Publications by authors named "Tiecheng Wang"

122 Publications

Plasma induced efficient removal of antibiotic-resistant Escherichia coli and antibiotic resistance genes, and inhibition of gene transfer by conjugation.

J Hazard Mater 2021 Jun 24;419:126465. Epub 2021 Jun 24.

College of Natural Resources and Environment, Northwest A&F University, Yangling, Shaanxi Province 712100, China; Key Laboratory of Plant Nutrition and the Agri-environment in Northwest China, Ministry of Agriculture, Yangling, Shaanxi 712100, China. Electronic address:

Antibiotic-resistant bacteria (ARB) and their resistance genes (ARGs) are emerging environmental pollutants that pose great threats to human health. In this study, a novel strategy using plasma was developed to simultaneously remove antibiotic-resistant Escherichia coli (AR bio-56954 E. coli) and its ARGs, aiming to inhibit gene transfer by conjugation. Approximately 6.6 log AR bio-56954 E. coli was inactivated within 10 min plasma treatment, and the antibiotic resistance to tested antibiotics (tetracycline, gentamicin, and amoxicillin) significantly decreased. Reactive oxygen and nitrogen species (RONS) including •OH, O, O•, NO, and NO contributed to ARB and ARGs elimination; their attacks led to destruction of cell membrane, accumulation of excessive intracellular reactive oxygen substances, deterioration of conformational structures of proteins, and destroy of nucleotide bases of DNA. As a result, the ARGs (tet(C), tet(W), blaTEM-1, aac(3)-II), and integron gene intI1), and conjugative transfer frequency of ARGs significantly decreased after plasma treatment. The results demonstrated that plasma has great prospective application in removing ARB and ARGs in water, inhibiting gene transfer by conjugation.
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http://dx.doi.org/10.1016/j.jhazmat.2021.126465DOI Listing
June 2021

Characteristics of Chimeric West Nile Virus Based on the Japanese Encephalitis Virus SA14-14-2 Backbone.

Viruses 2021 Jun 29;13(7). Epub 2021 Jun 29.

Key Laboratory of Jilin Province for Zoonosis Prevention and Control, Changchun Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Changchun 130122, China.

West Nile virus disease (WND) is an arthropod-borne zoonosis responsible for nonspecific fever or severe encephalitis. The pathogen is West Nile virus belonging to the genus family . Every year, thousands of cases were reported, which poses significant public health risk. Here, we constructed a West Nile virus chimera, ChiVax-WN01, by replacing the gene of JEV SA14-14-2 with that of the West Nile virus NY99. The ChiVax-WN01 chimera showed clear, different characters compared with that of JEV SA14-14-2 and WNV NY99 strain. An animal study indicated that the ChiVax-WN01 chimera presented moderate safety and immunogenicity for 4-week female BALB/c mice.
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http://dx.doi.org/10.3390/v13071262DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8309971PMC
June 2021

SARS-CoV-2 Aerosol Exhaled by Experimentally Infected Cynomolgus Monkeys.

Emerg Infect Dis 2021 07;27(7):1979-1981

We analyzed size of severe acute respiratory coronavirus 2 (SARS-CoV-2) aerosol particles shed by experimentally infected cynomolgus monkeys. Most exhaled particles were small, and virus was mainly released early during infection. By postinfection day 6, no virus was detected in breath, but air in the isolator contained large quantities of aerosolized virus.
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http://dx.doi.org/10.3201/eid2707.203948DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8237865PMC
July 2021

The Application of a Safe Neutralization Assay for Ebola Virus Using Lentivirus-Based Pseudotyped Virus.

Virol Sin 2021 Jun 21. Epub 2021 Jun 21.

Key Laboratory of Zoonosis Research, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, 130062, China.

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http://dx.doi.org/10.1007/s12250-021-00405-8DOI Listing
June 2021

Viral and host transcriptomes in SARS-CoV-2 infected human lung cells.

J Virol 2021 Jun 9:JVI0060021. Epub 2021 Jun 9.

Institute of Military Veterinary Medicine, Academy of Military Medical Sciences, Changchun, 130122, P. R. China.

Coronaviruses are commonly characterized by a unique discontinuous RNA transcriptional synthesis strategy guided by transcription-regulating sequences (TRSs). However, the details of RNA synthesis in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have not been fully elucidated. Here, we present a time-scaled, gene-comparable transcriptome of SARS-CoV-2, demonstrating that ACGAAC functions as a core TRS guiding the discontinuous RNA synthesis of SARS-CoV-2 from a holistic perspective. During infection, viral transcription, rather than genome replication, dominates all viral RNA synthesis activities. The most highly expressed viral gene is the nucleocapsid gene, followed by ORF7 and ORF3 genes, while the envelope gene shows the lowest expression. Host transcription dysregulation keeps exacerbating after viral RNA synthesis achieves to the top. The most enriched host pathways are metabolism-related. Two of them (cholesterol and valine metabolism) affect viral replication in reverse. Furthermore, the activation of numerous cytokines emerges before the large-scale viral RNA synthesis. SARS-CoV-2 is responsible for the current severe global health emergency that began at the end of 2019. Although the universal transcriptional strategies of coronaviruses are preliminarily understood, the details of RNA synthesis, especially the time-matched transcription level of each SARS-CoV-2 gene and the principles of subgenomic mRNA synthesis, are not clear. The coterminal subgenomic mRNAs of SARS-CoV-2 present obstacles in identifying the expression of most genes by PCR-based methods, which is exacerbated by the lack of related antibodies. Moreover, SARS-CoV-2-related metabolic imbalance and cytokine storm are receiving increasing attention from both clinical and mechanistic perspectives. Our transcriptomic research provides information on both viral RNA synthesis and host responses, in which the transcription-regulating sequences and transcription levels of viral genes are demonstrated, and the metabolic dysregulation and cytokine levels identified at the host cellular level support the development of novel medical treatment strategies.
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http://dx.doi.org/10.1128/JVI.00600-21DOI Listing
June 2021

Estrogen/ER in anti-tumor immunity regulation to tumor cell and tumor microenvironment.

Cancer Cell Int 2021 Jun 7;21(1):295. Epub 2021 Jun 7.

