Xu-Xiang Zhang

Nanjing University, Nan-ching, Jiangsu Sheng, China

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Publications (36)101.34 Total impact

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    ABSTRACT: Cross-omics profiling and phenotypic analysis were conducted to comprehensively assess the toxicities of source of drinking water (SDW), effluent of conventional treatment (ECT) and effluent of advanced treatment (EAT) in a water treatment plant. SDW feeding increased body weight, and relative liver and kidney weights of mice. Hepatic histopathological damages and serum biochemical alterations were observed in the mice fed with SDW and ECT, but EAT feeding showed no obvious effects. Transcriptomic analysis demonstrated that exposure to water samples caused differential expression of hundreds of genes in livers. Cluster analysis of the differentially expressed genes which generated by both microarrays and digital gene expression showed similar grouping patterns. Proteomic and metabolomics analyses indicated that drinking SDW, ECT and EAT generated 59, 145 and 41 significantly altered proteins in livers and 8, 2 and 0 altered metabolites in serum, respectively. SDW was found to affect several metabolic pathways including metabolism of xenobiotics by cytochrome P450 and fatty acid metabolism. SDW and ECT might induce molecular toxicities to mice, but the advanced treatment process can reduce the potential health risk by effectively removing toxic chemicals in drinking water.
    Journal of hazardous materials 01/2014; 271:57–64. · 4.14 Impact Factor
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    ABSTRACT: Recently, we have indicated that microcystin-LR, a cyanobacterial toxin produced in eutrophic lakes or reservoirs, can increase invasive ability of melanoma MDA-MB-435 cells; however, the stimulatory effect needs identification by in vivo experiment and the related molecular mechanism is poorly understood. In this study, in vitro and in vivo experiments were conducted to investigate the effect of microcystin-LR on invasion and metastasis of human melanoma cells, and the underlying molecular mechanism was also explored. MDA-MB-435 xenograft model assay showed that oral administration of nude mice with microcystin-LR at 0.001-0.1 mg/kg/d posed no significant effect on tumor weight. Histological examination demonstrated that microcystin-LR could promote lung metastasis, which is confirmed by Matrigel chamber assay suggesting that microcystin-LR treatment at 25 nM can increase the invasiveness of MDA-MB-435 cells. In vitro and in vivo experiments consistently showed that microcystin-LR exposure increased mRNA and protein levels of matrix metalloproteinases (MMP-2/-9) by activating phosphatidylinositol 3-kinase (PI3-K)/AKT. Additionally, microcystin-LR treatment at low doses (≤ 25 nM) decreased lipid phosphatase PTEN expression, and the microcystin-induced invasiveness enhancement and MMP-2/-9 over-expression were reversed by the PI3-K/AKT chemical inhibitor LY294002 and AKT siRNA, indicating that microcystin-LR promotes invasion and metastasis of MDA-MB-435 cells via the PI3-K/AKT pathway.
    Environmental Science & Technology 06/2013; · 5.26 Impact Factor
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    ABSTRACT: This study investigated the occurrence and abundance of class 1 integrons and related antibiotic resistance genes (ARGs) in a sewage treatment plant (STP) of China. Totally, 189 bacterial strains were isolated from influent, activated sludge and effluent, and 40 isolates contained the integons with a complete structure. The intl1-carrying isolates were found to harbor two types of gene cassettes: dfr17-aadA5 and aadA2, conferring resistances to trimethoprim and streptomycin, which were further confirmed by antimicrobial susceptibility analysis. Many other gene cassettes were carried on integron, including qnrVC1, catB-8-blaoxa-10-aadA1-aac(6'), aadB-aacA29b, aadA2, aac(6')-1b, aadA6 and aadA12, which were detected using DNA cloning. Quantitative real time PCR showed that over 99% of the integrons was eliminated in activated sludge process, but average copy number of integrons in given bacterial cells was increased by 56% in treated sewage. Besides integrons, other mobile gene elements (MGEs) were present in the STP with high abundance. MGEs and the associated ARGs may be wide-spread in STPs, which constitute a potential hot spot for selection of antibiotic resistant bacteria and horizontal transfer of ARGs.
