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The increasing use of silver-containing nanoparticles (NPs) in commercial products has led to NP accumulation in the environment and potentially in food webs. Identifying the uptake pathways of different chemical species of NPs, such as Ag 2 S-NP and metallic AgNPs, into plants is important to understanding their entry into food chains. In this study, soybean Glycine max L. was hydroponically exposed to Ag 2 S-NPs via their roots (10-50 mg L -1 ) and stable-isotope-enriched 109 AgNPs via their leaves [7.9 μg (g fresh weight) -1 ]. Less than 29% of Ag in treated leaves (in direct contact with 109 AgNP) was accumulated from root uptake of Ag 2 S-NPs, whereas almost all of the Ag in soybean roots and untreated leaves sourced from Ag 2 S-NPs. Therefore, Ag 2 S-NPs are phytoavailable and translocate upward. During trophic transfer the Ag isotope signature was preserved, indicating that accumulated Ag in snails most likely originated from Ag 2 S-NPs. On average, 78% of the Ag in the untreated leaves was assimilated by snails, reinforcing the considerable trophic availability of Ag 2 S-NPs via root uptake. By highlighting the importance of root uptake of Ag 2 S-NPs in plant uptake and trophic transfer to herbivores, our study advances current understanding of the biogeochemical fate of Ag-containing NPs in the terrestrial environment.

Birnessites are abundant naturally occurring minerals with high sorption and oxidation capacity that could therefore play an important role in antimony (Sb) migration and transformation. There are various types of birnessites in the environment. However, little is known about the similarities and differences in Sb oxidation and sorption on birnessites with different properties. In this study, the behavior of Sb oxidation and sorption on two contrasting birnessites (δ-MnO 2 and triclinic birnessite (TrBir)) were investigated via batch and kinetic experiments and various spectroscopic techniques. Our results showed that the reaction mechanisms between Sb and the two birnessites were similar. The edge sites of birnessites were responsible for Sb(III) oxidation. Mn(IV) was reduced to Mn(III) and Mn(II), bound with birnessites and released to the solution, respectively. Because of the rapid rate of electron transfer of adsorbed Sb(III) to birnessites, the only Sb species on δ-MnO 2 after the oxidation reaction was Sb(V). Sb(V) was adsorbed at the edge sites of birnessites by replacing the OH group of birnessites, forming corner-sharing complexes with birnessites. However, the Sb sorption and oxidation capacities of the two birnessites were significantly different. Poorly-crystallized δ-MnO 2 exhibited a much higher oxidation and sorption capacity than well-crystallized TrBir because the former had many more edge sites than the latter. This study reveals the general mechanism of the reaction between Sb and birnessite and indicates that birnessite with a high number of edge sites would exhibit a huge capacity in Sb oxidation and sorption., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Perfluorooctanesulfonate (PFOS) is a toxic and persistent organic pollutant that can be widely detected in agricultural soils. In this study, two lettuce cultivars with low PFOS accumulation were screened out to reduce the exposure of PFOS to the human body via vegetable consumption. The screened low-PFOS cultivars may help to ensure food safety, despite planting in highly PFOS-polluted soils (1.0 mg/kg), due to their high tolerance to PFOS and 4.4-5.7 times lower shoot PFOS concentration than the high-PFOS cultivars. Protein content and protein-mediated transpiration played key roles in regulating PFOS accumulation in the lettuce cultivars tested. Lower protein content, lower stomatal conductance, and lower transpiration rate resulted in low PFOS accumulation. This study reveals the mechanism of forming low-PFOS accumulation of lettuce cultivars at physiological and biochemical levels and lays a foundation for developing a cost-effective and safe approach to grow vegetables in PFOS-polluted soils.

Sorption of perfluorooctanoic acid (PFOA), a toxic and persistent organic pollutant, by various size fractions of an agricultural soil at environmentally relevant concentrations was evaluated. PFOA sorption to all fractions involved both film diffusion and intraparticle diffusion with the rate-limiting step by the latter. PFOA isotherm data fitted a linear model. Organic matter (OM), cation exchange capacity, pore volume, and the Brunauer-Emmett-Teller area played key roles in PFOA sorption. The sorption capacity followed the order of humic acid > clay (0.15-4.4 mm) > fine silt (1.9-39.8 mm) > coarse silt (17.3-79.4 mm) > fine sand (45.7-316.2 mm) > coarse sand (120-724.4 mm), opposite to their contributions to overall PFOA sorption due to the influence of their percentage weight in the original soil. Percentage OM content was the dominant factor controlling the fraction contributions to overall PFOA sorption, demonstrating influence of the hydrophobic force on sorption. PFOA should be highly mobile and bioavailable in soil-crop systems due to the low log K oc values.