Department of Orthopedics, 2nd Affiliated Hospital, School of Medicine, Zhejiang University, #88 Jiefang Road, Hangzhou, 310009, Zhejiang, People's Republic of China.

As the essential sexual hormone, estrogen and its receptor has been proved to participate in the regulation of autoimmunity diseases and anti-tumor immunity. The adjustment of tumor immunity is related to the interaction between cancer cells, immune cells and tumor microenvironment, all of which is considered as the potential target in estrogen-induced immune system regulation. However, the specific mechanism of estrogen-induced immunity is poorly understood. Typically, estrogen causes the nuclear localization of estrogen/estrogen receptor complex and alternates the transcription pattern of target genes, leading to the reprogramming of tumor cells and differentiation of immune cells. However, the estrogen-induced non-canonical signal pathway activation is also crucial to the rapid function of estrogen, such as NF-κB, MAPK-ERK, and β-catenin pathway activation, which has not been totally illuminated. So, the investigation of estrogen modulatory mechanisms in these two manners is vital for the tumor immunity and can provide the potential for endocrine hormone targeted cancer immunotherapy. Here, this review summarized the estrogen-induced canonical and non-canonical signal transduction pathway and aimed to focus on the relationship among estrogen and cancer immunity as well as immune-related tumor microenvironment regulation. Results from these preclinical researches elucidated that the estrogen-target therapy has the application prospect of cancer immunotherapy, which requires the further translational research of these treatment strategies.
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http://dx.doi.org/10.1186/s12935-021-02003-wDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8182917PMC
June 2021

An inactivated recombinant rabies virus displaying the Zika virus prM-E induces protective immunity against both pathogens.

PLoS Negl Trop Dis 2021 Jun 4;15(6):e0009484. Epub 2021 Jun 4.

Key Laboratory of Zoonosis Research, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, China.

The global spread of Zika virus (ZIKV), which caused a pandemic associated with Congenital Zika Syndrome and neuropathology in newborns and adults, prompted the pursuit of a safe and effective vaccine. Here, three kinds of recombinant rabies virus (RABV) encoding the prM-E protein of ZIKV were constructed: ZI-D (prM-E), ZI-E (transmembrane domain (TM) of prM-E replaced with RABV G) and ZI-F (signal peptide and TM domain of prM-E replaced with the region of RABV G). When the TM of prM-E was replaced with the region of RABV G (termed ZI-E), it promoted ZIKV E protein localization on the cell membrane and assembly on recombinant viruses. In addition, the change in the signal peptide with RABV G (termed ZI-F) was not conducive to foreign protein expression. The immunogenicity of recombinant viruses mixed with a complex adjuvant of ISA 201 VG and poly(I:C) was tested in BALB/c mice. After immunization with ZI-E, the anti-ZIKV IgG antibody lasted for at least 10 weeks. The titers of neutralizing antibodies (NAbs) against ZIKV and RABV at week 6 were all greater than the protective titers. Moreover, ZI-E stimulated the proliferation of splenic lymphocytes and promoted the secretion of cytokines. It also promoted the production of central memory T cells (TCMs) among CD4+/CD8+ T cells and stimulated B cell activation and maturation. These results indicate that ZI-E could induce ZIKV-specific humoral and cellular immune responses, which have the potential to be developed into a promising vaccine for protection against both ZIKV and RABV infections.
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http://dx.doi.org/10.1371/journal.pntd.0009484DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8208564PMC
June 2021

Development of recombinase polymerase amplification assays for rapid and visual detection of canine distemper virus infecting giant panda.

BMC Vet Res 2021 Apr 23;17(1):172. Epub 2021 Apr 23.

Key Laboratory of Jilin Province for Zoonosis Prevention and Control, Institute of Military Veterinary, Academy of Military Medical Sciences, Changchun, China.

Background: Canine distemper virus (CDV) is an enveloped negative-strand RNA virus that exhibits a high mutation rate and continuously expands the range of hosts. Notably, CDV has infected giant panda with spill over from viral reservoirs in canines. Giant pandas (Ailuropoda melanoleuca), especially captive pandas, are known to be susceptible to natural infection with CDV. The high fatality rate of CDV poses a serious threat to the safety of the giant panda population. However, vaccines or drugs for canine distemper in giant pandas have not been developed to date. Therefore, a rapid test that can achieve accurate onsite detection of CDV is important to enable the timely implementation of control measures. In this study, we established a nucleic acid visualization assay for targeting the CDV N gene by using combines reverse transcription recombinase polymerase amplification with a closed vertical flow visualization strip (RT-RPA-VF).

Results: The RT-RPA-VF assay does not require sophisticated equipment, and it was determined to provide rapid detection at 35 °C for 30 min, while the limit of detection was 5 × 10 copies/μl RNA transcripts and 10 TCID ml viruses. The results showed that the assay was high specific to CDV and had no cross-reactivity with other viruses infecting the giant panda. Compared with RT-qPCR, RT-RPA-VF assay had a sensitivity of 100% and a specificity of 100% in 29 clinical samples. The coincidence rate between RT-RPA-VF and RT-qPCR was 100% (kappa = 1), indicating that the RT-RPA-VF assay possessed good diagnostic performance on clinical samples.

Conclusions: The RT-RPA-VF provides a novel alternative for the simple, sensitive, and specific identification of CDV and showed great potential for point of care diagnostics for captive and wild giant panda.
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http://dx.doi.org/10.1186/s12917-021-02880-3DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8063184PMC
April 2021

PB1 S524G mutation of wild bird-origin H3N8 influenza A virus enhances virulence and fitness for transmission in mammals.

Emerg Microbes Infect 2021 Dec;10(1):1038-1051

Key Laboratory of Jilin Province for Zoonosis Prevention and Control, Institute of Military Veterinary Medicine, Academy of Military Medical Sciences, Changchun, People's Republic of China.