    Journal of Environmental Biology 04/2013; 34(2 Spec No):391-9. · 0.68 Impact Factor
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    ABSTRACT: In order to comprehensively characterize the copper and cadmium resistance in activated sludge of a tannery wastewater treatment plant, a resistance protein database of the two heavy metals was manually created by retrieving annotated sequences and related information from the public databases and published literatures. The metagenomic DNA was extracted from the activated sludge for Illumina high-throughput sequencing, and the obtained 11,973,394 clean reads (1.61 Gb) were compared against the established databases using BLAST tool. Annotations of the BLAST hits showed that 222 reads (0.019 per thousand) and 197 reads (0.016 per thousand) were identified as copper and cadmium resistance genes, respectively. Among the identified cadmium resistance genes, czcA encoding cobalt-zinc-cadmium resistance protein had the highest abundance (83 reads, 0.0069 per thousand), which was further confirmed by annotation of the open reading frames predicted with the assembly contigs. Among the copper resistance genes, copA (66 reads, 0.0055 per thousand) was most abundant, followed by copK and cusR. Alignment against the Clusters of Orthologous Groups (COG) database also suggested that 87.26% of the matched reads were grouped in COG0474 (cation transport ATPase). This study may be practically helpful for exploring various functional genes in the environment using high-throughput sequencing and bioinformatics methods.
    Journal of Environmental Biology 04/2013; 34(2 Spec No):375-80. · 0.68 Impact Factor
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    ABSTRACT: Antibiotics are often used to prevent sickness and improve production in animal agriculture, and the residues in animal bodies may enter tannery wastewater during leather production. This study aimed to use Illumina high-throughput sequencing to investigate the occurrence, diversity and abundance of antibiotic resistance genes (ARGs) and mobile genetic elements (MGEs) in aerobic and anaerobic sludge of a full-scale tannery wastewater treatment plant (WWTP). Metagenomic analysis showed that Proteobacteria, Firmicutes, Bacteroidetes and Actinobacteria dominated in the WWTP, but the relative abundance of archaea in anaerobic sludge was higher than in aerobic sludge. Sequencing reads from aerobic and anaerobic sludge revealed differences in the abundance of functional genes between both microbial communities. Genes coding for antibiotic resistance were identified in both communities. BLAST analysis against Antibiotic Resistance Genes Database (ARDB) further revealed that aerobic and anaerobic sludge contained various ARGs with high abundance, among which sulfonamide resistance gene sul1 had the highest abundance, occupying over 20% of the total ARGs reads. Tetracycline resistance genes (tet) were highly rich in the anaerobic sludge, among which tet33 had the highest abundance, but was absent in aerobic sludge. Over 70 types of insertion sequences were detected in each sludge sample, and class 1 integrase genes were prevalent in the WWTP. The results highlighted prevalence of ARGs and MGEs in tannery WWTPs, which may deserve more public health concerns.
    PLoS ONE 01/2013; 8(10):e76079. · 3.73 Impact Factor
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    ABSTRACT: The metagenomic approach was applied to characterize variations of microbial structure and functions in raw (RW) and treated water (TW) in a drinking water treatment plant (DWTP) at Pearl River Delta, China. Microbial structure was significantly influenced by the treatment processes, shifting from Gammaproteobacteria and Betaproteobacteria in RW to Alphaproteobacteria in TW. Further functional analysis indicated the basic metabolic functions of microorganisms in TW did not vary considerably. However, protective functions, i.e. glutathione synthesis genes in 'oxidative stress' and 'detoxification' subsystems, significantly increased, revealing the surviving bacteria may have higher chlorine resistance. Similar results were also found in glutathione metabolism pathway, which identified the major reaction for glutathione synthesis and supported more genes for glutathione metabolism existed in TW. This metagenomic study largely enhanced our knowledge about the influences of treatment processes, especially chlorination, on bacterial community structure and protective functions (e.g. glutathione metabolism) in ecosystems of DWTPs.