The cultivation of crop cultivars with low pollutant accumulation is an important strategy to reduce the potential health risks of food produced from polluted soils. In this study, we identified three loose-leaf lettuce cultivars with low accumulation of perfluorooctanoic acid (PFOA), a highly toxic and persistent organic pollutant. PFOA concentrations in the shoots of low-PFOA cultivars were 3.7-5.5-fold lower than those of high-PFOA cultivars. The identification of low-PFOA cultivars could contribute to ensuring food safety despite cultivation in highly polluted soils (1 mg/kg) based on the tolerable daily PFOA intake (1.5 μg/kg/d). We detected lower desorbing fractions of PFOA in rhizosphere soil, lower bioconcentration factors, and higher distribution in the cell walls and organelles of roots in low-PFOA cultivars, all of which are key factors in limiting PFOA uptake and translocation from soil to shoots, than in high-PFOA cultivars. This study reveals the mechanism of PFOA uptake from soil to crop and lays a foundation for establishing a cost-effective strategy to plant crops in polluted soil and reduce exposure risk due to persistent organic pollutants in crops., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Aniline aerofloat (AAF), a high-toxic organic flotation reagent, is widely used in mineral processing industry. However, little information on its environmental fate is available. AAF sorption to four types of agricultural soils at low concentrations (1-10 mg/L) was investigated using batch experiments. AAF sorption kinetics involved both boundary layer diffusion and intraparticle diffusion, following pseudo-second-order kinetics with equilibrium time within 120 min. Both Langmuir and Freundlich models fitted well the AAF sorption with the former better. Sorption of AAF to soils was a spontaneous and favorable physical sorption that was controlled by ion bridge effect and hydrophobic interaction that was related to van der Waals force and π-π coordination based on FTIR analyses. AAF sorption was remarkably affected by soil constituents, positively correlating with the contents of organic matter and clay. The relatively higher logK oc values (3.53-4.66) of AAF at environmental concentrations (1-5 mg/L) imply that soils are serving as a sink of AAF from beneficiation wastewater, posing great potential risks to environment and human health., (Copyright © 2018 Elsevier Inc. All rights reserved.)

iTRAQ analysis was used to map the proteomes of two Brassica parachinensis cultivars that differed in dibutyl phthalate (DBP) accumulation. A total of 5699 proteins were identified to obtain 152 differentially regulated proteins, of which 64 and 48 were specific to a high- and a low-DBP-accumulation cultivar, respectively. Genotype-specific biological processes were involved in coping with DBP stress, accounting for the variation in DBP tolerance and accumulation. Formation of high DBP accumulation in B. parachinensis might attribute to the more effective regulation of protein expression in physiology and metabolism, including (a) enhanced cell wall biosynthesis and modification, (b) better maintenance of photosynthesis and energy balance, (c) greatly improved total capacity for antioxidation and detoxification, and (d) enhanced cellular transport and signal transduction. Our novel findings contribute to a global picture of DBP-induced alterations of protein profiles in crops and provide valuable information for the development of molecular-assisted breeds of low-accumulation cultivars.