Influenza H3N8 viruses have been recovered frequently from wild bird species, including Anseriformes (primarily from migratory ducks) and Charadriiformes (primarily from shorebirds). However, little attention has been given to the transmission ability of H3N8 avian influenza viruses among mammals. Here, we study the potential human health threat and the molecular basis of mammalian transmissibility of H3N8 avian influenza viruses isolated from wild bird reservoirs. We classified eight H3N8 viruses into seven different genotypes based on genomic diversity. Six of eight H3N8 viruses isolated naturally from wild birds have acquired the ability to bind to the human-type receptor. However, the affinity for α-2,6-linked SAs was lower than that for α-2,3-linked SAs. Experiments on guinea pigs demonstrated that three viruses transmitted efficiently to direct-contact guinea pigs without prior adaptation. Notably, one virus transmitted efficiently via respiratory droplets in guinea pigs but not in ferrets. We further found that the PB1 S524G mutation conferred T222 virus airborne transmissibility between ferrets. We also determined that the 524G mutant increased viral pathogenicity slightly in mice compared with the WT (wild type). Based on these results, we elucidated the potential human health threat and molecular basis of mammalian transmissibility of H3N8 influenza viruses. We emphasized the need for continued surveillance of the H3N8 influenza viruses circulating in birds.
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http://dx.doi.org/10.1080/22221751.2021.1912644DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8183522PMC
December 2021

Low Expression Indicates a Biomarker of Poor Prognosis in Patients with Renal Cell Carcinoma.

Biomed Res Int 2021 24;2021:6682758. Epub 2021 Mar 24.

Key Laboratory of JiLin Province for Zoonosis Prevention and Control, Institute of Military Veterinary Medicine, Academy of Military Medical Sciences, Changchun 130122, China.

It was initially found that neural-restrictive silencer factor/repressor 1-silencing transcription factor () is a transcriptional repressor of neuronal genes in nonneuronal cells. However, it is reported to be abundantly expressed in various types of aggressive cancer cells. In this study, we evaluated the expression patterns of in renal cell carcinoma and found that its expression is lower in tumor tissues compared to normal tissues. The chi-square test showed that the low expression was closely related to patients' clinicopathologic parameters, including the pathologic stage and survival status. ROC curve showed that had excellent clinical diagnostic prospect. In addition, patients with low expression had poor over survival (OS) and relapse-free survival (RFS). Univariate and multivariate Cox regression analysis confirmed that the low expression was an independent predictor of poor prognosis in renal cell carcinoma. Gene set enrichment analysis identified P53 pathway, reactive oxygen species pathway, glycolysis, DNA repair, cholesterol homeostasis, and MYC targets V2 enriched with low expression phenotype. These results suggested that may be a novel biomarker for the diagnosis and prognosis of renal cell carcinoma in clinical applications.
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http://dx.doi.org/10.1155/2021/6682758DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8012131PMC
May 2021

Insights into the underlying mechanisms for integrated inactivation of A. spiroides and depression of disinfection byproducts by plasma oxidation.

Water Res 2021 May 9;196:117027. Epub 2021 Mar 9.

College of Natural Resources and Environment, Northwest A&F University, Yangling, Shaanxi 712100, PR China; Key Laboratory of Plant Nutrition and the Agri-environment in Northwest China, Ministry of Agriculture, Yangling, Shaanxi 712100, PR China. Electronic address:

Cyanobacteria blooms threaten water supply and are potential sources for disinfection byproducts (DBPs) formation. In this study, the underlying mechanisms for effective removal of A. spiroides and the following depression on the formation of DBPs were disclosed. Highly efficient inactivation (more than 99.99%) of A. spiroides was realized by the plasma treatment within 12 min, and 93.4% of Anatoxin-a was also removed within 12 min, with no signals of resurrection after 7 days' re-cultivation. Transcriptomic analysis demonstrated that the expressions of the genes related to cell walls and peripherals, thylakoid membranes, photosynthetic membranes, and detoxification of toxins were distinctly altered. The generated reactive oxidative species (ROS), including ·OH, O, and O, attacked A. spiroides and resulted in membrane damage and algae organic matter (AOM) release. EEM-PARAFAC analysis illustrated that the AOM compositions were subsequently decomposed by the ROS. As a result, the formation potentials of the C-DBPs and N-DBPs were significantly inhibited, due to the effectively removal of AOM and Anatoxin-a. This study disclosed the underneath mechanisms for the effective inactivation of A. spiroides and inhibition of the following formation of the DBPs, and supplied a prospective technique for integrated pollutant control of cyanobacterial containing drinking water.
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http://dx.doi.org/10.1016/j.watres.2021.117027DOI Listing
May 2021

Nucleic acid visualization assay for Middle East Respiratory Syndrome Coronavirus (MERS-CoV) by targeting the UpE and N gene.

PLoS Negl Trop Dis 2021 03 1;15(3):e0009227. Epub 2021 Mar 1.

Key Laboratory of Zoonosis Research, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, China.

Since its first emergence in 2012, cases of infection with Middle East respiratory syndrome coronavirus (MERS-CoV) have continued to occur. At the end of January 2020, 2519 laboratory confirmed cases with a case-fatality rate of 34.3% have been reported. Approximately 84% of human cases have been reported in the tropical region of Saudi Arabia. The emergence of MERS-CoV has highlighted need for a rapid and accurate assay to triage patients with a suspected infection in a timely manner because of the lack of an approved vaccine or an effective treatment for MERS-CoV to prevent and control potential outbreaks. In this study, we present two rapid and visual nucleic acid assays that target the MERS-CoV UpE and N genes as a panel that combines reverse transcription recombinase polymerase amplification with a closed vertical flow visualization strip (RT-RPA-VF). This test panel was designed to improve the diagnostic accuracy through dual-target screening after referencing laboratory testing guidance for MERS-CoV. The limit of detection was 1.2×101 copies/μl viral RNA for the UpE assay and 1.2 copies/μl viral RNA for the N assay, with almost consistent with the sensitivity of the RT-qPCR assays. The two assays exhibited no cross-reactivity with multiple CoVs, including the bat severe acute respiratory syndrome related coronavirus (SARSr-CoV), the bat coronavirus HKU4, and the human coronaviruses 229E, OC43, HKU1 and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Furthermore, the panel does not require sophisticated equipment and provides rapid detection within 30 min. This panel displays good sensitivity and specificity and may be useful to rapidly detect MERS-CoV early during an outbreak and for disease surveillance.
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http://dx.doi.org/10.1371/journal.pntd.0009227DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7951983PMC
March 2021

Excess sludge disintegration by discharge plasma oxidation: Efficiency and underlying mechanisms.

Sci Total Environ 2021 Jun 7;774:145127. Epub 2021 Feb 7.

