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Exposure to air pollution interacts with obesogenic nutrition to induce tissue-specific response patterns
2018
Pardo, Michal | Kuperman, Yael | Levin, Liron | Rudich, Assaf | Haim, Yulia | Schauer, James J. | Chen, Alon | Rudich, Yinon
Obesity and exposure to particular matter (PM) have become two leading global threats to public health. However, the exact mechanisms and tissue-specificity of their health effects are largely unknown. Here we investigate whether a metabolic challenge (early nutritional obesity) synergistically interacts with an environmental challenge (PM exposure) to alter genes representing key response pathways, in a tissue-specific manner. Mice subjected to 7 weeks obesogenic nutrition were exposed every other day during the final week and a half to aqueous extracts of PM collected in the city of London (UK). The expression of 61 selected genes representing key response pathways were investigated in lung, liver, white and brown adipose tissues. Principal component analysis (PCA) revealed distinct patterns of expression changes between the 4 tissues, particularly in the lungs and the liver. Surprisingly, the lung responded to the nutrition challenge. The response of these organs to the PM challenge displayed opposite patterns for some key genes, in particular, those related to the Nrf2 pathway. While the contribution to the variance in gene expression changes in mice exposed to the combined challenge were largely similar among the tissues in PCA1, PCA2 exhibited predominant contribution of inflammatory and oxidative stress responses to the variance in the lungs, and a greater contribution of autophagy genes and MAP kinases in adipose tissues. Possible involvement of alterations in DNA methylation was demonstrated by cell-type-specific responses to a methylation inhibitor. Correspondingly, the DNA methyltransferase Dnmt3a2 increased in the lungs but decreased in the liver, demonstrating potential tissue-differential synergism between nutritional and PM exposure. The results suggest that urban PM, containing dissolved metals, interacts with obesogenic nutrition to regulate diverse response pathways including inflammation and oxidative stress, in a tissue-specific manner. Tissue-differential effects on DNA methylation may underlie tissue-specific responses to key stress-response genes such as catalase and Nrf2.
显示更多 [+] 显示较少 [-]Amendment soil with biochar to control antibiotic resistance genes under unconventional water resources irrigation: Proceed with caution
2018
Cui, Er-Ping | Gao, Feng | Liu, Yuan | Fan, Xiang-Yang | Li, Zhong-Yang | Du, Zhen-Jie | Hu, Zhao | Neal, Andrew L.
The spread of antibiotic resistance genes (ARGs) has become a cause for serious concern because of its potential risk to public health. The use of unconventional water resources (e.g., reclaimed water or piggery wastewater) in agriculture to relieve groundwater shortages may result in an accumulation of ARGs in soil. Biochar addition has been proven to be a beneficial method to alleviate the pollution of ARGs in manure-amended soil. However, the role of biochar on ARGs in soil-plant systems repeatedly irrigated with unconventional water resources is unknown. Under reclaimed water or piggery wastewater irrigation, rhizobox experiments using maize plants in soil amended with biochar were conducted to investigate the variation of typical ARGs (tet and sul genes) in soil-plant systems during a 60-day cultivation, and ARGs was characterized by high-throughput qPCR with a 48 (assays) × 108 (samples) array. Only piggery wastewater irrigation significantly increased the abundance of ARGs in rhizosphere and bulk soils and root endophytes. Following 30-day cultivation, the abundance of ARGs in soil was significantly lower due to biochar addition. However, by day 60, the abundance of ARGs in soil supplemented with biochar was significantly higher than in the control soils. Antibiotics, bio-available heavy metals, nutrients, bacterial community, and mobile gene elements (MGEs) were detected and analyzed to find factors shaping ARGs dynamics. The behavior of ARGs were associated with antibiotics but not with bio-available heavy metals. The correlation between ARGs and available phosphorus was stronger than that of ARGs with total phosphorus. MGEs had good relationship with ARGs, and MGEs shifts contributed most to ARGs variation in soil and root samples. In summary, this study provides insights into potential options for biochar use in agricultural activities.