Responses of wheat (Triticum aestivum L.) seedling roots to the mixtures of copper (Cu), cadmium (Cd) and humic acids (HA) were investigated using the solution culture experiments, focusing on the interaction patterns between multiple metals and their influences on root proton release. A concentration-addition multiplication (CA) model was introduced into the modeling analysis. In comparison with metal ion activities in bulk-phase solutions, the incorporation of ion activities at the root cell membrane surfaces (CMs) (denoted as {Cu 2+ } 0 and {Cd 2+ } 0 ) into the CA model could significantly improve their correlation with RRE (relative root elongation) from 0.819 to 0.927. Modeling analysis indicated that the co-existence of {Cu 2+ } 0 significantly enhanced the rhizotoxicity of {Cd 2+ } 0 , while no significant effect of {Cd 2+ } 0 on the {Cu 2+ } 0 rhizotoxicity. 10 mg/L HA stimulated the root elongation even under metal stress. Although high concentration of metal ions inhibited the root proton release rate (ΔH + ), both the low concentration of metal ions and HA treatments increased the values of ΔH + . In HA-Cu-Cd mixtures, actions of metal ions on ΔH + values were varied intricately among treatments but well modeled by the CA model. We concluded from the CA models that the electrostatic effect is vitally important for explaining the effect of {Cu 2+ } 0 on the rhizotoxicity of {Cd 2+ } 0 , while it plays no unique role in understanding the influence of {Cd 2+ } 0 on the rhizotoxicity of {Cu 2+ } 0. Thus our study provide a novel way for modeling multiple metals behaviors in the environment and understanding the mechanisms of ion interactions., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Zn deficiency is a critical problem for many crops and human populations worldwide. Soil biochar amendment has recently been promoted as a sustainable agricultural practice. However, its effect on the bioavailability of micronutrients (especially Zn) to crops has not been fully addressed. This study investigated the impact of long-term biochar application in soils on Zn bioavailability to rice and wheat, using field experiments, and batch sorption/desorption experiments, in combination with extended X-ray absorption fine structure spectroscopy (EXAFS). In field soils biochar amendment increased total Zn content, but significantly decreased CaCl 2 -extractable Zn concentrations. Intriguingly, the uptake of Zn to wheat and rice grains was decreased. At high biochar application rates of 124 and 270t/ha the Zn concentrations in wheat grains (36.6 and 37.5mg/kg) reached a deficient level, lower than the recommended concentration of 45mg/kg. The batch experiments showed that biochar application at a cumulative rate of 10.5, 15.8, 31.5, 124, and 270t/ha significantly increased soil pH and soil organic matter (SOM) content, resulting in greater sorption and lower desorption of Zn. The EXAFS results demonstrated that the main forms of sorbed Zn were outer-sphere Zn complexes, Zn-illite, Zn-kaolinite and Zn-OM. The proportion of Zn-OM increased with increasing biochar application rates, suggesting that higher SOM might be more effective in immobilizing Zn and thus decreasing the Zn bioavailability. These results on the microscopic and macroscopic scales improved our understanding of the Zn bioavailability to crops, and raised potential concerns on the Zn deficiency in agricultural soils with long-term biochar application., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Objective: Although duloxetine has been approved for clinical therapy for diabetic peripheral neuropathic pain, the exact mechanism underlying the anti-allodynic effects in rat models of diabetes mellitus remains obscure. We attempted to identify whether duloxetine exerts anti-allodynic effects via inhibition of the TLR4-Myd88-dependent pathway in diabetic neuropathic pain (DNP) rats., Methods: An animal model of type 1 diabetic neuropathic pain was induced by intraperitoneal streptozotocin in 108 rats randomized into four groups: control, DNP, solvent control + DNP, and DNP + duloxetine. The DNP model establishment was validated, providing the MWT and TWL measurements were less than 80% of the baseline value on d14 after streptozotocin administration. The expressions of TLR4, Myd88, and NF-κB in the spinal dorsal horn were determined 21 days after streptozotocin injection by immunohistochemical assay and Western blot., Results: The results revealed that MWT and TWL in DNP, SC + DNP, and DLX + DNP groups were significantly decreased 14 days after STZ administration vs control (P < 0.05), while the pain thresholds in the DLX + DNP group were partially reversed. The expressions of TLR4, Myd88, and NF-κB in groups C, DNP, and SC + DNP were significantly increased, whereas duloxetine administration significantly downregulated the expressions of TLR4, Myd88, and NF-κB (P < 0.05)., Conclusions: Our findings indicated that duloxetine mitigated mechanical and thermal withdrawal thresholds in STZ-injected rats and rescued the overexpression of the TLR4-Myd88-dependent pathway in the spinal dorsal horn in these rats. Whether these changes directly contributed to the reduction of thermal and mechanical withdrawal behavior needs to be further explored.

Roxarsone (ROX) is an organoarsenic feed additive of increasing interest used in the poultry industry. Soybean responses to ROX stress were investigated in root exudates (REs) using two-dimensional correlation spectroscopy (2D-COS) with fluorescence and Fourier transform infrared spectra. Environmentally relevant ROX concentrations caused negligible toxicity to crop growth and photosynthesis activity but blackened soybean roots at high concentrations. 2D-COS analysis revealed that the protein-like fluorophore and C═C and C═O, aliphatic OH, and polysaccharide C-O-H moieties in soybean REs were most sensitive to ROX stress. Heterospectral 2D-COS results suggested that aromatic, amide I, quinone, ketone, and aliphatic functional groups were the foundational components of protein-like and short-wavelength excited humic-like fluorophores in soybean REs. Carboxyl and phenolic moieties were related to the long-wavelength excited humic-like fluorophore. Overall, 2D-COS combined with molecular-based spectral analysis of REs provided an innovative approach to characterize the physiological responses of crops to contaminants at sublethal levels.

Phosphate compounds and related materials are effective amendments for immobilization of heavy metals in contaminated soils. A greenhouse pot experiment with ryegrass (Lolium perenne) as the test plant was conducted to explore the impact of nanoparticle hydroxyapatite (HAP) on the immobilization and bioavailability of Cu and Zn in a heavy metal-polluted soil. The addition of nanoparticle HAP significantly decreased the uptake of Cu and Zn by ryegrass. As a result, the biomass of ryegrass increased as the rate of nanoparticle HAP increased. The toxicity characteristic leaching procedure (TCLP) and physiologically based extraction test (PBET) results of the treatments showed that the leachable and bioaccessible concentrations of Cu and Zn were significantly reduced after the soil stabilized with nanoparticle HAP. The XRD pattern of nanoparticle HAP was not changed by the presence of Cu and Zn, which suggests that Cu and Zn were immobilized by the formation of solid amorphous phosphate. Nanoparticle HAP was an effective material to immobilize heavy metals in contaminated soils.