    Scientific Reports 01/2013; 3:3550. · 2.93 Impact Factor
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    ABSTRACT: This study aimed to investigate the chlorination effects on microbial antibiotic resistance in a drinking water treatment plant. Biochemical identification, 16S rRNA gene cloning and metagenomic analysis consistently indicated that Proteobacteria were the main antibiotic resistant bacteria (ARB) dominating in the drinking water and chlorine disinfection greatly affected microbial community structure. After chlorination, higher proportion of the surviving bacteria was resistant to chloramphenicol, trimethoprim and cephalothin. Quantitative real-time PCRs revealed that sulI had the highest abundance among the antibiotic resistance genes (ARGs) detected in the drinking water, followed by tetA and tetG. Chlorination caused enrichment of ampC, aphA2, bla(TEM-1), tetA, tetG, ermA and ermB, but sulI was considerably removed (p < 0.05). Metagenomic analysis confirmed that drinking water chlorination could concentrate various ARGs, as well as of plasmids, insertion sequences and integrons involved in horizontal transfer of the ARGs. Water pipeline transportation tended to reduce the abundance of most ARGs, but various ARB and ARGs were still present in the tap water, which deserves more public health concerns. The results highlighted prevalence of ARB and ARGs in chlorinated drinking water and this study might be technologically useful for detecting the ARGs in water environments.
    Water Research 10/2012; · 4.66 Impact Factor
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    ABSTRACT: This study aimed to explore the molecular mechanisms behind the stimulation effects of microcystin-LR (a well-known cyanobacterial toxin produced in eutrophic lakes or reservoirs) on cancer cell invasion and matrix metalloproteinases (MMPs) expression. Boyden chamber assay showed that microcystin-LR exposure (>12.5 nM) evidently enhanced the invasion ability of the melanoma cells (MDA-MB-435). Tumor Metastasis PCR Array demonstrated that 24 h microcystin-LR treatment (25 nM) caused overexpression of eight genes involved in tumor metastasis, including MMP-2, MMP-9, and MMP-13. Quantitative real-time PCR, Western blotting and gelatin zymography consistently demonstrated that mRNA and protein levels of MMP-2/-9 were increased in the cells after microcystin-LR exposure (P < 0.05 each). Immunofluorescence assay and electrophoretic mobility shift assay revealed that microcystin-LR could activate nuclear factor kappaB (NF-κB) by accelerating NF-κB translocation into the nucleus and enhancing NF-κB binding ability. Furthermore, addition of NF-κB inhibitor in culture medium could suppress the invasiveness enhancement and MMP-2/-9 overexpression. This study indicates that microcystin-LR can act as a NF-κB activator to promote MMP-2/-9 expression and melanoma cell invasion, which deserves more environmental health concerns.
    Environmental Science & Technology 09/2012; 46(20):11319-26. · 5.26 Impact Factor
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    ABSTRACT: Mice were fed with source water (SW) and tap water (TW) for 90 d to evaluate hepatotoxicity induced by the drinking water. Histopathologic observation showed no obvious damage to hepatic tissue in the SW and TW groups. However, microarray analysis indicated that the SW and TW exposures affected many metabolic pathways, among which PPAR (peroxisome proliferator-activated receptors) signaling was most susceptible. Immunohistochemical staining demonstrated that both PPAR-α and PPAR-γ were significantly increased in the exposure groups compared to control. Enzyme-linked immunosorbent assay revealed that PPAR-α expression level was increased from 23.37±0.53 ng g(-1) liver weight in control group to 26.60±1.43 ng g(-1) liver weight in SW group and 27.68±1.10 ng g(-1) liver weight in TW group (p<0.05). For PPAR-γ, the expression level was also significantly enhanced from 0.83±0.07 ng g(-1) liver weight in control group to 1.11±0.20 ng g(-1) liver weight in SW group and 1.16±0.07 ng g(-1) liver weight in TW group (p<0.05). The SW and DW posed no obvious hepatotoxicity on mice and PPAR-α/-γ could be used as a novel biomarker to assess public health risk induced by slightly contaminated drinking water.
