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311.
● Metabolome can distinguish pregnant women exposure to PFOA at different degrees. ● Metabolome can reveal the metabolic changes of pregnant women exposure to PFOA. ● PFOA exposure degrees could affect the GSH metabolism of pregnant women. ● PFOA exposure degrees could change the microbiota metabolism of pregnant women. Perfluorooctanoic acid (PFOA) is a novel type of persistent synthetic organic pollutant, and its exposure on pregnant women can cause some adverse effects, such as pregnancy-induced hypertension, gestational diabetes mellitus, and preeclampsia. Therefore, understanding the metabolic changes caused by PFOA exposure is of great significance to protect pregnant women from its adverse effects. In this study, the metabolomes from the urine samples of pregnant women exposure to PFOA at different degrees were analyzed by GC-MS and LC-MS. The samples in different groups were distinguished and the differential metabolites were screened based on the VIP value, FC, and P-value of each comparison group through multivariate statistical analysis. The pathways related to differential metabolites were searched to reveal the effects of PFOA exposure on metabolic changes in pregnant women at different degrees. Finally, the ROC of differential metabolites was performed, and the differential metabolites with large area under the curve (AUC) values were selected and compared to identify the mutually differential metabolites. Meanwhile, these metabolites were fitted with a multivariable to explore if they could be used to distinguish different groups. The quantitative comparison of mutually differential metabolites revealed that the levels of L-cysteine, glycine, and 5-aminovaleric acid were positively correlated with the degree of PFOA exposure, indicating that different degrees of PFOA exposure could affect the synthesis or degradation of GSH and change the metabolism of oral or intestinal microbiota. Additionally, they may cause oxidative stress and abnormal fat metabolism in pregnant women.  相似文献   
312.
In light of the accelerated aging of the global population and the deterioration of the atmosphere pollution, we sought to clarify the potential mechanisms by which fine particulate matter (PM2.5) can cause cognitive impairment and neurodegeneration through the alteration of mitochondrial structure and function. The results indicate that PM2.5 inhalation reduces ATP production by disrupting the aerobic tricarboxylic acid cycle and oxidative phosphorylation, thereby causing the hypophosphorylation of tau in the cortices of middle-aged mice. Furthermore, excessive reactive oxygen species generation was involved in the impairment. Interestingly, these alterations were partially reversed after exposure to PM2.5 ended. These findings clarify the mechanism involved in mitochondrial abnormality-related neuropathological dysfunction in response to atmospheric PM2.5 inhalation and provide an optimistic sight for alleviating the adverse health outcomes in polluted areas.  相似文献   
313.
Optimizationofexperimentalconditionsinstudiesonmetabolismof4nitrobiphenylSongNing,XuXiaoaiResearchCenterforEcoEnvironment...  相似文献   
314.
315.
经叔-丁基-羟基-苯甲醚(BHA)对照、HPLC分析结果表明,天然化合物如从甜瓜蒂(Cucumis melo L. cucurbitaceae)提取的葫芦素B、从徐长卿根(Pycnostelma paniculatum(Bge)K.Shum)提取的牡丹酚、人工合成的对乙氧基苯酚及维生素E中间体2,3,5-三甲基氢醌对BaP在大鼠肝微粒体体外代谢均有不同程度的抑制作用。当其浓度为25μM时,对BaP9,10-二醇及9-OHBaP的生成抑制较对BaP7,8-二醇及BaP4,5-二醇的更强。  相似文献   
316.
Cypermethrin (CYP), a prototypical synthetic pyrethroid, reportedly causes metabolic disruption, while its stereoselective impact remains elusive. This study initially revealed that only α-CYP caused significant weight loss at 8.5 mg/(kg•day) in rats. All three CYP isomers caused the accumulation of hepatic glycogen, and hyperlipemia phenotype as the increment of total triglyceride. Rats treated with α-CYP had markedly high blood glucose levels and homeostasis model assessment of insulin resistance index. The systematic inflammation of θ-CYP group rats was evidenced by high lipopolysaccharide-binding protein levels and abnormalities of leukocytes indices. By examining the gut microbiome, we found that α-CYP-treated rats had low contents of Firmicutes and high levels of Verrucomicrobia while Elusimicrobia was enriched in the β-CYP group. The increasing alpha diversity in the θ-CYP group may be due to the dominance of pathogenic bacteria and the increase of probiotics to counteract adverse effects. Exclusively, the α-CYP group enriched total short-chain fatty acids (SCFAs), whereas most SCFAs depleted in the θ-CYP group. The correlation analysis further found Firmicutes, an energy storage modulator, was positive to body weight (BW), while SCFAs exerted the opposite, confirming the low BW in α-CYP. Blood glucose that correlated well with SCFAs and Verrucomicrobia can be accounted for the discrepancy between α-CYP and θ-CYP. Overall, the three isomers exerted stereoselective glycolipid disruption in rats, and gut homeostasis acted as vital indicators.  相似文献   
317.
铜对小麦氮素代谢的影响李延(浙江农业大学土化系,杭州310029)黄毅斌(福建农科院土肥所,福州350013)秦遂初(浙江农业大学土化系,杭州310029)铜在1931年由A.Sommer证实为植物生长的必需元素。近年来,随着生产集约化程度的提高和耕...  相似文献   
318.
中药青蒿的生理生化特征及其研究进展   总被引:28,自引:0,他引:28  
中药青蒿即黄花蒿 (ArtemisiaannuaL .) ,与分类学上的青蒿 (Artemisiaapiacea)同属菊科 (AsteraceaeorCompositae)蒿属(Artemisia) ,两者均为一年生草本植物且形态上非常相似 ,最明显的区别是黄花蒿的叶片为三回羽状全裂 ,而青蒿为二回羽状全裂 .青蒿广泛分布于全国各地 ,多生于海拔 40 0m以下的丘陵平地[1] .现在这种植物广泛分布于世界各地[2 ] .青蒿在许多地区被用于编制花环 ,提取香料 ,更重要的是从青蒿中分离出的青蒿素是所有抗疟药中起效最快、疗效最好、毒性最低…  相似文献   
319.
土壤含水层处理去除可吸附有机卤化物的试验研究   总被引:14,自引:0,他引:14  
研究了土壤含水层处理工艺对典型城市二级出水以可吸附有机卤化物表征的有机物的去除效果。投加24mg/l臭氧预处理后,再经好氧含水层处理可去除约32%的AOX,厌氧柱进水中投加各80mg/l葡萄糖和谷氨酸,运行稳定性,通过共谢作用,可去除约55%的AOX。  相似文献   
320.
采集渭河沉积物及西安某自备井的地下水,沉积物采用逐级分离法处理后,进行厌氧微宇宙实验,研究反硝化条件下河流沉积层中苯胺降解及有机碳与水合金属氧化物的影响.结果表明,硝酸盐为50、300或400mg·L-1,沉积物中的原有或外加的有机碳都对苯胺降解具有抑制作用;去碳沉积物、去碳去金属沉积物实验中,硝酸盐为50mg·L-1时,外加有机碳具有抑制作用,当硝酸盐为300或400 mg·L-1时则有促进作用.去碳沉积物与去碳去金属沉积物的实验发现,无论是否有外加有机碳,水合金属氧化物都对河床沉积层中反硝化条件下苯胺降解具有促进作用.机理分析表明,反硝化条件下,河流沉积层中的微生物以生长代谢的方式利用苯胺,使其降解.苯胺降解经过脱氨基过程.  相似文献   
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