Because of their versatile coordination modes and strong coordination ability for metals, triazole ligands can provide a wide range of possibilities for the construction of metal-organic frameworks. Three transition-metal complexes, namely bis(μ-1,2,4-triazol-4-ide-3-carboxylato)-κ 3 N 2 ,O:N 1 ;κ 3 N 1 :N 2 ,O-bis[triamminenickel(II)] tetrahydrate, [Ni 2 (C 3 HN 3 O 2 ) 2 (NH 3 ) 6 ]·4H 2 O, (I), catena-poly[[[diamminediaquacopper(II)]-μ-1,2,4-triazol-4-ide-3-carboxylato-κ 3 N 1 :N 4 ,O-[diamminecopper(II)]-μ-1,2,4-triazol-4-ide-3-carboxylato-κ 3 N 4 ,O:N 1 ] dihydrate], {[Cu 2 (C 3 HN 3 O 2 ) 2 (NH 3 ) 4 (H 2 O) 2 ]·2H 2 O} n , (II), (μ-5-amino-1,2,4-triazol-1-ide-3-carboxylato-κ 2 N 1 :N 2 )di-μ-hydroxido-κ 4 O:O-bis[triamminecobalt(III)] nitrate hydroxide trihydrate, [Co 2 (C 3 H 2 N 4 O 2 )(OH) 2 (NH 3 ) 6 ](NO 3 )(OH)·3H 2 O, (III), with different structural forms have been prepared by the reaction of transition metal salts, i.e. NiCl 2 , CuCl 2 and Co(NO 3 ) 2 , with 1,2,4-triazole-3-carboxylic acid or 3-amino-1,2,4-triazole-5-carboxylic acid hemihydrate in aqueous ammonia at room temperature. Compound (I) is a dinuclear complex. Extensive O-H...O, O-H...N and N-H...O hydrogen bonds and π-π stacking interactions between the centroids of the triazole rings contribute to the formation of the three-dimensional supramolecular structure. Compound (II) exhibits a one-dimensional chain structure, with O-H...O hydrogen bonds and weak O-H...N, N-H...O and C-H...O hydrogen bonds linking anions and lattice water molecules into the three-dimensional supramolecular structure. Compared with compound (I), compound (III) is a structurally different dinuclear complex. Extensive N-H...O, N-H...N, O-H...N and O-H...O hydrogen bonding occurs in the structure, leading to the formation of the three-dimensional supramolecular structure.

A robust method was developed for simultaneous determination of nine trace perfluoroalkyl carboxylic acids (PFCAs) in various edible crop matrices including cereal (grain), root vegetable (carrot), leafy vegetable (lettuce), and melon vegetable (pumpkin) using ultrasonic extraction followed by solid-phase extraction cleanup and high liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). The varieties of extractants and cleanup cartridges, the usage of Supelclean graphitized carbon, and the matrix effect and its potential influencing factors were estimated to gain an optimal extraction procedure. The developed method presented high sensitivity and accuracy with the method detection limits and the recoveries at four fortification levels in various matrices ranging from 0.017 to 0.180 ng/g (dry weight) and from 70% to 114%, respectively. The successful application of the developed method to determine PFCAs in various crops sampled from several farms demonstrated its practicability for regular monitoring of PFCAs in real crops.

Heavy metal stress in culture media is always rhizotoxic. Our study aims to investigate the role of negative potential (ψ 0 ) at root cell membrane surface (CMs) on modeling Zn 2+ toxicity to wheat seedling roots and to examine the effects of different nitrogen forms (NH 4 + and NO 3 - ) on ψ 0 and Zn rhizotoxicity. Solution culture experiments were conducted to measure the root elongation and Zn accumulation under Zn 2+ exposure. The role of two nitrogen forms in affecting Zn 2+ toxicity was compared, giving particular consideration to ψ 0 and Zn 2+ activities at CMs ({Zn 2+ } 0 ). Results showed that NH 4 + alleviates Zn 2+ rhizotoxicity and NO 3 - increases Zn 2+ rhizotoxicity. In modeling the rhizotoxicity, root length correlated better with {Zn 2+ } 0 than {Zn 2+ } b , and the predictive accuracy (r 2 ) of NH 4 + treatment increased from 0.748 to 0.917 when incorporation of {Zn 2+ } 0 and {Ca 2+ } 0 into analysis. Oppositely, ψ 0 played a limited role in modeling Zn 2+ rhizotoxicity and bioavailability in NO 3 - treated medium (r 2  = 0.609). Moreover, higher concentration of Zn in roots was found in NO 3 - treatment, compared with the NH 4 + treatment. ψ 0 rather than the rhizotoxicity data correlated better with Zn accumulation especially in the NO 3 - treatment (r 2  > 0.7), which meant the electrical driving force at CMs playing a dominant role in modeling the metal accumulation. In conclusion, the alleviatory role of NH 4 + on Zn toxicity and uptake was well explained and modeled by electrostatic effects at CMs. Though our data do not explore mechanisms for the NO 3 - -Zn 2+ interactions, we propose that ψ 0 worked better in affecting the driving force for root Zn uptake, than influencing metal bioavailability at CMs.