College of Natural Resources and Environment, Northwest A&F University, Yangling, Shaanxi Province 712100, PR China; Key Laboratory of Plant Nutrition and the Agri-environment in Northwest China, Ministry of Agriculture, Yangling, Shaanxi 712100, PR China. Electronic address:

A huge amount of excess sludge is inevitably produced in wastewater treatment, and it is becoming more and more urgent to realize efficient sludge reduction. Discharge plasma oxidation was used to efficiently disintegrate excess sludge for sludge reduction in this study. Approximately 18.22% sludge disintegration and 27.8% reduction of total suspended solids (TSS) were achieved by discharge plasma treatment. The water content of the filter cake decreased from 81.9% to 76.0% and the bound water content decreased from 2.66 g/g dry solid to 0.73 g/g dry solid after treatment. The large quantities of reactive oxygen species (ROS) generated by discharge plasma played important roles in sludge disintegration by destroying flocs and promoting the transformation of organic substances. Concurrent cell lysis induced by ROS oxidation released intracellular organics and water into the liquid phase. The fraction of soluble extracellular polymer substances (S-EPS) was enhanced from 16.10% to 58.51%, whereas the tightly bound fraction was reduced from 70.62% to 28.91%. Migration and decomposition of EPS were the main processes for EPS changing at a low oxidation capacity, whereas cell lysis became important at a high oxidation capacity. In summary, the plasma treatment effectively improved sludge disintegration.
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http://dx.doi.org/10.1016/j.scitotenv.2021.145127DOI Listing
June 2021

Greatly enhanced oxidative activity of δ-MnO to degrade organic pollutants driven by dominantly exposed {-111} facets.

J Hazard Mater 2021 07 2;413:125285. Epub 2021 Feb 2.

Key Laboratory of Plant Nutrition and the Agri-environment in Northwest China, Ministry of Agriculture, College of Natural Resources and Environment, Northwest A & F University, Yangling 712100, China; Key Laboratory of Pollution Processes and Environmental Criteria, Ministry of Education, Tianjin Key Laboratory of Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai University, Tianjin 300071, China. Electronic address:

The reactivity of oxidizing materials is highly related to the exposed crystal facets. Herein, δ-MnO with different exposure facets were synthesized and the oxidative activities of the as-prepared materials were evaluated by degrading phenol in water without light. The degradation rate of phenol by δ-MnO-{-111} was significantly higher than that by δ-MnO-{001}. δ-MnO-{-111} also displayed high degradation efficiency to a variety of other organic pollutants, such as ciprofloxacin, bisphenol A, 3-chlorophenol and sulfadiazine. Comprehensive characterization and theoretical calculation verified that the {-111} facet had high density of Mn, thus displaying enhanced direct oxidative capacity to degrade organic pollutants. In addition, the dominant {-111} facet promoted adsorption/activation of O, thus favored the generation of superoxide radical (O), which actively participated in the degradation of pollutants. The phenol degradation kinetics could be divided into two distinct phases: the rapid phase (k1 = 0.468 min) induced by Mn and the slower phase (k2 = 0.048 min) dominated by O. The synergistically promoted non-radical and radical based reactions resulted in greatly enhanced the oxidative activity of the δ-MnO-{-111}. These findings deepen the understanding of facet-dependent oxidative performance of materials and provided valuable insights into the possible practical application of δ-MnO for water purification.
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http://dx.doi.org/10.1016/j.jhazmat.2021.125285DOI Listing
July 2021

H9N2 influenza virus spillover into wild birds from poultry in China bind to human-type receptors and transmit in mammals via respiratory droplets.

Transbound Emerg Dis 2021 Feb 10. Epub 2021 Feb 10.

Changchun Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Changchun, China.

H9N2 influenza virus has been reported worldwide for several decades, and it has evolved into multiple genotypes among domestic poultry. However, the study involving ecology and evolution of low pathogenic avian influenza virus H9N2 in wild birds in China is limited. Here, we carried out surveillance of avian influenza virus H9N2 in wild birds along with the East Asian-Australian migratory flyway in China in 2017. To estimate the prevalence of H9N2 avian virus in wild birds, information on exposure of wild bird populations to H9N2 viruses using serology, in addition to virology, would greatly improve monitoring capabilities. In this study, we also present serological data of H9N2 among wild birds in China during 2013-2016. We report the identification of poultry-derived H9N2 isolates from asymptomatic infected multispecies wild birds such as Common kestrel (Falco tinnunculus), Northern goshawk (Accipiter gentilis), Little owl (Athene noctua) and Ring-necked Pheasant (Phasianus colchicus) in North China in June 2017. Phylogenetic analysis demonstrated that Tianjin H9N2 isolates belong to the G81 and carry internal genes highly homologous to human H10N8 and H7N9. The isolates could directly infect mice without adaptation but were restricted to replicate in the respiratory system. Glycan-binding preference analyses suggested that the H9N2 isolates have acquired a binding affinity for the human-like receptor. Notably, results from transmission experiment in guinea pigs and ferrets demonstrated the wild birds-derived H9N2 influenza virus exhibits efficient transmission phenotypes in mammalian models via respiratory droplets. Our results indicate that the H9N2 AIVs continued to circulate extensively in wild bird populations and migratory birds play an important role in the spread and genetic diversification of H9N2 AIVs. The pandemic potential of H9N2 viruses demonstrated by aerosol transmission in mammalian models via respiratory droplets highlights the importance of monitoring influenza viruses in these hosts.
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http://dx.doi.org/10.1111/tbed.14033DOI Listing
February 2021

Enhanced removal of acid orange II from aqueous solution by V and N co-doping TiO-MWCNTs/γ-AlO composite photocatalyst induced by pulsed discharge plasma.

Water Sci Technol 2021 Jan;83(2):257-270

College of Natural Resources and Environment, Northwest A&F University, Yangling, Shaanxi, 712100, China E-mail: Key Laboratory of Plant Nutrition and the Agri-environment in Northwest China, Ministry of Agriculture, Yangling, Shaanxi, 712100, China.