显示更多 [+] 显示较少 [-]Maternal transfer of phenol derivatives in the Baltic grey seal Halichoerus grypus grypus
2018
Nehring, Iga | Falkowska, Lucyna | Staniszewska, Marta | Pawliczka, Iwona | Bodziach, Karina
Studies of circulating levels in difference sex and age classes, and maternal transfer of bisphenol A, 4-tert-octylphenol and 4- nonylphenol in the Baltic grey seal were performed from 2014-2017. Blood was collected from long-term captive adult males, pregnant females and pups. Milk was collected from nursing females. The aim of this study was not only to determine the concentrations of phenol derivatives, i.e. bisphenol A (BPA), 4-tert-octylphenol (OP) and 4-nonylphenol (NP), but also to try to evaluate the transfer of these compounds to the next generation in the final stage of foetal life and in the first few weeks of life in juvenile marine mammals. The measurements were carried out using high performance liquid chromatography. The obtained data show that all phenol derivatives are present in the blood of males, females and pups (range <0.07–101 ng·cm⁻³) and in female milk (range <0.1–406.3 ng·cm⁻³). The main source of phenol derivatives in organisms is food exposure. Gender, age, or number of births were not observed to have a significant effect on changes in phenol derivative levels in seal blood within the breeding group. In the prenatal stage of life, a small amount of BPA and alkylphenols was passed on to the offspring through the placenta. In the blood of the offspring the concentration of these compounds exceeded the concentration in the mother's blood 1.5-fold. During nursing, females detoxified their systems. Level of phenol derivatives in the pups blood increased linearly with its increasing concentrations in the mother's milk. On the other hand, the seafood diet which started after the physiological fasting stage of the pup, stabilised the levels of phenol derivatives below 10 ng ∙ cm⁻³.
显示更多 [+] 显示较少 [-]Associations between lipid/lipoprotein levels and perfluoroalkyl substances among US children aged 6–11 years
2018
Jain, Ram B. | Ducatman, Alan
Observed levels of lipid/lipoproteins are known to be associated with exposure to perfluoroalkyl substances (PFAS). In order to evaluate and update these associations among US children aged 6–11 years, data (N = 458) from National Health and Nutrition Examination Survey for 2013–2014 were used. The associations between the observed levels of total cholesterol, high density lipoprotein (HDL) cholesterol, and non-HDL cholesterol and selected PFAS were studied. PFAS data were available for perfluorononanoic acid (PFNA), perfluorohexane sulfonate (PFHxS), linear isomer of perfluorooctanoic acid (PFOA), linear isomer of perfluorooctane sulfonate (PFOS), monomethyl branch isomer of PFOS, and sum of PFAS. Regression models were fitted to evaluate these associations. A statistically significant (p = 0.03) positive association between the levels of linear isomer of PFOS and total cholesterol was observed. A 10% increase in the levels of linear isomer of PFOS measured in ng/L was found to be accompanied by a 0.03–0.42% increase in the levels of total cholesterol measured in mg/dL. For PFNA, girls in the first quartile of PFNA were found to have lower adjusted levels for total cholesterol than the girls in the fourth quartile of PFNA (152.6 vs. 164.7 mg/dL, p < 0.01). Also, non-Hispanic blacks in the first quartile of PFNA were found to have lower adjusted levels for total cholesterol than the non-Hispanic blacks in the fourth quartile of PFNA (143.4 vs. 160.5 mg/dL, p = 0.04). A negative association between branch isomer of PFOS and non-HDL cholesterol was also observed (β = −0.0066, p = 0.04). The adjusted levels of non-HDL cholesterol were higher in the second quartile of ∑PFAS than in the fourth quartile of ∑PFAS (103.0 vs. 97.5 mg/dL, p < 0.01). Linear PFOS and possibly PFNA are associated with total cholesterol in the most recent NHANES childhood sample. Concentrations of PFAS and associations with cholesterol have both decreased compared to previous literature.
显示更多 [+] 显示较少 [-]Steroidal and phenolic endocrine disrupting chemicals (EDCs) in surface water of Bahe River, China: Distribution, bioaccumulation, risk assessment and estrogenic effect on Hemiculter leucisculus
2018
Wang, Song | Zhu, Zeliang | He, Jiafa | Yue, Xiaoya | Pan, Jianxiong | Wang, Zaizhao
This study investigated selected steroidal and phenolic endocrine disrupting compounds (EDCs) in the surface water of the Bahe River (China) using gas chromatography mass spectrometry (GC-MS). Their effect on the wild sharpbelly Hemiculter leucisculus was investigated. The concentrations of 4-t-octylphenol, nonylphenol, bisphenol-A, estrone, 17 β-estradiol, 17 α-Ethinylestradiol, and estriol were up to 126.0, 634.8, 1573.1, 55.9, 23.9, 31.5, and 5.2 ng L⁻¹ in the surface water, and up to 26.4, 103.5, 146.9, 14.2, 9.3, 13.8, and 1.3 ng g⁻¹ in the fish muscle tissue, respectively. High estrogen equivalent levels and hazard quotients were found in the middle and lower reaches of the river, and the pollution in these regions caused enhanced growth conditions, inhibition of gonad growth, and suppression of spermatogenesis in H. leucisculus. The up-regulation of Vitellogenin mRNA expression in male fish, collected from relatively heavily EDCs contaminated areas, indicates a potential estrogenic effect. The differential expression profiles of genes related to steroidogenesis at all sampling sites suggests that these endpoints may play an important role for the pollution monitoring of estrogenic EDCs in the Bahe River.
