儿童哮喘发生的相关性。方法:采用聚合酶链反应-限制性片段长度多态性分析(PCR-PFLP)方法检测186名哮喘儿童、198名健康儿童各个多态性位点的基因型,采用SPSS13.0进行统计学分析。结果:IL-17基因-152A/G位点的基因型及等位基因频率分布在哮喘组与正常对照组均存在显著性差异(p<0.05),哮喘组-152A/G位点等位基因A频率显著高于正常对照组(x2=6.077,p=0.014,OR=1.430,95%CI=1.076-1.902)。结论:IL-17基因-152A/G位点可能与儿童哮喘的发病存在关系,其中A等位基因可能是易感基因,携带A的个体可能更易患有哮喘。  相似文献   

19.
魏波  朱莉莉  邓丁芳 《生物磁学》2011,(2):307-309,313
目的:探讨IL-10基因启动子区-627A/C和IL-17基因启动子-152A/G位点多态性与儿童哮喘发生的相关性。方法:采用聚合酶链反应-限制性片段长度多态性分析(PCR-PFLP)方法检测186名哮喘儿童、198名健康儿童各个多态性位点的基因型,采用SPSS13.0进行统计学分析。结果:IL-17基因-152A/G位点的基因型及等位基因频率分布在哮喘组与正常对照组均存在显著性差异(p〈0.05),哮喘组-152A/G位点等位基因A频率显著高于正常对照组(x2=6.077,p=0.014,OR=1.430,95%CI=1.076-1.902)。结论:IL-17基因-152A/G位点可能与儿童哮喘的发病存在关系,其中A等位基因可能是易感基因,携带A的个体可能更易患有哮喘。  相似文献   

20.
Many hospitalizations for asthma could potentially be avoided with appropriate management. The aim of this study was to analyze data on disease management of a paediatric population with a hospitalization for asthma. The study population comprised 6–17 year old subjects belonging to three local health units of the Lombardy Region, northern Italy. Regional administrative databases were used to collect data on: the number of children with an incident hospitalization for asthma during the 2004–2006 period, anti-asthma therapy, specialist visit referrals, and claims for spirometry, released in the 12 months before and after hospitalization. Each patient’s asthma management profile was compared with GINA guideline recommendations. Among the 183 hospitalized subjects, 101 (55%) received therapy before hospitalization and 82 (45%) did not. 10% did not receive any therapy either before or after hospital admission and in 13% the therapy was discontinued afterward. Based on GINA guidelines, asthma management adhered to recommendations only for 55% of subjects. Results may suggest that for half of hospitalized subjects, inaccurate diagnosis, under-treatment/scarce compliance with asthma guidelines by physicians, and/or scarce compliance to therapy by patients/their parents occurred. In all these cases, hospitalization would be a proxy indicator of preventable poor control of disease, rather than a proxy indicator of severity.  相似文献   

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