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Bifenthrin impairs the functions of Leydig and Sertoli cells in mice via mitochondrion-endoplasmic reticulum dysregulation 全文
2020
Ham, Jiyeon | You, Seungkwon | Lim, Whasun | Song, Gwonhwa
Bifenthrin (BF) is a synthetic insecticide that is widely used in fields, resulting in an increase in its exposure to animals. However, reports on the toxic effects of BF on mammalian species and the underlying mechanism are still lacking. Here, we elucidated the mechanism underlying the toxic effects of BF on mouse reproduction using cell lines of immature mouse Leydig (TM3) and Sertoli (TM4) cells, which are constituent cells of testes. Our results show that BF suppressed the proliferation and viability of TM3 and TM4 cells. Additionally, treatment with BF induced cell cycle arrest, apoptotic cell death, and DNA fragmentation. Mitochondrial dysfunction and disruption of calcium homeostasis were observed in BF-treated TM3 and TM4 cells. Further, bifenthrin modulated unfolded protein response and mitochondrion-associated membrane and mitogen-activated protein kinase (MAPK)/phosphoinositide 3-kinase (PI3K) signaling pathways. The expression of the mRNAs related to cell cycle progression, steroidogenesis, and spermatogenesis was downregulated by BF, suggestive of testicular toxicity. Taken together, these results demonstrate the intracellular mechanism of action of BF to involve antiproliferative and apoptotic effects and testicular dysfunction in mouse testis.
显示更多 [+] 显示较少 [-]Mechanistic insights and multiple characterizations of cadmium binding to animal-derived biochar 全文
2020
Lei, Sicong | Zhu, Ling | Xue, Cong | Hong, Chengyi | Wang, Junliang | Che, Lei | Hu, Yongfeng | Qiu, Yuping
Cattle-derived biochar (CB), which is derived from industrial pyrolysis of cattle carcasses in harmless treatment plants, is a naturally occurring mineral form of carbonate-bearing hydroxyapatite (CHAP) with a small amount of elemental carbon. CB has 4.02% of carbonate content, which falls under the B-type substitution of CHAP. In this work, the Cd(II) sorption capacity of CB was determined to be 0.82 mmol/g, with 97.6% of the Cd(II) uptake contributing to CHAP and only 2.36% of the Cd(II) uptake contributing to the elemental carbon component. The calculation and linear combination fitting (LCF) of Cd L₃-edge X-ray absorption near-edge structure (XANES) analysis indicated that the contributions of Cd(II) species to CB presented the following order: ion exchange (57.6%–61.0%) > precipitation (24.4%–29.9%) > surface complexation (12.5%–13.4%). The depth dependent X-ray photoelectron spectroscopy (XPS) showed the presence of ion exchange, which is accompanied by intraparticle diffusion. LCF of XANES and Rietveld analysis of X-ray diffraction (XRD) demonstrated that Cd(II) was precipitated in the form of Cd₅H₂(PO₄)₄·4H₂O on the CB surface. Furthermore, the precipitate was directly observed and identified by scanning electron microscopy with energy-dispersive spectroscopy (SEM-EDS). Consequently, we revealed the intricate binding mechanism of Cd(II) to CHAP-rich CB and confirmed the importance of surface precipitation.
显示更多 [+] 显示较少 [-]Investigating arsenic impact of ACC treated timbers in compost production (A case study in Christchurch, New Zealand) 全文
2020
Safa, Majeed | O’Carroll, Daniel | Mansouri, Nazanin | Robinson, Brett | Curline, Greg
The arsenic concentration is an important issue in compost production. The main inputs of a compost factory, including kerbsides, green wastes, food industry wastes, and river weeds are investigated in this study. Also, this study investigated how treated timbers, ashes, and other contamination can impact arsenic concentration in compost production. The results showed that most treated timbers and all ashes of treated and untreated timbers contained significant amounts of arsenic. These results revealed that the presence of a small amount of treated timber ashes can significantly increase the arsenic concentration in composts. The results of the study show the arsenic concentration in compost increase during cold months, and it dropped during summer, which would be mostly because of high arsenic concentration in ashes of log burners. This study shows ashes of burning timbers can impact arsenic contamination mostly because of using Copper-Chrome-Arsenic wood preservatives (CCA). Also, the lab results show the arsenic level even in ashes of untreated timber is around 96 ppm. The ashes of H3, H4, and H5 treated timbers contain approximately 133,000, 155,000, and 179,000 ppm of arsenic, which one kg of them can increase arsenic concentration around 10 ppm in 13.3, 15.5 and 17.9 tons of dry compost products. The main problem is many people look at ashes and treated timber as organic materials; however, ashes of treated and untreated timbers contained high concentrations of arsenic. Therefore, it was necessary to warn people about the dangers of putting any ashes in organic waste bins.