This paper presents a study of V and N co-doping TiO embedding multi-walled carbon nanotubes (MWCNTs) supported on γ-AlO pellet (V/N-TiO-MWCNTs/γ-AlO) composite photocatalyst induced by pulsed discharge plasma to enhance the removal of acid orange II (AO7) from aqueous solution. The photocatalytic activity of the V/N-TiO-MWCNTs/γ-AlO composite to AO7 removal induced by the pulsed discharge plasma was evaluated. The results indicate that the V/N-TiO-MWCNTs/γ-AlO composite possesses enhanced photocatalytic activity that facilitates the removal of AO7 compared with the TiO-MWCNTs/γ-AlO and TiO/γ-AlO composites. Almost 100% of AO7 is removed after 10 min under optimal conditions. The V/N-TiO-MWCNTs/γ-AlO photocatalyst exhibits the best removal effect for AO7. Analysis of the removal mechanism indicates that the enhancement of the removal of AO7 resulting from V and N co-doping causes TiO lattice distortion and introduces a new impurity energy level, which not only reduces the band gap of TiO but also inhibits the recombination of the e/h pairs.
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http://dx.doi.org/10.2166/wst.2020.579DOI Listing
January 2021

A highly efficient recombinant canarypox virus-based vaccine against canine distemper virus constructed using the CRISPR/Cas9 gene editing method.

Vet Microbiol 2020 Dec 5;251:108920. Epub 2020 Nov 5.

College of Veterinary Medicine, Jilin Agricultural University, Changchun, 130118, China; Key Laboratory of Jilin Province for Zoonosis Prevention and Control, Institute of Military Veterinary Medicine, Academy of Military Medical Sciences, Changchun, 130122, China; Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Disease and Zoonoses, Yangzhou, 225009, China. Electronic address:

Canine distemper virus (CDV) is the causative agent of canine distemper (CD), which is one of the most important infectious diseases affecting wild and domestic carnivores. Vaccination represents an effective approach to prevent CDV infection among domestic carnivores. Canarypox-vectored recombinant CD vaccines (such as Recombitek CDV, PureVax Ferret Distemper, and Merial) with the CDV hemagglutinin (H) and fusion (F) genes can induce a potent immune response in dogs and ferrets. However, the vaccine's effectiveness varies with the species. In the current study, we developed a highly efficient recombinant canarypox virus termed as "ALVAC-CDV-M-F-H/C5" that contained CDV virus-like particles (VLPs) by using the CRISPR/Cas9 gene editing method, which enabled concurrent expression of the matrix (M), H, and F genes. The recombinant strain provided faster seroconversion than the parent strain among minks as well as provided higher rates of antibody positivity than the parent strain among foxes and minks even before the administration of a second booster vaccination. We demonstrated, for the first time, that the CRISPR/Cas9 system can be applied for the rapid and efficient modification of the ALVAC-CDV-F-H genome and also that a high-dose new recombinant strain that produces CDV VLPs may present good outcomes in the prevention of CD among foxes and minks.
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http://dx.doi.org/10.1016/j.vetmic.2020.108920DOI Listing
December 2020

First report on the sources, vertical distribution and human health risks of legacy and novel per- and polyfluoroalkyl substances in groundwater from the Loess Plateau, China.

J Hazard Mater 2021 02 29;404(Pt A):124134. Epub 2020 Sep 29.

College of Natural Resources and Environment, Northwest A&F University, Yangling, Shaanxi Province 712100, PR China; Key Laboratory of Plant Nutrition and the Agri-environment in Northwest China, Ministry of Agriculture, No.3 Taicheng Road, Yangling, Shaanxi 712100, PR China; Key Laboratory of Pollution Processes and Environmental Criteria, Ministry of Education, Tianjin Key Laboratory of Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai University, Tianjin 300071, PR China. Electronic address:

In this study, legacy and novel per and polyfluoroalkyl substances (PFASs) were measured in groundwater samples collected from the Loess Plateau of China to understand their occurrence, sources and health risks. The total concentration of PFASs ranged from 2.78 to 115 ng/L, with perfluorooctanoic acid (PFOA) as the dominant compound. Many emerging PFASs, including 6:2 fluorotelomer sulfonates (FTS), 6:2 chlorinated polyfluorinated ether sulfonic acid (Cl-PFESAs), ammonium 4,8-dioxa-3H-perfluorononanoate (ADONA), and hexafluoropropylene oxide (HFPO) homologues were frequently detected in 96.7-100% of the samples. Multiple source apportionment analyses indicated that the PFASs in the groundwater mainly originated from industrial activities, but in rural areas, agricultural activities also contributed. The total oxidizable precursor (TOP) assay indicated that there were substantial unknown precursors of perfluoroalkyl acids (PFAAs) in the groundwater samples. The total concentration of PFASs decreased with the well depth, while the PFAA-precursors displayed contrasting vertical profile trends, which might be due to the suppressed microbial transformation in the groundwater. The potential human health risk caused by PFAS exposure via drinking groundwater in the Loess Plateau was low, except for one site that was close to the industry bases.
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http://dx.doi.org/10.1016/j.jhazmat.2020.124134DOI Listing
February 2021

Enhanced cytotoxicity of photoaged phenol-formaldehyde resins microplastics: Combined effects of environmentally persistent free radicals, reactive oxygen species, and conjugated carbonyls.

Environ Int 2020 12 19;145:106137. Epub 2020 Sep 19.

Key Laboratory of Plant Nutrition and the Agri-environment in Northwest China, Ministry of Agriculture, College of Natural Resources and Environment, Northwest A & F University, Yangling 712100, China; Key Laboratory of Pollution Processes and Environmental Criteria, Ministry of Education, Tianjin Key Laboratory of Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai University, Tianjin 300071, China. Electronic address:

Phenol-formaldehyde resin microplastic (PF-MP) is one of the major inhalable microplastics in environments released from the manufacture, processing and usage of PF materials. The associated toxicities of PF-MP might be affected by photoaging. In this study, the dynamic evolutions of the oxidative potential (OP) and redox-active species, including environmentally persistent free radicals (EPFRs), reactive oxygen species (ROS), peroxides and conjugated carbonyls, as well as the associated cytotoxicity of PF-MP were systematically investigated as a result of the simulated sunlight irradiation. As the photoaging time extended, the OP of PF-MP increased. The contents of the produced conjugated carbonyls, ROS and PF-bound EPFRs due to light irradiation increased as well, and displayed significant correlations with the OP (Spearman r > 0.6, p < 0.05). The photoaged PF-MP distinctly increased the cellular ROS and reduced the cell viability of human lung epithelial adenocarcinoma cells (A549). The cytotoxicity of PF-MP showed a similar trend with the OP level in PF-MP, suggesting that the produced active species induced the in vitro toxicities. The results not only highlight the adverse health effects of photoaged PF-MP, but also provide new perspectives for the environmental risks of airborne MPs.
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http://dx.doi.org/10.1016/j.envint.2020.106137DOI Listing
December 2020

Synthesis of amino-functionalized TiCT MXene by alkalization-grafting modification for efficient lead adsorption.