    Chemosphere 03/2012; 88(4):407-12. · 3.14 Impact Factor
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    ABSTRACT: The emerging antibiotic resistance genes in the aquatic environment have aroused public concern. As β-lactam is the most widely used group of antibiotics, β-lactam resistance genes were selected to investigate their distribution and diversity in the activated sludge from 15 geographically different sewage treatment plants (STPs) of China, Singapore, USA, and Canada. Specific PCR and quantitative real-time PCR (q-PCR) were used to investigate the occurrence and abundance of nine β-lactam resistance genes. Five genes (OXA-1, OXA-2, OXA-10, ampC, and TEM-1) were detected in most of the sludge collected, while three genes (mecA, CTX-M-1, and SME) were not found in any sludge sample. The total abundances of the six detected β-lactam resistance genes in the 15 STPs varied from 5.34 × 10(1) copies/ng DNA (ampC) to 5.49 × 10(4) copies/ng DNA (OXA-1). Overall, OXA-1 had the highest total concentration, followed by IMP and OXA-10. Noticeably, the abundances of TEM-1 in Chinese STPs were generally higher than those in the STPs of other countries, while the abundances of OXA-2 and IMP in the STPs of North America were much greater than those of East Asia. A total of 78 clones carrying β-lactam resistance genes were randomly selected from six clone libraries for phylogenetic diversity analysis; the similarity of these cloned genes to known β-lactam resistance genes with sequence identities ranged from 96% to 100%. Furthermore, OXA-1, ampC, and IMP were found to be more diverse than the other β-lactam resistance genes.
    Applied Microbiology and Biotechnology 12/2011; 95(5):1351-8. · 3.69 Impact Factor
  • Bing Wu, Yan Zhang, Xu-Xiang Zhang, Shu-Pei Cheng
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    ABSTRACT: A carcinogenic risk assessment of polycyclic aromatic hydrocarbons (PAHs) in source water and drinking water of China was conducted using probabilistic techniques from a national perspective. The published monitoring data of PAHs were gathered and converted into BaP equivalent (BaP(eq)) concentrations. Based on the transformed data, comprehensive risk assessment was performed by considering different age groups and exposure pathways. Monte Carlo simulation and sensitivity analysis were applied to quantify uncertainties of risk estimation. The risk analysis indicated that, the risk values for children and teens were lower than the accepted value (1.00E-05), indicating no significant carcinogenic risk. The probability of risk values above 1.00E-05 was 5.8% and 6.7% for adults and lifetime groups, respectively. Overall, carcinogenic risks of PAHs in source water and drinking water of China were mostly accepted. However, specific regions, such as Yellow river of Lanzhou reach and Qiantang river should be paid more attention. Notwithstanding the uncertainties inherent in the risk assessment, this study is the first attempt to provide information on carcinogenic risk of PAHs in source water and drinking water of China, and might be useful for potential strategies of carcinogenic risk management and reduction.
    Science of The Total Environment 12/2011; 410-411:112-8. · 3.26 Impact Factor
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    ABSTRACT: This study assessed the effects of microcystin-LR (MC-LR) exposure on matrix metalloproteinases (MMPs) expression and cancer cell migration. After male mice were orally administered with different concentrations of MC-LR for 270 d, histopathologic observation revealed an obvious hepatic lymphocyte infiltration or fatty degeneration. Immunohistochemical staining and enzyme-linked immunosorbent assay demonstrated that MC-LR treatment (even at 1 nM) caused up-regulated expressions of hepatic MMP-2/-9. Quantitative reverse-transcriptase PCR showed that the exposure to 80 nM MC-LR induced an increase of MMP-2/-9 mRNA levels by 1.0 and 1.9 fold. Breast cancer cells (MDA-MB-435s) were also cultured with MC-LR solutions and a wound healing assay demonstrated that MC-LR posed a time/dose-dependent stimulation effect on migration of the cancer cells. Gelatin electrophoresis and quantitative PCR showed significant increases in cellular MMP-2/-9 expressions after MC-LR exposure. This study indicated that chronic exposure to MC-LR could alter MMP-2/-9 expressions and stimulate cancer cell migration.