显示更多 [+] 显示较少 [-]The imidacloprid remediation, soil fertility enhancement and microbial community change in soil by Rhodopseudomonas capsulata using effluent as carbon source 全文
2020
Wu, Pan | Zhang, Xuewei | Niu, Tong | Wang, Yanling | Liu, Rijia | Zhang, Ying
The effects of Rhodopseudomonas capsulata (R. capsulata) in the treated effluent of soybean processing wastewater (SPW) on the remediation of imidacloprid in soil, soil fertility, and the microbial community structure in soil were studied. Compared with the control group, with the addition of effluent containing R. capsulata, imidacloprid was effectively removed, soil fertility was enhanced, and the microbial community structure was improved. Molecular analysis indicated that imidacloprid could exert induction effects on expression of cpm gene and regulation effects on the synthesis of cytochrome P450 monooxygenases (P450) by activating HKs gene in two-component system (TCS). For R. capsulata, this induction process required 1 day. The synthesis of P450 occurred 1 day after inoculation, because R. capsulata are a type of archaea and imidacloprid is an environmental stress. Before expression of the cpm gene and synthesis of P450, R. capsulata need a period of time to adapt to external imidacloprid stimulation. However, the lack of organic matter in the soil cannot sustain R. capsulata growth for more than 1 day. In four groups with added effluent, the remaining organic matter in the effluent provided a sufficient carbon source and energy for R. capsulata. Five days later, the microbial community structure was improved by R. capsulata in the soil. The new technique could be used to remediate imidacloprid, enhance soil fertility, treat SPW and realize the recycling and reuse of wastewater and R. capsulata cells.
显示更多 [+] 显示较少 [-]Genome-wide DNA methylation analysis reveals significant impact of long-term ambient air pollution exposure on biological functions related to mitochondria and immune response 全文
2020
Wang, Maiqiu | Zhao, Junsheng | Wang, Yan | Mao, Ying | Chao, Shin-Yi | Huang, Peng | Liu, Qiang | Ma, Yunlong | Yao, Yinghao | Yang, Zhongli | Yuan, Wenji | Cui, Wenyan | Payne, Thomas J. | Li, Ming D.
Exposure to long-term ambient air pollution is believed to have adverse effects on human health. However, the mechanisms underlying these impacts are poorly understood. DNA methylation, a crucial epigenetic modification, is susceptible to environmental factors and likely involved in these processes. We conducted a whole-genome bisulfite sequencing study on 120 participants from a highly polluted region (HPR) and a less polluted region (LPR) in China, where the HPR had much higher concentrations of five air pollutants (PM₂.₅, PM₁₀, SO₂, NO₂, and CO) (fold difference 1.6 to 6.6 times; P value 1.80E-07 to 3.19E-23). Genome-wide methylation analysis revealed 371 DMRs in subjects from the two areas and these DMRs were located primarily in gene regulatory elements such as promoters and enhancers. Gene enrichment analysis showed that DMR-related genes were significantly enriched in diseases related to pulmonary disorders and cancers and in biological processes related to mitochondrial assembly and cytokine production. Further, HPR participants showed a higher mtDNA copy number. Of those identified DMRs, 15 were significantly correlated with mtDNA copy number. Finally, cytokine assay indicated that an increased plasma interleukin-5 level was associated with greater air pollution. Taken together, our findings suggest that exposure to long-term ambient air pollution can lead to alterations in DNA methylation whose functions relate to mitochondria and immune responses.