Chem Commun (Camb) 2020 Sep 25;56(76):11283-11286. Epub 2020 Aug 25.

Institute of Oceanic and Environmental Chemical Engineering, Center for Membrane and Water Science &Technology, Zhejiang University of Technology, Hangzhou 310014, China.

High-quality amino-functionalized TiCT MXene (alk-MXene-NH) nanosheets were successfully synthesized by a facile alkalization-grafting modification for lead adsorption. The alk-MXene-NH achieved the highest BET specific area among all MXene-based adsorbents, and the generated abundant -NH, -OH and -ONa complexing groups exhibited strong interactions with lead ions, resulting in attractively high adsorption capacity.
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http://dx.doi.org/10.1039/d0cc04265jDOI Listing
September 2020

Simultaneous removal of chromium(VI) and tetracycline hydrochloride from simulated wastewater by nanoscale zero-valent iron/copper-activated persulfate.

Environ Sci Pollut Res Int 2020 Nov 16;27(32):40826-40836. Epub 2020 Jul 16.

College of Natural Resources and Environment, Northwest A&F University, Yangling, 712100, Shanxi, People's Republic of China.

In this paper, metallic copper (Cu) was supported on nanoscale zero-valent iron (nZVI) to form a nanoscale bimetallic composite (nZVI-Cu), which was used to activate persulfate (PS) to simultaneously remove the compound contaminants Cr(VI) and tetracycline hydrochloride (TCH) in simulated wastewater. nZVI, nZVI-Cu, and nZVI-Cu-activated PS (nZVI-Cu/PS) were characterized by SEM, TEM, XRD, and XPS. The effects of the bimetallic composite on Cr(VI) and TCH removal were compared in the nZVI, nZVI-activated PS (nZVI/PS), nZVI-Cu, and nZVI-Cu/PS systems. The results showed that nZVI and Cu can form a nanobimetallic system, which can create galvanic cells; thus, the galvanic corrosion of nZVI and the transfer of electrons are accelerated. For a single contaminant, the removal efficiency of Cr(VI) and TCH is the highest when nZVI is loaded with 3 wt% and 1 wt% Cu, respectively. The ratio of nZVI-Cu with 3 wt% Cu to PS is 7:1, and the removal efficiency of Cr(VI) and TCH compound contaminants is ~ 100% after 60 min under acidic conditions, which indicates that the Cr(VI) reduction and TCH oxidation were complete in the nZVI-Cu/PS system. The mechanisms of simultaneous removal of Cr(VI) and TCH in the nZVI-Cu/PS system are proposed. The removal of Cr is because of the adsorption-reduction effects of the nZVI-Cu bimetallic material. The degradation of TCH is mainly due to the action of oxidative free radicals generated by Fe-activated PS. The free radical capture experiments showed that SO- 4· plays a major role in the process of TCH degradation.
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http://dx.doi.org/10.1007/s11356-020-10120-8DOI Listing
November 2020

Remediation of organophosphorus pesticide polluted soil using persulfate oxidation activated by microwave.

J Hazard Mater 2021 01 1;401:123361. Epub 2020 Jul 1.

Key Laboratory of Pollution Processes and Environmental Criteria, Ministry of Education, Tianjin Key Laboratory of Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai University, Tianjin 300071, PR China.

Contaminated sites from pesticide industry have attracted global concern due to the characteristics of organic pollution with high concentrations and complete loss of habitat conditions. Remediation of organophosphorus pesticide polluted soil using microwave-activated persulfate (MW/PS) oxidation was investigated in this study, with parathion as the representative pesticide. Approximately 90 % of parathion was degraded after 90 min of MW/PS oxidation treatment, which was superior to those by single PS or MW treatment. Relatively greater performances for parathion degradation were obtained in a relatively larger PS dosage, higher microwave temperature, and lower organic matter content. Appropriate soil moisture favored parathion degradation in soil. SO, OH, O, and O generated in the MW/PS system all contributed to parathion degradation. Multiple spectroscopy analyses indicated that PO and PS bonds in parathion were destroyed after MW/PS oxidation, accompanied by generation of hydroxylated and carbonylated byproducts. The soil safety after parathion degradation was assessed via model prediction. Furthermore, MW/PS oxidation also exhibited great performance for degradation of other organophosphorus pesticides, including ethion, phorate, and terbufos.
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http://dx.doi.org/10.1016/j.jhazmat.2020.123361DOI Listing
January 2021

Probing the aging processes and mechanisms of microplastic under simulated multiple actions generated by discharge plasma.

J Hazard Mater 2020 11 20;398:122956. Epub 2020 May 20.

College of Natural Resources and Environment, Northwest A&F University, Yangling, Shaanxi Province, 712100, PR China; Key Laboratory of Plant Nutrition and the Agri-environment in Northwest China, Ministry of Agriculture, Yangling, Shaanxi, 712100, PR China. Electronic address:

Microplastics (MPs) are becoming one class of pollutants with high global concerns. Information regarding aging behaviors of MPs in complicated natural conditions is still lacking due to the very slow aging processes. In this study, discharge plasma oxidation was applied to simulate the various radical oxidation and physical effects naturally occurring in the environment to shed light on the aging behaviors and mechanisms of MPs, with polyvinyl chloride microplastic (PVC-MP) as a model. The surface morphology, particle size, specific surface area, crystallinity, and chemical compositions of PVC-MP were comprehensively characterized as a result of aging. The aging degree indicated by carbonyl index and oxygen-to-carbon ratio increased with the plasma oxidation intensity and duration. The aged PVC-MP was characterized as more O-containing functional groups, smaller particle size, larger specific surface area, higher hydrophilicity, and higher crystallinity. Consequently, the aged PVC-MP provided more sites for adsorption of tetrabromobisphenol (TBBPA) in solutions by forming hydrogen-bonds, and electrostatic force. The changes in the properties of the aged PVC-MP, and the strong adsorption with TBBPA led to unexpected synergistic toxic effects to Scenedesmus obliquus. The results provide direct evidences of aging processes of MPs and the potential environmental risks due to aging in the environment.
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http://dx.doi.org/10.1016/j.jhazmat.2020.122956DOI Listing
November 2020

Charge mediated interaction of polystyrene nanoplastic (PSNP) with minerals in aqueous phase.