Due to their versatile coordination modes and metal-binding conformations, triazolyl ligands can provide a wide range of possibilities for the construction of supramolecular structures. Seven mononuclear transition metal complexes with different structural forms, namely aquabis[3-(4-methylphenyl)-5-(pyridin-2-yl)-1H-1,2,4-triazolato-κ 2 N 1 ,N 5 ]zinc(II), [Zn(C 14 H 11 N 4 ) 2 (H 2 O)], (I), bis[5-(4-methylphenyl)-3-(pyridin-2-yl)-1H-1,2,4-triazole-κ 2 N 3 ,N 4 ]bis(nitrato-κO)zinc(II), [Zn(NO 3 ) 2 (C 14 H 12 N 4 ) 2 ], (II), bis(methanol-κO)bis[3-(4-methylphenyl)-5-(pyridin-2-yl)-1H-1,2,4-triazolato-κ 2 N 1 ,N 5 ]zinc(II), [Zn(C 14 H 11 N 4 ) 2 (CH 4 O) 2 ], (III), diiodidobis[5-(4-methylphenyl)-3-(pyridin-2-yl)-1H-1,2,4-triazole-κ 2 N 3 ,N 4 ]cadmium(II), [CdI 2 (C 14 H 12 N 4 ) 2 ], (IV), bis[5-(4-methylphenyl)-3-(pyridin-2-yl)-1H-1,2,4-triazole-κ 2 N 3 ,N 4 ]bis(nitrato-κO)cadmium(II), [Cd(NO 3 ) 2 (C 14 H 12 N 4 ) 2 ], (V), aquabis[3-(4-methylphenyl)-5-(pyridin-2-yl)-1H-1,2,4-triazolato-κ 2 N 1 ,N 5 ]cobalt(II), [Co(C 14 H 11 N 4 ) 2 (H 2 O)], (VI), and diaquabis[3-(4-methylphenyl)-5-(pyridin-2-yl)-1H-1,2,4-triazolato-κ 2 N 1 ,N 5 ]nickel(II), [Ni(C 14 H 11 N 4 ) 2 (H 2 O) 2 ], (VII), have been prepared by the reaction of transition metal salts (Zn II , Cd II , Co II and Ni II ) with 3-(4-methylphenyl)-5-(pyridin-2-yl)-1H-1,2,4-triazole (pymphtzH) under either ambient or hydrothermal conditions. These compounds have been characterized by elemental analysis, IR spectroscopy and single-crystal X-ray diffraction. All the complexes form three-dimensional supramolecular structures through hydrogen bonds or through π-π stacking interactions between the centroids of the pyridyl or arene rings. The pymphtzH and pymphtz - entities act as bidentate coordinating ligands in each structure. Moreover, all the pyridyl N atoms are coordinated to metal atoms (Zn, Cd, Co or Ni). The N atom in the 4-position of the triazole group is coordinated to the Zn and Cd atoms in the crystal structures of (II), (IV) and (V), while the N atom in the 1-position of the triazolate group is coordinated to the Zn, Co and Ni atoms in (I), (III), (VI) and (VII).

Extracellular polymeric substances (EPS) isolated from bacteria, are abound of functional groups which can react with metals and consequently influence the immobilization of metals. In this study, we combined with Zn K-edge Extended X-ray Absorption Fine Structure (EXAFS), Fourier Transform Infrared (FTIR) spectroscopy, and High-Resolution Transmission Electron Microscopy (HRTEM) techniques to study the effects of EPS isolated from Bacillus subtilis and Pseudomonas putida on Zn sorption on γ-alumina. The results revealed that Zn sorption on aluminum oxide was pH-dependent and significantly influenced by bacterial EPS. At pH 7.5, Zn sorbed on γ-alumina was in the form of Zn-Al layered doubled hydroxide (LDH) precipitates, whereas at pH 5.5, Zn sorbed on γ-alumina was as a Zn-Al bidentate mononuclear surface complex. The amount of sorbed Zn at pH 7.5 was 1.3-3.7 times higher than that at pH 5.5. However, in the presence of 2 g L -1 EPS, regardless of pH conditions and EPS source, Zn + EPS + γ-alumina ternary complex was formed on the surface of γ-alumina, which resulted in decreased Zn sorption (reduced by 8.4-67.8%) at pH 7.5 and enhanced Zn sorption (increased by 10.0-124.7%) at pH 5.5. The FTIR and EXAFS spectra demonstrated that both the carboxyl and phosphoryl moieties of EPS were crucial in this process. These findings highlight EPS effects on Zn interacts with γ-alumina., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Roxarsone (ROX), the primary aromatic arsenical additive (AAA) used in animal feeding operations, is of increasing concern to environmental and human health due to land application of ROX-laden animal manure. Few studies have investigated the phytotoxicity, uptake mechanisms, and speciation of AAA in crop plants. In this study, wheat seedlings were employed to address these issues under hydroponic conditions. Compared to inorganic arsenic, ROX was less toxic to wheat root elongation. Wheat roots were more sensitive to ROX stress than shoots. For the first time, metabolized inorganic arsenic was detected in plants, although ROX was the predominant detected arsenic species in wheat seedlings. ROX uptake and toxicity to roots were inhibited by humic acid at concentrations higher than 50 mg/L due to interaction with ROX. Phosphate enhanced ROX uptake, but no trends were observed for ROX uptake in the presence of glycerol at concentrations lower than 250 mM. In addition, ROX uptake was significantly decreased by silicate (Si(IV), 0.5-10 mM) and the metabolic inhibitor, 2,4-dinitrophenol (0.5-2 mM), indicating that ROX transport into wheat roots was actively mediated by Si(IV)-sensitive transporters. These findings provide important insights into the fate and speciation of AAA in soil-water-plant systems relevant to human health., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Background: miR-153 has been found to be significantly decreased in non-small cell lung cancer (NSCLC) tissues; however, its clinical significance has not been investigated., Methods: The expression patterns of miR-153 in 137 pairs of human lung cancer tissues and adjacent normal lung tissues were analyzed using qRT-PCR. The relationships between miR-153 expression and clinicopathological parameters were examined by chi-square test. Kaplan-Meier method and the log-rank test were used to determine the difference in overall survival (OS) rates between two groups., Results: The expression of miR-153 was reduced significantly, compared with adjacent normal lung tissues (P<0.05). We observed that the expression level of miR-153 was positively correlated with the clinical stage (P=0.005), lymph node status (P=0.014), distant metastasis (P=0.004), and differentiated degree (P<0.001) in NSCLC patients. According to the Kaplan-Meier survival analysis, the patients with low miR-153 expression exhibited evidently poorer overall survival rates than those with high miR-153 expression (P=0.003). Multivariate analysis showed that the expression of miR-153 was an independent and significant factor associated with poor OS rates (P=0.002)., Conclusion: Decreased expression of miR-153 might be a potential unfavorable prognostic factor for patients with NSCLC, and further studies would be needed to prove our findings.