    Ecotoxicology and Environmental Safety 11/2011; 77:88-93. · 2.20 Impact Factor
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    ABSTRACT: A probability risk assessment of anthracene, benzo(a)pyrene, chrysene, fluorene, phenanthrene and pyrene was carried out to examine the ecological risk of these six polycyclic aromatic hydrocarbons (PAHs) in aquatic ecosystems in China. The literature on PAH concentrations in surface water in China was collected to evaluate the environmental exposure concentrations (EEC). The 10th percentile of predicted no observed effect concentration (PNEC(10%)) of PAHs, calculated according to the data from the USEPA AQUIRE database and regulatory reviews, was applied as the toxicity assessment endpoint. The ratio of EEC and PNEC(10%), expressed as a risk quotient (RQ), was used to characterize the risk value. Bootstrapping method and Monte Carlo simulation were utilized to calculate the distribution of EEC, PNEC(10%), RQ and associated uncertainties. Risk assessment showed that reliable maximum RQs of anthracene, benzo(a)pyrene, chrysene, fluorene and phenanthrene were in the range of 0.064-0.755, lower than the acceptable value of 1. However, the reliable maximum RQ of pyrene was 1.39, indicating its potential ecological risk. Notwithstanding the uncertainty, these results suggest that the aquatic ecosystems with high PAH concentrations might pose potential ecological risks, and concerted efforts are required to ensure that surface water is protected.
    Ecotoxicology 03/2011; 20(5):1124-30. · 2.77 Impact Factor
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    ABSTRACT: Water from Taihu Lake (China) is used as a drinking source. The frequency of contamination in Taihu Lake has increased over the past decade and the bloom-forming cyanobacteria are the dominant species during eutrophication. Cyanobacteria can produce various harmful secondary substances including microcystins capable of endangering human health and ecological safety. This study investigated toxicity of ingested Taihu Lake water on mice via hepatic histopathology and matrix metalloproteinase (MMP) expression. Water was sampled from four Taihu Lake locations, Meiliang Bay 2 group (M2), Meiliang Bay 1 group (M1), Lake Center (H) and Xukou Bay (X), along a gradient of decreasing degree of eutrophication. The experimental design consists of five groups of male mice (Mus musculus, ICR): one control and four groups ingesting water from the four sampling sites for 90 days. Compared to control, M1 and M2 mice showed hepatic histopathological changes including swollen, vacuolar degeneration or inflammatory. Immunohistochemical staining demonstrated a higher expression of MMP-2 proteins in M2 group and a lower expression of MMP-9 in M1. Enzyme-linked immunosorbent assay indicated that MMP-9 concentration was significantly reduced from 0.55 to 0.28 ng/g liver weight in M2 (p < 0.05). Real time PCR revealed a down-regulation of MMP-9 mRNA by 2.2 fold in M1 and an up-regulation of MMP-2 mRNA by 1.73 fold in H. Using this mouse model as a gauge of water toxicity, our results revealed that potential health risks induced by Taihu Lake water might arise from the use of this source water by local resident.