显示更多 [+] 显示较少 [-]Microplastics combined with tetracycline in soils facilitate the formation of antibiotic resistance in the Enchytraeus crypticus microbiome 全文
2020
Ma, Jun | Sheng, G Daniel | O’Connor, Patrick
Growing evidence suggests that microplastics can adsorb antibiotics and may consequently exacerbate effects on the health of exposed organisms. Our current understanding of the combined effects of microplastics and antibiotics on antibiotic resistance genes (ARGs) in soil invertebrates is limited. This study aimed to investigate changes in the microbiome and ARGs in Enchytraeus crypticus following exposure to a soil environment that contained both microplastics and antibiotics. Tetracycline (TC), polyamide (PA) and polyvinyl chloride (PVC) were used to construct microcosms of polluted soil environments (TC, PA, PVC, PA+TC, PVC+TC). The differences in microbiomes and ARGs were determined by bacterial 16S rRNA gene amplicon sequencing and high throughput quantitative PCR. The results show that compared with the Control or microplastics alone treatments, TC was significantly accumulated in E. crypticus when exposed to TC alone or in combination with microplastics (P < 0.05), but there were no significant differences about TC accumulation between TC, PA+TC, and PVC+TC treated E. crypticus (P > 0.05). Microplastics and TC significantly disturbed the microbial community, and decreased the microbial alpha diversity of E. crypticus (P < 0.05). However, there were no significant differences between TC, microplastics and their combined exposure treatments, and no toxic synergies on the diversity of E. crypticus microbiome between tetracycline and microplastics in soil environment. All the treatments increased the diversity of ARGs in E. crypticus (39–49 ARGs vs. 25 ARGs of control). In particular, treatments combining PVC and TC or PA and TC exposure resulted in greater ARGs abundance than the treatments when E. crypticus was exposed to PVC, PA or TC alone. These results add to our understanding of the combined effects of microplastics and antibiotics on the ARGs and microbiome of soil invertebrates.
显示更多 [+] 显示较少 [-]Waterborne protozoan pathogens in environmental aquatic biofilms: Implications for water quality assessment strategies 全文
2020
Masangkay, Frederick R. | Milanez, Giovanni D. | Tsiami, Amalia | Hapan, Freida Z. | Somsak, Voravuth | Kotepui, Manas | Tangpong, Jitbanjong | Karanis, Panagiotis
Biofilms containing pathogenic organisms from the water supply are a potential source of protozoan parasite outbreaks and a significant public health concern. The aim of the present study was to demonstrate the simultaneous and multi-spatial occurrence of waterborne protozoan pathogens (WBPP) in substrate-associated biofilms (SAB) and compare it to surface water (SW) and sediments with bottom water (BW) counterparts using manual filtration and elution from low-volume samples. For scenario purposes, simulated environmental biofilm contamination was created from in-situ grown one-month-old SAB (OM-SAB) that were spiked with Cryptosporidium parvum oocysts. Samples were collected from the largest freshwater reservoirs in Luzon, Philippines and a University Lake in Thailand. A total of 69 samples (23 SAB, 23 SW, and 23 BW) were evaluated using traditional staining techniques for Cryptosporidium, and Immunofluorescence staining for the simultaneous detection of Cryptosporidium and Giardia. WBPP were found in 43% SAB, 39% SW, and 39% BW of the samples tested in the present study with SAB results reflecting SW and BW results. Further highlights were demonstrated in the potential of using low-volume samples for the detection of parasites in source water. Scanning electron microscopy of OM-SAB samples revealed a naturally-associated testate amoeba shell, while Cryptosporidium oocysts spiked samples provided a visual profile of what can be expected from naturally contaminated biofilms. This study provides the first evidence for the simultaneous and multi-spatial occurrence of waterborne protozoan pathogens in low-volume aquatic matrices and further warrants SAB testing along with SW and BW matrices for improved water quality assessment strategies (iWQAS).
显示更多 [+] 显示较少 [-]Distinct microbial communities and their networks in an anammox coupled with sulfur autotrophic/mixotrophic denitrification system 全文
2020
Du, Shuai | Ya, Tao | Zhang, Minglu | Zhu, Minghan | Li, Nankun | Liu, Shuwei | Wang, Xiaohui
Organ carbon are often used to enhance denitrification in wastewater treatment. However, their possible effects on microbial interactions are very limited. In this work, an anaerobic ammonium oxidation (anammox) coupled with sulfur autotrophic/mixotrophic denitrification (SAD/SMD) system was used to investigate the changes in microbial interactions among the microbial communities under different nutrient condition. The removal efficiency of total nitrogen increased from 70% (SAD) to 97% (SMD). The Illumina sequencing analysis indicated that Planctomycetes was the most dominant bacterial phylum in anammox system. Thiobacillus and Sulfurimonas, two typical autotrophic denitrifiers, decreased significantly from 31.9% to 17.7%–12.2% and 9.3%, when the nutrient condition changed from SAD to SMD (P < 0.05). Meanwhile, some heterotrophic or mixotrophic denitrifying bacteria, including Gemmobacter, Pseudomonas and Thauera increased significantly (P < 0.05). Molecular ecological network (MEN) analysis showed that the addition of organic carbon substantially altered the overall architecture of the network. Compared with SAD, the SMD had shorter path lengths, indicating higher transfer efficiencies of information and materials among different microorganism. The addition of organic carbon increased the microbial interaction complexity of Proteobacteria. The links of Thiobacillus, which was a typical sulfur-oxidizing autotrophic denitrifying bacteria, significantly reduced (P < 0.05) with the addition of organic carbon, while the links of the heterotrophic bacteria Geobacter significantly increased (P < 0.05). This study provided new insights into our understanding of the shifts in the bacteria community and their microbial interactions under different nutrient conditions (SAD and SMD) in sulfur-supported denitrification system.