Objective: This study aims to explore the clinicopathologic features of 112 patients with mantle cell lymphoma (MCL)., Methods: Data from 112 MCL cases were collected, and immunohistochemical assay was conducted. Fluorescence in situ hybridization (FISH) detected a break in the CCND1 gene. The t-test was used in the statistical analysis., Results: All tumor cells in the 112 cases expressed B cell-related antigen, including 1 blastoid subtype and 1 polymorphic subtype. Among all cases, 106 expressed CD5 and 104 expressed cyclin D1. A break in the CCND1 gene was not found in 3 cases with CD5-MCL. IgH/CCND1 polyploid was observed in 2 classic cases., Conclusion: MCL is a type of special immunophenotypic B-cell lymphoma. The prognoses of blastoid and polymorphic subtypes are poor. Special subtypes should be classified during diagnosis.

The geochemical behavior and speciation of arsenic (As) in paddy soils is strongly controlled by soil redox conditions and the sequestration by soil iron oxyhydroxides. Hence, the effects of iron oxide reductive dissolution on the adsorption, transformation and precipitation of As(III) and As(V) in soils were investigated using batch experiments and synchrotron based techniques to gain a deeper understanding at both macroscopic and microscopic scales. The results of batch sorption experiments revealed that the sorption capacity of As(V) on anoxic soil was much higher than that on control soil. Synchrotron based X-ray fluorescence (μ-XRF) mapping studies indicated that As was heterogeneously distributed and was mainly associated with iron in the soil. X-ray absorption near edge structure (XANES), micro-X-ray absorption near edge structure (μ-XANES) and X-ray photoelectron spectroscopy (XPS) analyses revealed that the primary speciation of As in the soil is As(V). These results further suggested that, when As(V) was introduced into the anoxic soil, the rapid coprecipitation of As(V) with ferric/ferrous ion prevented its reduction to As(III), and was the main mechanism controlling the immobilization of As. This research could improve the current understanding of soil As chemistry in paddy and wetland soils., (Copyright © 2014 Elsevier B.V. All rights reserved.)

The object of this study is to develop a duplex fluorescent quantitative one-step RT-PCR assay for detection and quantitation of GI and GII norovirus. The specific primers, Taqman probes, optimized reaction solution and condition were used to develop the duplex fluorescent quantitative one-step RT-PCR assay. The sensitivity, specificity and reproducibility of the assay were evaluated. The assay was evaluated by testing the 100 specimen samples and compared with the reference assay conventional RT-PCR. The assay possessed high specificity for norovirus detection without any evident cross-reaction with enteric adenovirus, rotavirus or astrovirus. The detection limit of the real-time RT-PCR assay, for GI and GII norovirus was up to 10(3) copy/microL respectively. Compared with the conventional RT-PCR assay, the assay in this study had higher sensitivity with higher detection rate of norovirus in stool specimens. The duplex fluorescent quantitative one-step RT-PCR assay provides rapid, sensitive and reliable detection of GI and GII norovirus, and could be used as a laboratory diagnosis of norovirus in acute gastroenteritis patients.