    Ecotoxicology 03/2011; 20(5):1047-56. · 2.77 Impact Factor
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    ABSTRACT: Integrons are elements that encode a site-specific recombination system that recognizes and captures mobile gene cassettes and are closely related to multiple resistances of environmental microorganisms. This study was undertaken to determine the efficiency of an activated sludge process to remove integrons. The prevalence and characteristics of class 1 integrons were investigated for bacterial species isolated from the activated sludge of Nanjing Jiangxinzhou sewage treatment plant (STP, China). A total of 189 bacterial strains were isolated from influent water, activated sludge and effluent water, and PCR-RFLP (Polymerase chain reaction--restriction fragment length polymorphism) of 16S rRNA gene showed that the isolated bacteria were Escherichia coli, Aeromonas veronii, Klebsiella spp., Aeromonas salmonicida and Aeromonas media. PCRs showed that 57 isolates contained class 1 integronase gene intI1. The integron detection frequency in the isolated strains was 20.4% for influent, 30.9% for activated sludge and 38.9% for effluent. Quantitative real-time PCR assay showed that the abundance of integrons in effluent was higher than that in influent. This study indicates that class 1 integrons are wide-spread in STPs which might be involved in multiple resistances in the activated sludge characterized by high biomass and biodiversity.
    Ecotoxicology 03/2011; 20(5):968-73. · 2.77 Impact Factor
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    ABSTRACT: Cytochrome P450 2E1 (CYP2E1) is a cytochrome P450 enzyme involved in styrene metabolism. This study compared the binding affinities between styrene and 11 mammalian CYP2E1 systems using bioinformatics methods. Firstly, amino acid sequences of CYP2E1s were obtained from the Swiss-Prot database. Then, taking the crystal structure of human CYP2E1 as a template, 3D models of the CYP2E1s of other mammals were constructed using the SWISS-MODEL program. Finally, the generated homology models were applied to calculate their docking capacities against styrene and polystyrene using the Surflex-Dock program, which could automatically dock ligands into a receptor's ligand binding site using a protomol based approach and assess the affinity by an empirically derived scoring function. Docking experiments showed that the studied mammalian CYP2E1s had high binding affinities with styrene. For polystyrene, the dimmer of styrene has high binding affinities with CYP2E1s, however, trimer and other high polymers were found hard to be docked into the CYP2E1s. The results of this study indicated that bioinformatics approaches might be useful tools to predict styrene and polystyrene affinities with mammalian CYP2E1s.
    Ecotoxicology 03/2011; 20(5):1041-6. · 2.77 Impact Factor
  • Xu-Xiang Zhang, Tong Zhang
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    ABSTRACT: Activated sludge was sampled from 15 sewage treatment plants (STPs) across China and other global locations to investigate the occurrence, abundance and diversity of tetracycline resistance genes (tet) in the STPs. Occurrence and abundance of 14 tet genes were determined using polymerase chain reaction (PCR) and quantitative real time PCR. Six genes (tet(A), tet(C), tet(G), tet(M), tet(S), and tet(X)) were detected in all the STPs, while no sludge sample contained tet(Q). Total concentration of the 14 genes was significantly different among the STPs and average tet abundance of the STPs varied greatly among the tet types (p<0.05). Tet(G) had the highest concentration in the STPs, followed by tet(C), tet(A) and tet(S). Phylogenetic diversity of the genes was investigated using DNA cloning. BLAST analysis showed that all of the 450 cloned sequences matched known tet genes, except for tet(G). The 56 tet(G) clones were grouped into 14 genotypes, among which type G24 had an identical sequence to tet(G) carried by Salmonella enterica or Acinetobacter baumannii, while the other sequences had low similarity to the known genes in GenBank. The results of this study might be useful to understand the diversity of these resistance genes in STPs.