显示更多 [+] 显示较少 [-]Ecological risk of human health in sediments in a karstic river basin with high longevity population 全文
2020
Deng, Qucheng | Wei, Yongping | Yin, Juan | Chen, Lijuan | Peng, Chong | Wang, Xiaofei | Zhu, Kaixian
Health and longevity are common human goals, and environmental factors can have significant impacts on human health. This study aims to investigate the historical changes and sources of trace elements in the sediments of a typical karstic river basin with high longevity population in Hechi City, Guangxi, China and to evaluate the ecological risks of trace elements in sediments. The results showed that over the past 100 years, the contents of trace elements in the sediments were lower in the upper reaches than in the middle and lower reaches of the river. The sediments had high trace element contents in 1950–1959 and 1989–1998, while low contents appeared after 1998. These periods correspond to China’s industrial growth in the early 1950s, the Great Leap Forward movement in the late 1950s, the reform and opening-up policy implemented in the 1980s–1990s and the environmental protection policies to strengthen pollution control that have been implemented since 2000. Limestone soil and carbonate rock are the main sources of sediment in the basin. Although the geological background values of Cd and other trace elements in the basin were relatively high, the high calcium content and alkalinity of the water and sediment in the basin reduced the bioavailability of Cd and other heavy metals. The mainstream of Panyang River had a low environmental risk, but the tributary Bama River where there is dense population poses a moderate risk.
显示更多 [+] 显示较少 [-]Distribution and ecological risk of substituted and parent polycyclic aromatic hydrocarbons in surface waters of the Bai, Chao, and Chaobai rivers in northern China 全文
2020
Like their parent polycyclic aromatic hydrocarbons (PAHs), substituted polycyclic aromatic hydrocarbons (SPAHs), including methyl PAHs (MPAHs), oxygenated PAHs (OPAHs), and chlorinated PAHs (ClPAHs), exist ubiquitously in urban and agricultural rivers. Although laboratory studies have found the biological toxicities of certain SPAHs to be higher than that of their parent PAHs, the ecological risk of SPAHs in rivers has been largely ignored. Here, we studied the distribution, source and transport of PAHs and SPAHs as well as ecological risks in the Chaobai River System, which experiences a high level of anthropogenic activity. The results show that the concentration of ΣOPAHs (321 ± 651 ng/L) was higher than that of ΣPAHs (158 ± 105 ng/L), ΣMPAHs (28 ± 22 ng/L), and ΣClPAHs (30 ± 12 ng/L). We also found that (S)PAHs in Chaobai River mainly originated from Beiyun River (53%–65%), which receives considerable municipal wastewater treatment plant effluent from Beijing. The major transport pathway of (S)PAHs from Chaobai River was likely for irrigation (83%–86%) and transportation into Yongdingxin River (13%–16%), which finally merged into the Bohai Sea. The mixed chronic risk of (S)PAHs (risk quotient = 45 ± 53) was higher than the mixed acute risk (risk quotient = 1.9 ± 1.4), with all sites facing chronic risk and 90% of sites experiencing acute risk. Although the chronic and acute risks of (S)PAHs to plants, invertebrates, and vertebrates were mainly from PAHs (97.5% to chronic risk and 96.5% to acute), SPAHs still posed a chronic risk to invertebrates and vertebrates (risk quotient > 1). Accordingly, the ecological risk of (S)PAHs in Chaobai River should be taken into consideration for ecosystem protection. The transmission of PAHs and SPAHs from Chaobai River may also pose potential risks to farmland through irrigation, as well as to the Bohai Sea via river water discharge.
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