Objective: To investigate the diagnostic value of microtubule-associated protein-2 (MAP-2) in biopsy of small cell lung carcinoma (SCLC)., Methods: Immunohistochemical technique was applied to detect the expression of synaptophysin (Syn), chromogranin A (CgA), CD56, MAP-2 and TTF-1 in 240 cases of SCLC from 2008 to 2011 in this hospital., Results: The positive rate of MAP-2 expression in SCLC was 95.8% (230/240), which was much higher than that of Syn (57.1%, 137/240), CgA (38.8%, 93/240) and CD56 (89.2%, 214/240). The sensitivity and accuracy of MAP-2 (99.1%, 95.4%) expression were also higher than those of Syn (58.3%, 42.5%), CgA (39.9%, 42.5%) and CD56 (91.5%, 87.9%)., Conclusions: MAP-2 is a new neuroendocrine marker with higher sensitivity and accuracy, and thus recommended to be added to the immunohistochemical panel for the diagnosis of SCLC.

Competitive adsorption kinetics of aqueous Pb2+ and Cu2+ on Nano-HAP surfaces were investigated by performing the adsorption kinetic experiments and comparing the change of zeta potentials and XRD-map before and after metal adsorption. The results showed that the adsorption quantity of Pb2+ on Nano-HAP was higher than that of Cu2+ in the single system. However, the competitive adsorption of Pb2+ and Cu2+ occurred in the co-existence system of Pb2+ and Cu2+. The adsorption quantity of Cu2+ on Nano-HAP increased, while that of Pb2+ decreased. The X-ray diffraction (XRD) and adsorption quantities of Ca2+ surface analysis indicated that dissolution-precipitation is the primary immobilization mechanism for Pb2+, while surface complexation and electrostatic adsorption account for Cu2+ sequestration. The adsorption quantities of Pb2+ and Cu2+ on Nano-HAP had marked linear relationship with Ca2+ release from Nano-HAP (R2 0.861-0.954). The adsorption kinetics were fitted with the equations of first-order, second-order, parabola, Elovich, double constant equation and LJ function, respectively, in which the second-order and power function kinetics equation fitted the results best. According to above results, the adsorption kinetics of Pb2+ and Cu2+ on Nano-HAP is a complex adsorption processes with both chemical reaction and physical adsorption.

Breast cancer metastasis suppressor 1 (BRMS1) is a predominantly nuclear protein that differentially regulates the expression of multiple genes, leading to suppression of metastasis without affecting orthotopic tumor growth. It has been demonstrated that BRMS1 may be correlated with advanced ovarian cancer. The aim of this study was to investi-gate the mechanisms of BRMS1 involvement in ovarian cancer metastasis. We constructed a plasmid containing a short hairpin RNA (shRNA) against BRMS1 and transfected it into the ovarian cancer cell line OVCAR3. Real-time reverse transcription polymerase chain reaction (real-time PCR) and Western blot analyses demonstrated that BRMS1 expression was efficiently downregulated. Stable suppression of BRMS1 significantly enhanced cell adhesion, migration, invasion and angiogenesis. We also found that chemokine receptor 4 (CXCR4) was upregulated at both the mRNA and protein levels. When approaching for the mechanism, we discovered that activation of the nuclear factor-κB (NF-κB) signaling pathway mediated CXCR4 upregulation, as demonstrated by the electrophoretic mobility shift assay (EMSA). Collectively, these results suggest that attenuation of BRMS1 may play a critical role in promoting migration, invasion and angiogenesis of ovarian cancer cells and BRMS1 may regulate the metastatic potential at least in part through upregulation of CXCR4 via NF-κB activation. Restoration of BRMS1 function is thus a potential new strategy for treating human ovarian cancer.

The effect of different soil types (red soil,yellow-brown soil and black soil) on the electrokinetic (EK)-oxidation remediation of heavy metals-organic pollutant contaminated soil was studied in laboratory-scale experiments. Copper and pyrene were chosen as model pollutant, and 12% H2O2, 10% hydroxypropyl-beta-cyclodextrin and 0.01 mol x L(-1) NaNO3 solution were added into the anode and cathode cell. The applied voltage was 1 V x cm(-1). After 15 days of EK remediation, the removal rate of pyrene and copper in red soil, yellow-brown soil and black soil were 38.5%, 46.8%, 51.3% for pyrene and 85.0%, 22.6%, 24.1% for Cu, respectively. The high pH of black soil produced high electroosmotic flow and increased the exposure of oxidants and pollutants, meanwhile the low clay content was also conducive to the desorption of pyrene. The low pH and organic matter of red soil affected the chemical species distribution of Cu and increased its removal rate. It is concluded that soil pH, clay content and heavy metal speciation in soil are the dominant factors affecting the migration and removal efficiency of pollutants.