Water Res 2020 Jul 27;178:115861. Epub 2020 Apr 27.

College of Natural Resources and Environment, Northwest A&F University, Yangling, Shaanxi, 712100, China; Key Laboratory of Plant Nutrition and the Agro-environment in Northwest China, Ministry of Agriculture, Yangling, Shaanxi, 712100, China. Electronic address:

A large number of plastic products potentially become smaller particles, including nanoplastics, under multiple actions in the environment. The interactions between nanoplastic particles and constituents in the environment, such as minerals, would greatly affect the transport, fate and toxic effects of nanoplastics. In this study, the interactions of polystyrene nanoplastic (PSNP) with four typical minerals, including goethite, magnetite, kaolinite and montmorillonite, in aqueous phase were investigated. The stability of PSNP colloidal suspension decreased in the presence of the positively charged goethite or magnetite, while it was not affected by the negatively charged montmorillonite and kaolinite, suggesting that there was a strong electrostatic attraction between PSNP and the two iron oxides. Incubation of PSNP with other three metal oxides with different surface charges, MnO, AlO and SiO, confirmed the importance of electrostatic interaction in the stability of PSNP suspension. The transmission electron microscopy (TEM) analysis and batch adsorption experiments indicated that PSNP was effectively adsorbed on goethite or magnetite due to the strong electrostatic attraction between them. The Fourier transform infrared spectra (FTIR) and two-dimensional correlation spectroscopy (2D-COS) analyses indicated that there was strong hydrogen bonding between the -OH (γ-FeOOH) of goethite and PSNP, contributing to the higher adsorption of PSNP on goethite than magnetite. These findings shed light on the interactions of PSNP with mineral surfaces, and potential fate of PSNP under natural conditions in the water environment.
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http://dx.doi.org/10.1016/j.watres.2020.115861DOI Listing
July 2020

Activation of persulfate and removal of ethyl-parathion from soil: Effect of microwave irradiation.

Chemosphere 2020 Aug 6;253:126679. Epub 2020 Apr 6.

Tianjin Key Laboratory of Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai University, Tianjin, 300071, PR China.

Advanced persulfate oxidation technology is widely used in organic pollution control of super fund sites. In recent years, microwave radiation has been proven a promising method for persulfate activation. However, most of the prior works were focused on the treatment of polluted water, but there are few reports aiming at contaminated sites, especially the knowledge of using microwave activated persulfate technology to repair pesticide-contaminated sites. In this study, an effective activation/oxidation method for the remediation of pesticide-contaminated soil, i.e., microwave/persulfate, was developed to treat soil containing ethyl-parathion. The concentration of persulfate, reaction temperature, and time were optimised. The results showed that up to 77.32% of ethyl-parathion was removed with the addition of 0.1 mmol·persulfate·g soil under the microwave temperature of 60 °C. In comparison, 19.43% of ethyl-parathion was removed at the same reaction temperature under the condition of water bath activated persulfate. Electron paramagnetic resonance (EPR) spectroscopy combined with spin-trapping technology was used to detect reactive oxidation species, and OH and SO were observed in the microwave/persulfate system. Quenching experiments suggested that ethyl-parathion was degraded by the generated OH and SO. Paraoxon, phenylphosphoric acid, 4-nitrophenol, dimethyl ester phosphate, and some alkanes were the dominant oxidative products identified by gas chromatography-mass spectrometry (GC-MS) analysis. A possible pathway for ethyl-parathion degradation was proposed in this study. The results obtained serve as the guidance to the development of remediation technologies involving persulfate and microwave for soil contaminated by organic contaminants such as pesticides.
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http://dx.doi.org/10.1016/j.chemosphere.2020.126679DOI Listing
August 2020

Molecular Phylogeny of an Avipoxvirus Isolated from Red-Flanked Blue Robin in China.

Avian Dis 2020 03;64(1):2-6

College of Animal Science and Technology, Jilin Agricultural University, No. 2888, Changchun, 130118, China,

We first report avipoxvirus (APV) infection and an isolate named APV/03/2016 from a red-flanked blue robin () captured at Songhua Lake Scenic Area in Jilin City (Jilin Province, China) on March 24, 2016. The partial sequence of the 4b core protein gene and DNA polymerase gene of APV/03/2016 suggests that the virus belongs to the subclade B1 cluster of clade B (canarypox virus). The BLAST results showed the highest similarity of the two genes with the Pacific shearwater-isolated strain SWPV-2 (KX857215), canarypox virus strain D98-11133 (GQ487567), canarypox virus strain ATCC VR-111 (AY318871), avipoxvirus Mississippi isolate P89 (KC018048), and avipoxvirus Wisconsin isolate P92 (KC018051). The results indicate that APV/03/2016 is a canarypox-like virus. These findings demonstrate the continuous emergence of new APV hosts such as red-flanked blue robins and suggest that monitoring of APV circulation and evolution should be strengthened for conservation.
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http://dx.doi.org/10.1637/0005-2086-64.1.2DOI Listing
March 2020

M2 bone marrow-derived macrophage-derived exosomes shuffle microRNA-21 to accelerate immune escape of glioma by modulating PEG3.

Cancer Cell Int 2020 27;20:93. Epub 2020 Mar 27.

1Department of Neurosurgery, Shandong Provincial Hospital Affiliated to Shandong University, 324 Jingwuweiqi Road, Jinan, 250021 Shandong China.

Background: Growing studies have focused on the role of microRNA-21 (miR-21) in glioma, thus our objective was to discuss the effect of M2 bone marrow-derived macrophage (BMDM)-derived exosomes (BMDM-Exos) shuffle miR-21 on biological functions of glioma cells by regulating paternally expressed gene 3 (PEG3).