    Environmental Science & Technology 03/2011; 45(7):2598-604. · 5.26 Impact Factor
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    Tong Zhang, Xu-Xiang Zhang, Lin Ye
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    ABSTRACT: The overuse or misuse of antibiotics has accelerated antibiotic resistance, creating a major challenge for the public health in the world. Sewage treatment plants (STPs) are considered as important reservoirs for antibiotic resistance genes (ARGs) and activated sludge characterized with high microbial density and diversity facilitates ARG horizontal gene transfer (HGT) via mobile genetic elements (MGEs). However, little is known regarding the pool of ARGs and MGEs in sludge microbiome. In this study, the transposon aided capture (TRACA) system was employed to isolate novel plasmids from activated sludge of one STP in Hong Kong, China. We also used Illumina Hiseq 2000 high-throughput sequencing and metagenomics analysis to investigate the plasmid metagenome. Two novel plasmids were acquired from the sludge microbiome by using TRACA system and one novel plasmid was identified through metagenomics analysis. Our results revealed high levels of various ARGs as well as MGEs for HGT, including integrons, transposons and plasmids. The application of the TRACA system to isolate novel plasmids from the environmental metagenome, coupled with subsequent high-throughput sequencing and metagenomic analysis, highlighted the prevalence of ARGs and MGEs in microbial community of STPs.
    PLoS ONE 01/2011; 6(10):e26041. · 3.73 Impact Factor
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    ABSTRACT: In order to investigate the potential effects of microcystin-LR (MC-LR) on the expression of metalloproteinases (MMPs), Mice were orally administered with MC-LR in drinking water (0, 1, 40 and 80 μg/L) for 180 d, and hepatic MMP-2/-9 expression was evaluated at the levels of enzyme activity, protein level and mRNA expression. Histopathologic observation showed the obvious hepatic lymphocyte infiltration and fatty degeneration in the mice exposed to 40 and 80 μg/L MC-LR. Immunohistochemical staining and enzyme-linked immunosorbent assay (ELISA) revealed that excess MMP-2/-9 proteins were produced in livers of the mice exposed to MC-LR at the higher concentrations. Hepatic MMP-9 level was elevated from 0.6 ng/g liver weight in control to 1.4 ng/g liver weight in 80-μg/L group, but a slight increase was found for MMP-2 level. Real time PCR showed that MMP-2/-9 mRNA expression was up-regulated by 6.9 fold and 5.0 fold after 80-μg/L-MC treatment, respectively. MMP-2/-9 expression showed a good dose-dependent manner at both protein and mRNA levels. ELISA demonstrated that MC-LR stimulated phosphorylation of mitogen-activated protein kinases, a potential signal transduction pathway of the MMP-2/-9 expression alteration. This study revealed a significant alteration in hepatic MMP-2/-9 expression induced by MC-LR, which might be involved in cell invasion and metastasis.
    Toxicology Letters 10/2010; 199(3):377-82. · 3.15 Impact Factor
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    ABSTRACT: DNA micorarray was used to analyze hepatic transcriptional profile of male mice (Mus musculus) after 35-d intragastric perfusion treatment with purified terephthalic acid (PTA) manufacturing wastewater. Haematological analysis demonstrated that the levels of glutamyl transferase and lactate dehydrogenase in serum were significantly decreased, and DNA microarray showed that a total of 306 genes were differentially expressed in PTA wastewater-treated mice. According to Kyoto encyclopedia of genes and genomes pathway database, the differentially expressed genes were mainly grouped to metabolic pathways (58 genes) and biological processes (101 genes). PTA wastewater had significant impacts upon metabolisms of lipid, carbohydrate, amino acid, vitamin and nucleotide. Several signal transduction pathways are most susceptible to PTA wastewater, including mitogen-activated protein kinases, Janus kinase/signal transducers and activators of transcription and calcium signaling pathways. Potential public health problems may arise from the discharge of PTA wastewater into the environment.
    Journal of hazardous materials 09/2010; 181(1-3):1121-6. · 4.14 Impact Factor

Publication Stats

176 Citations
101.34 Total Impact Points


  • 2005–2014
    • Nanjing University
      • School of Environment
      Nan-ching, Jiangsu Sheng, China
  • 2009–2011
    • The University of Hong Kong
      • Department of Civil Engineering
      Hong Kong, Hong Kong
  • 2008
    • Nanjing Environmental Science Institute
      Nan-ching-hsü, Jiangxi Sheng, China
  • 2006
    • Northeast Institute of Geography and Agroecology
      • Research Center for Eco-Environmental Sciences
      Beijing, Beijing Shi, China