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101.
The effects of obesity and smoking in the coronavirus disease 2019 (COVID-19) pandemic remain controversial. Angiotensin converting enzyme 2 (ACE2), a component of the renin-angiotensin system (RAS), is the human cell receptor of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of COVID-19. ACE2 expression increases on lung alveolar epithelial cells and adipose tissue due to obesity, smoking and air pollution. A significant relationship exists between air pollution and SARS-CoV-2 infection, as more severe COVID-19 symptoms occur in smokers; comorbid conditions due to obesity or excess ectopic fat accumulation as underlying risk factors for severe COVID-19 strongly encourage the virus/ACE2 receptor-ligand interaction concept. Indeed, obesity, air pollution and smoking associated risk factors share underlying pathophysiologies that are related to the Renin-Angiotensin-System in SARS-CoV-2 infection. The aim of this review is to emphasize the mechanism of receptor-ligand interaction and its impact on the enhanced risk of death due to SARS-CoV-2 infection. 相似文献
102.
The rapid growth in the number of older adults has many implications for public health, including the need to better understand the risks posed by environmental exposures. Aging leads to a decline and deterioration of functional properties at the cellular, tissue and organ level. This loss of functional properties yields to a loss of homeostasis and decreased adaptability to internal and external stress. Frailty is a geriatric syndrome characterized by weakness, weight loss, and low activity that is associated with adverse health outcomes. Frailty manifests as an age-related, biological vulnerability to stressors and decreased physiological reserves. Ambient air pollution exposure affects human health, and elderly people appear to be particularly susceptible to its adverse effects.The aim of this paper is to discuss the role of air pollution in the modulation of several biological mechanisms involved in aging. Evidence is presented on how air pollution can modify the bidirectional association between successful and pathological aging throughout the frailty conditions. 相似文献
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Patrycja Kierlik Aneta Hanc-Kuczkowska Marzena Rachwa Ryszard Mczyski Izabela Matua 《Materials》2020,13(22)
The main objective of the presented preliminary study was the identification of iron-containing phases. Iron-containing phases had accumulated in organic topsoil horizons collected from an area that has long been affected by the steel industry and emissions from power plants. X-ray diffraction and Mössbauer spectroscopy methods were used for the determination of the iron-containing mineral phases in topsoil subsamples which, after two-staged separation, varied in terms of magnetic susceptibility and granulometry. The Mössbauer spectra were recorded using paramagnetic and magnetic components, although the latter occurred only in the strongly magnetic fraction. The central part of spectra was fitted by two doublets (D1 and D2), which were identified as aluminosilicates. Simultaneously, the experimental spectra were described using several Zeeman sextets (Z1, Z2, and Z3) corresponding to the occurrence of hematite and magnetite-like phases with iron in tetrahedral and octahedral sites. Identification of magnetic phases in the tested material, including hematite, led to the conclusion that soil contamination in the studied area was presumably caused by emissions from a nearby power plant. Magnetite-like phases with a different iron content detected in topsoil samples could be related to metallurgical and coking processes, reflecting the specificity of the industrial area from which the samples were taken. The specific composition of the iron-containing aluminosilicates also illustrated the intense and long-lasting impact of the steel and coking industries on the studied area. 相似文献
106.
Haosheng Mu Shinji Otani Mikizo Okamoto Yae Yokoyama Yasuko Tokushima Kazunari Onishi Takenobu Hosoda Youichi Kurozawa 《Yonago acta medica》2014,57(4):133-136
Background
The air quality index (AQI) is widely used to characterize the quality of ambient air. Chinese cities officially report the AQI on a daily basis. To assess the possible effects of air pollution on daily outpatient visits, we examined the association between AQI and the daily outpatient count.Methods
Daily data on outpatient visits to each clinical department were collected from the Z county hospital of Datong City, China. The collection period was between 5 April and 30 June, 2012. Daily AQI data and meteorological information were simultaneously recorded. We compared outpatient counts between the index days and comparison days, and calculated Pearson’s product moment correlation coefficient between outpatient counts and AQI levels.Results
The average AQI level for index days was significantly higher than that for comparison days. No significant difference was observed in temperature or relative humidity between index days and comparison days. The outpatient counts for pediatrics were significantly higher on index days than on comparison days, and no significant difference was noted in other clinical departments. The outpatient counts for pediatrics positively correlated with the AQI level, and no correlation was noted in other clinical departments.Conclusion
The present study assessed the association between daily outpatient visits and air pollution using AQI. The results obtained suggest that air pollution could increase the outpatient count for pediatrics. 相似文献107.
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109.
目的眉山市主城区大气颗粒物污染及对儿童呼吸系统的影响。方法根据2017年眉山市环境监测资料结合空气质量指数选取东坡区(PM 2.5>75μg/m 3)为污染区、彭山区(PM 2.535~75μg/m 3)为相对污染区、岷东新区(PM 2.5<35μg/m 3)为清洁区,在不同区域各选取1所小学,选取8~13岁的儿童及其家长各100例进行研究。对三组儿童进行肺功能检测、体格检查及《儿童呼吸系统疾病流行病学调查问卷》(ATS-DLD-78-C)。结果本次调查共发放问卷300份,回收有效问卷286份,回收有效率为95.33%。三组患儿性别、年龄、身高、体重对比差异无统计学意义(P>0.05)。清洁区FVC、FEV 1明显高于污染区及相对污染区,相对污染区儿童FVC、FEV 1、指标优于污染区(P<0.05)。不同污染区MMEF、V75、V50对比差异无统计学意义(P>0.05)。三组儿童咳嗽、呼吸困难及慢性支气管炎发生率对比差异无统计学意义(P>0.05)。污染区咯痰、哮喘、喘鸣、支气管炎发生率明显高于相对污染区与清洁区(P<0.05),相对污染区与清洁区咯痰、哮喘、喘鸣、支气管炎发生率对比差异无统计学意义(P>0.05)。结论眉山市主城区颗粒污染物对儿童大气道肺功能影响明显,而对小气道功能无显著影响,颗粒污染物可增加儿童呼吸道疾病患病率,提示眉山市主城区颗粒物污染为儿童呼吸系统健康的危险因素之一。 相似文献
110.
Asthma is a phenotypically heterogeneous disorder of multifactorial origins that affects 300 million people suffering from asthma and more than 250,000 asthma-related deaths each year. Although treatment for asthma has improved, its prevalence continues to increase, particularly in low and middle income countries, or in some ethnic groups in which prevalence was previously low. Observed spatio-temporal variations in the increased prevalence of asthma depend on exposure to environmental factors. Recently, several arguments are also in favor of the involvement of host susceptibility and stress in the observed increase of asthma prevalence. Further?investigations are warranted to better understand mechanisms underlying asthma increase or stagnation. 相似文献