Methods: Seventy-one cases of human glioma tissues and 30 cases of non-tumor normal brain tissues were collected and stored in liquid nitrogen. PEG3 and miR-21 expression in glioma tissues was tested. The fasting venous blood of glioma patients and healthy control was collected and centrifuged, and then the supernatant was stored at - 80 °C refrigerator. The contents of interferon (IFN)-γ and transforming growth factor-β1 (TGF-β1) in serum were tested by ELISA. Glioma cells and normal glial cells were cultured to screen the target cells for further in vitro experiments. BMDM-Exos was obtained by ultra-high speed centrifugation and then was identified. BMDM-Exos was co-cultured with U87 cells to detect the biological functions. The fasting venous blood of glioma patients was extracted and treated with ethylene diamine tetraacetic acid-K2 anti-freezing, and then CD8T cells were isolated. CD8T cells were co-cultured with U87 cells to detect the CD8T proliferation, cell cytotoxic activity, U87 cell activity, as well as IFN-γ and TGF-β1 levels. Moreover, BALB/c-nu/nu mice was taken, and the human-nude mouse glioma orthotopic transplantation model was established with U87 cells, and then mice were grouped to test the trends in tumor growth. The brain of mice (fixed by 10% formaldehyde) was sliced to detect the expression of Ki67 and proliferating cell nuclear antigen (PCNA). The spleen of mice was taken to prepare single-cell suspension, and the percentage of T lymphocytes in spleen to CD8T cells was detected.

Results: PEG3 expression was decreased and miR-21 expression was increased in glioma cells and tissues. Depleting miR-21 or restoring PEG3 suppressed growth, migration and invasion as well as accelerated apoptosis of glioma cells, also raised CD8T proliferation, cell cytotoxic activity, and IFN-γ level as well as decreased U87 cell activity and TGF-β1 level. BMDM-Exos shuttle miR-21 promoted migration, proliferation and invasion as well as suppressed apoptosis of glioma cells by reducing PEG3. Exosomes enhanced the volume of tumor, Ki67 and PCNA expression, reduced the percentage of CD8T cells in glioma mice.

Conclusion: BMDM-Exos shuffle miR-21 to facilitate invasion, proliferation and migration as well as inhibit apoptosis of glioma cells via inhibiting PEG3, furthermore, promoting immune escape of glioma cells.
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http://dx.doi.org/10.1186/s12935-020-1163-9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7099792PMC
March 2020

Bioavailability and Bioaccumulation of 6:2 Fluorotelomer Sulfonate, 6:2 Chlorinated Polyfluoroalkyl Ether Sulfonates, and Perfluorophosphinates in a Soil-Plant System.

J Agric Food Chem 2020 Apr 3;68(15):4325-4334. Epub 2020 Apr 3.

College of Natural Resources and Environment, Northwest A&F University, Yangling, Shaanxi Province 712100, P. R. China.

As emerging alternatives of legacy perfluoroalkyl substances, 6:2 fluorotelomer sulfonate (6:2 FTS), 6:2 chlorinated polyfluoroalkyl ether sulfonates (6:2 Cl-PFESA), and perfluorophosphinates (C6/C6 and C8/C8 PFPiAs) are supposed to be partitioned to soil and highly persistent in the environment. The uptake of novel per- and polyfluoroalkyl substances (PFASs) by plants represents a potential pathway for their transfer in the food chain. In this study, the bioavailability of these four novel PFASs in soil and the bioaccumulation characteristics in greenhouse-grown wheat ( L.), maize ( L.), soybean ( L. Merrill), and pumpkin ( L.) were investigated. The results indicated that these novel PFASs with higher hydrophobicity were more easily sequestrated in soil, and the fractions extracted by methanol could well describe their bioavailability, which could be stimulated by low-molecular-weight organic acids at rhizospheric concentrations. A negative relationship was found between root soil concentration factors (RSCFs) and hydrophobicity (log ) of the target PFASs. This correlation was also found in the translocation factors (TF) from roots to shoots. Furthermore, the uptake and transfer of the target PFASs were regulated by the protein contents in plant roots and shoots.
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http://dx.doi.org/10.1021/acs.jafc.0c00542DOI Listing
April 2020

Fenton aging significantly affects the heavy metal adsorption capacity of polystyrene microplastics.

Sci Total Environ 2020 Jun 5;722:137762. Epub 2020 Mar 5.

College of Natural Resources and Environment, Northwest A&F University, Yangling, Shaanxi 712100, China; Key Laboratory of Plant Nutrition and the Agro-environment in Northwest China, Ministry of Agriculture, Yangling, Shaanxi 712100, China. Electronic address:

Microplastics released into the environment undergo a variety of aging processes, however, information about the influence of aging on the adsorption behavior of microplastics is limited. In order to better understand the effect of aging polystyrene (PS) on the ability to adsorb heavy metal, HO and Fenton reagent were used to investigate the aging properties of PS. Aging PS with these two different aging agents at pH = 4 and room temperature for the same time. Physical and chemical characterization indicated that aging caused oxidation of the surface of PS and the formation of surface micro-cracks. Based on the 2D-COS analysis, the aging process of PS functional groups could occur in the following sequence: 1375 (C-OH) > 1739 (C=O) > 1182 cm (C-O-C) > 1716 (O-C=O). The adsorption experiments for Cd with two different concentrations were carried out by PS with different aging time at room temperature. The adsorption data showed that the adsorption capacity of Cd was significantly enhanced after aging compared with pristine PS, and the adsorption capacity of PS after Fenton aging treatment is much stronger than that after HO aging treatment. The kinetic analysis of the adsorption data indicates that the adsorption process is more consistent with the second-order kinetics than the first-order kinetics, and it is further concluded that the adsorption of Cd by PS is a relatively complicated process. According to the fitting results of adsorption isotherms, the adsorption process of pristine PS mainly occurs on the surface, but with the continuous aging, more adsorption sites may be exposed on the surface of PS, so it can be concluded that the adsorption mechanism of Cd by PS is the coexistence of physics and chemistry. This study indicates aging microplastics may have a significant impact on the destination and migration of metal contaminants, which deserves to be further concerned.
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http://dx.doi.org/10.1016/j.scitotenv.2020.137762DOI Listing
June 2020
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