Epidemiological studies have shown that there is a link between asthma and brain damage,but toxicological studies have not fully confirmed yet,especially the effects of asthma on the brain. In this study,at first,we explore the effects of asthma on the brain through the establishment of an allergic asthma model. Then PM_(2.5),a typical outdoor air pollutant and formaldehyde,a typical indoor air pollutant were selected to be closer to the true environment and find whether there is any synergism between them. In this study,an ovalbumin( OVA)-sensitized mice asthma model was established. 30 male Balb/c mice were randomly divided into 5 groups:( 1) saline control group,( 2) OVA-sensitized group,( 3) OVA-combined with formaldehyde exposure group,( 4) OVA-combined with PM_(2.5) exposure group,( 5) Combination of OVA,formaldehyde and PM_(2.5) exposure group. The mice were inhaled with formaldehyde or/and instilled with PM_(2.5) from day 1 to 18. The mice asthma model was developed by OVA sensitization and challenge. The mice were sensitized with OVA+Al( OH)3( 5 mg OVA and 175 mg Al( OH)3 in 30 m L saline each time) or saline( 30 m L saline each time) by intraperitoneal injection on day 1,7 and 14.This was then followed by an aerosol challenge in 1% OVA( 30 min·d~(-1)) from day 19 to 25( 7 times) using an ultrasonic nebulizer. On the 26 th day,the organ coefficient of mice brain was counted,then the contents of oxidative stress of mice brain were measured,including reactive oxygen species( ROS),glutathione( GSH) and malondialdehyde( MDA),and the concentrations of NF-κB and interleukin-1β( IL-1β) were detected by using ELISA kits.Detection of interleukin-6( IL-6) was made with immunohistochemical method. Histological assay for brain was also conducted. In our results,all the OVA treated groups showed a significant increase of ROS and a significant decrease of GSH contents when compared with the control group. Except OVA-sensitized group,other OVA treated groups also showed a significant increase of MDA contents when compared with the control group,and MDA contents of OVA-sensitized group showed significant change when compared to the combined exposure group. In ROS and GSH,combined exposure showed some joint effect compared with single exposure. When OVA was applied in combination with formaldehyde and PM_(2.5),NF-κB was activated. And all the OVA treated groups showed increased levels of IL-1β and IL-6 compared with the control group. And the combined exposure showed an aggravated effect when compared with OVA-sensitized group. Histopathological observation of the hippocampus in mice brain clearly showed the difference of eosin( EO) stained neurons in the combined exposure group compared with the control group and OVA-sensitized group. The pyramidal neurons of the mice with allergic asthma exposed to formaldehyde and/or PM_(2.5) had been reduced in number,the cells were swollen and the dendrites had disappeared. Allergic asthma can cause damage to the brain through oxidative stress. Exposure to formaldehyde and PM_(2.5) will increase the damage caused by allergic asthma to the brain,which may be mediated by oxidative stress and NF-κB activation.This promotes the release of the inflammatory factors,resulting in increased inflammation. 相似文献
The applicability of a novel procedure for the disinfection of microbiologically polluted waters from fish-farming ponds, based on the combined action of visible light (including sunlight) and porphyrin-type photosensitising agents, has been investigated using (a) cell cultures of a Gram-positive bacterium (meticillin-resistant Staphylococcus aureus), a Gram-negative bacterium (Escherichia coli) and a fungal pathogen (Saprolegnia spp.); (b) pilot aquaculture plants involving either spontaneously or artificially Saprolegnia-infected rainbow trout (Oncorhynchus mykiss). The results obtained by using two cationic porphyrins, namely a tetra-substituted N-methyl-pyridyl-porphine (C1) and its analogue where one N-methyl group had been replaced by a N-tetradecyl chain (C14), and low intensity visible light irradiation showed an extensive (up to 6-7 log) decrease in the bacterial/fungal population after short incubation and irradiation times in the presence of micromolar photosensitiser concentrations. Moreover, C14 showed some toxic effect also in the absence of light. Extension of these studies to the pilot plants indicated that both C1 + light and C14 can prevent Saprolegnia infections or promote the cure of saprolegniasis in infected trout by treatments with submicromolar porphyrin doses. The procedure appears to be of low cost and to have a low environmental impact. 相似文献
Managing Construction and demolition waste (CDW) is a severe and growing urban challenge, particularly in post-conflict countries. Though Kosovo has significantly rebuilt and developed after the Liberation War, these initiatives have accompanied suboptimal waste management. This research evaluates CDW management in Kosovo by assessing current practices and operations vis-a-vis the legal framework and EU requirements. It identifies instruments and policies capable of ameliorating gaps and proposes a more sustainable and circular CDW management system for Kosovo. Information was primarily collected during on-site visits to Pristina and the surroundings by a cohort of Urban Management Students from the Technische Universität Berlin, students from Kosovo, and the local office of the Gesellschaft für Internationale Zusammenarbeit, GIZ. The analysis identified gaps in Kosovo's CDW management and its observance and enforcement of existing CDW legislation, including an ambiguous licensing system impeding sustainable demolition, storage, and transport; the absence of approved CDW storage options leading to uncontrolled disposal; and an underdeveloped market for recycling and reuse, deterring stakeholders from further pursuit of circular practices. These gaps were compounded by poor recordkeeping, obscuring precise information on CDW streams. Possible instruments and incentives to support Kosovo's transition to a more sustainable CDW management system were then identified.
Environmental Chemistry Letters - Worldwide contamination of waters by metals, metalloids, and organometallic pollutants is a major health issue. In particular, the occurrence of the selenium... 相似文献