显示更多 [+] 显示较少 [-]Ambient air quality in the holy city of Makkah: A source apportionment with elemental enrichment factors (EFs) and factor analysis (PMF)
2018
Nayebare, Shedrack R. | Aburizaiza, Omar S. | Siddique, Azhar | Carpenter, David O. | Hussain, Mirza M. | Zeb, Jahan | Aburiziza, Abdullah J. | Khwaja, Haider A.
Air pollution remains a major global public health and environmental issue. We assessed the levels of PM₂.₅ and delineated the major sources in Makkah, Saudi Arabia. Fine particulate matter (PM₂.₅) sampling was performed from February 26, 2014–January 27, 2015 in four cycles/seasons. Samples were analyzed for black carbon (BC) and trace elements (TEs). PM₂.₅ source apportionment was performed by computing enrichment factors (EFs) and positive matrix factorization (PMF). Backward-in time trajectories were used to assess the long-range transport. Significant seasonal variations in PM₂.₅ were observed, Spring: 113 ± 67.1, Summer: 88.3 ± 36.4, Fall: 67.8 ± 24, and Winter: 67.6 ± 36.9 μg m⁻³. The 24-h PM₂.₅ exceeded the WHO (25 μg m⁻³) and Saudi Arabia's (35 μg m⁻³) guidelines, with an air quality index (AQI) of “unhealthy to hazardous” to human health. Most delta–C computations were below zero, indicating minor contributions from bio-mass burning. TEs were primarily Si, Ca, Fe, Al, S, K and Mg, suggesting major contributions from soil (Si, Ca, Fe, Al, Mg), and industrial and vehicular emissions (S, Ca, Al, Fe, K). EF defined two broad categories of TEs as: anthropogenic (Cu, Zn, Eu, Cl, Pb, S, Br and Lu), and earth-crust derived (Al, Si, Na, Mg, Rb, K, Zr, Ti, Fe, Mn, Sr, Y, Cr, Ga, Ca, Ni and Ce). Notably, all the anthropogenic TEs can be linked to industrial and vehicular emissions. PMF analysis defined four major sources as: vehicular emissions, 30.1%; industrial-mixed dust, 28.9%; soil/earth-crust, 24.7%; and fossil-fuels/oil combustion, 16.3%. Plots of wind trajectories indicated wind direction and regional transport as major influences on air pollution levels in Makkah. In collusion, anthropogenic emissions contributed >75% of the observed air pollution in Makkah. Developing strategies for reducing anthropogenic emissions are paramount to controlling particulate air pollution in this region.
显示更多 [+] 显示较少 [-]RETRACTED: Signalling cross-talk between nitric oxide and active oxygen in Trifolium repens L. plants responses to cadmium stress
2018
Liu, Shiliang | Yang, Rongjie | Tripathi, Durgesh Kumar | Li, Xi | Jiang, Mingyan | Lv, Bingyang | Ma, Mingdong | Chen, Qibing
This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal).This article has been retracted at the request of the Editors-in-Chief.The authors have plagiarized part of a paper that had appeared in Plant, Cell & Environment, 29 (2006) 1532–1544. https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1365-3040.2006.01531.x The images that were reused were: Figures 1e, 1f, 1g, 1h, 2a, 2b, 2e, 2f.One of the conditions of submission of a paper for publication is that authors declare explicitly that their work is original and has not appeared in a publication elsewhere. Re-use of any data should be appropriately cited. As such this article represents a severe abuse of the scientific publishing system. The scientific community takes a very strong view on this matter and apologies are offered to readers of the journal that this was not detected during the submission process.
显示更多 [+] 显示较少 [-]Uptake of nicotine from discarded cigarette butts – A so far unconsidered path of contamination of plant-derived commodities
2018
Selmar, Dirk | Radwan, Alzahraa | Abdalla, Neama | Taha, Hussein | Wittke, Carina | El-Henawy, Ahmed | Alshaal, Tarek | Amer, Megahed | Kleinwächter, Maik | Nowak, Melanie | El-Ramady, Hassan
This study aimed to elucidate the origin of the widespread nicotine contamination of plant-derived commodities, by conducting field experiments with various herbs and spice plants. By scattering tobacco and cigarette butts on the field and subsequent nicotine analyses of the acceptor plants, we verified that the alkaloid is leached out into the soil and is taken up by the crop plants. This path of contamination pertains even when there is only one cigarette butt per square meter. Even such minor pollution results - at least in the case of basil and peppermint - in considerable high nicotine contaminations, which exceed the maximum residue level by more than 20-fold.The data reported here clearly outline the large practical relevance of this soil-borne contamination path and imply that unthoughtful disposal of cigarette butts in the field by farm workers may be the reason for the widespread occurrence of nicotine contamination in plant-derived commodities. Therefore, such misbehavior needs to be prevented using education and sensitization, and by including this issue into the guidelines of good agricultural practice.
显示更多 [+] 显示较少 [-]Ambient fine particulate pollution associated with diabetes mellitus among the elderly aged 50 years and older in China
2018
Yang, Yin | Guo, Yanfei | Qian, Zhengmin (Min) | Ruan, Zengliang | Zheng, Yang | Woodward, Alistair | Ai, Siqi | Howard, Steven W. | Vaughn, Michael G. | Ma, Wenjun | Wu, Fan | Lin, Hualiang
The linkage between ambient air pollution exposure and occurrence of diabetes mellitus is not well defined. This study examined the association between exposure to fine particles (PM₂.₅) and the prevalence of diabetes among Chinese elderly people. We surveyed 11,504 adults aged ≥50 years in China, estimated the annual concentrations of ambient PM₂.₅ using a satellite-based model of aerosol optical depth information. We employed a generalized mixed effects model to examine the association between PM₂.₅ and the prevalence of diabetes and explored potential effect modifiers. We estimated diabetes burden attributable to ambient PM₂.₅ if the observed association is indeed causal. The diabetes prevalence among the participants was 6.5% (n = 745). Our analysis found a statistically significant association between PM₂.₅ and diabetes. The adjusted odds ratio was 1.27 (95% confidence interval (CI), 1.12, 1.43) for each 10 μg/m³ increment in ambient PM₂.₅. Stratified analyses found a lower association among the participants with higher consumption of fruit. We estimated that 22.02% (95% CI: 8.59%, 43.29%) of the diabetes cases could be ascribable to ambient PM₂.₅. Our finding suggests that PM₂.₅ exposures could increase the risk of diabetes, and if causal, could be responsible for substantial burden of diabetes among the Chinese elderly; and higher intakes of fruit might reduce the harmful effects of PM₂.₅, however, due to the limitation of the cross-sectional study design, more studies are warranted to confirm this observation.
显示更多 [+] 显示较少 [-]Transgenerational effects of cyanobacterial toxins on a tropical micro-crustacean Daphnia lumholtzi across three generations
2018
Dao, Thanh-Son | Vo, Thi-My-Chi | Wiegand, Claudia | Bui, Ba-Trung | Dinh, Khuong V.
Climate change and human activities induce an increased frequency and intensity of cyanobacterial blooms which could release toxins to aquatic ecosystems. Zooplankton communities belong to the first affected organisms, but in tropical freshwater ecosystems, this issue has yet been poorly investigated. We tested two questions (i) if the tropical Daphnia lumholtzi is capable to develop tolerance to an ecologically relevant concentration of purified microcystin-LR and microcystins from cyanobacterial extract transferable to F1 and F2 generations? And (ii) would F1 and F2 generations recover if reared in toxin-free medium? To answer these questions, we conducted two full factorial mutigenerational experiments, in which D. lumholtzi was exposed to MC-LR and cyanobacterial extract at the concentration of 1 μg L⁻¹ microcystin continuously for three generations. After each generation, each treatment was spit into two: one reared in the control (toxin free) while the other continued in the respective exposure. Fitness-related traits including survival, maturity age, body length, and fecundity of each D. lumholtzi generation were quantified. Though there were only some weak negative effects of the toxins on the first generation (F0), we found strong direct, accumulated and carried-over impacts of the toxins on life history traits of D. lumholtzi on the F1 and F2, including reductions of survival, and reproduction. The maturity age and body length showed some inconsistent patterns between generations and need further investigations. The survival, maturity age (for extract), and body length (for MC-LR) were only recovered when offspring from toxin exposed mothers were raised in clean medium for two generations. Chronic exposure to long lasting blooms, even at low density, evidently reduces survival of D. lumholtzi in tropical lakes and reservoirs with ecological consequences.
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