Assessing environmental risks of metal contamination in soils is a complex task because the biologically effective concentrations of metals in soils vary widely with soil properties. The factors influencing the toxic effect of nickel (Ni) on root growth of barley (Hordeum vulgare) were re-evaluated using published data from both soil and hydroponic cultures. The electrical potential (ψ(0) (o) ) and ion activities ({I(z) }(0) (o) ) at the outer surfaces of root-cell plasma membranes (PMs) were computed as the basis of the re-evaluation. The reanalyses demonstrated that root growth was related to: the Ni(2+) activity at the PM surface, ({Ni(2+) }(0) (o) ); calcium (Ca) deficiency (related to {Ca(2+) }(0) (o) ); osmotic effects; and modification of intrinsic Ni(2+) toxicity by magnesium (Mg(2+) ; this appeared to exert an intrinsic (specific) ameliorating effect on intrinsic Ni(2+) toxicity). Electrostatic toxicity models (ETM) were developed to relate root growth to these factors (R(2)  > 0.751). Based on the ETM developed in soil culture and a Ni(2+) solid-solution partitioning model, critical metal concentrations in soils linked to a biological effect were well predicted for 16 European soils with a wide range of properties, indicating the potential utility of ETM in risk assessment of metals in terrestrial ecosystems., (© 2011 The Authors. New Phytologist © 2011 New Phytologist Trust.)

Quartz sand was selected as collector and saturated packed column was constructed to explore the effects of environmental factors (humic acid, pH and ionic strengths of the bulk solution) on the transport and fate of hydroxyapatite nanoparticles (Nano-HAP) through measuring zeta potentials and representative c(i)/c(0) of Nano-HAP. It was suggested that zeta potentials of Nano-HAP colloids became more negative with increasing humic acid concentration and the change in solution composition from 0 to 10 mg/L humic acid yielded an increase in the zeta potentials of Nano-HAP colloids from -15 mV to -55 mV and a sharp decrease in a (attachment efficiency) from 1.0 to 0.012, meanwhile, the increase in bulk solution pH yielded a slight decrease in a which enhancing its transportation in saturated packed column. However, zeta potentials of Nano-HAP colloids became less negative as the ionic strength of bulk solution increased due to the compression of diffuse double layer and yielded an increase in a which greatly impeded its mobility during the pore-water solution, meanwhile, divalent cations have significantly stronger influence on the transport of Nano-HAP than monovalent cations of the bulk solution. The increase in the concentration of monovalent cation (Na+) from 1 to 100 mmol/L yielded an increase in a from 0.030 to 0.13, and divalent cations (Ca2+) from 0.2 to 10 mmol/L yielded a greatly increase in alpha from 0.030 to 1.0. It is important to note that the results could considerably contribute to gain insights in the transport and fate of Nano-HAP in natured and engineered porous media.

Objective: This study was to explore the correlations between genetic variants in MMP2-1306C/T, TIMP2 2379C/T, TIMP2 303G/A and the genetic susceptibility to gastric carcinoma (GC) in Fujian province, China., Methods: A case-control study was conducted. Polymorphisms of MMP2-1306C/T, TIMP2 2379C/T, TIMP2 303G/A in 479 gastric carcinoma patients and 469 cancer-free controls, frequency-matched by age and sex, were determined by Matrix-Assisted Laser Desorption/Ionization Time of Flight Mass Spectrometry (MALDI-TOF-MS). Multivariate logistic regression analysis was used to evaluate the correlations between the polymorphisms with the susceptibility to gastric cancer. Tests for an interaction between the MMP2-1306C/T and TIMP2 2379C/T or TIMP2 303G/A were performed using the likelihood ratio test., Results: The frequencies of GG, AG, AA of TIMP2 303G/A in gastric cancer group were 55.9% (267/478), 38.7% (185/478) and 5.4% (26/478); and those in control group were 53.1% (243/458), 36.9% (169/458) and 10.0% (46/458), which showed a significant difference between the patient and control groups (χ(2) = 7.0, P = 0.03). As compared with AA genotype, patients with GG + AG had a significantly higher risk of the cancer with OR of 1.94 (95%CI: 1.2 - 3.2). The frequencies of GG + AG and AA of TIMP2 303G/A in the muscle group were 87.5% (70/80), 12.5% (10/80), however, those in the serosa and beyond group were 96.0% (382/398), 4.0% (16/398), respectively, which showed a significant difference between the patient in muscle group and the serosa and beyond group (χ(2) = 9.32, P = 0.002). As compared with AA genotype, patients with GG + AG had a significantly higher risk in tumor invasion with OR of 3.4 (95%CI: 1.5 - 7.8). The frequencies of CC + CT, TT of TIMP2 2379C/T in the lymphoma node non-metastasis group were 93.4% (113/121), and 6.6% (8/121), but those in the lymphoma node metastasis group were 98.6% (349/354) and 1.4% (5/354), respectively, which showed a significant difference between the patient in the lymphoma node non-metastasis group and in the lymphoma node metastasis group in genotype distributions of TIMP2 2379C/T) χ(2) = 9.16, P = 0.002). As compared with TT genotype, patients with CC + CT had a significantly higher risk in lymph node metastasis with OR of 4.9 (95%CI: 1.6 - 15.3). MMP2-1306C/T genotype was not associated with tumor size, tissue differentiation, invasion, TNM nor lymph node metastasis of gastric carcinoma (χ(2)(tumor size) = 0.05, P = 0.98; χ(2)(depth of invasion) = 1.87, P = 0.39; χ(2)(histological type) = 0.55, P = 0.76; χ(2)(LN metastasis) = 0.44, P = 0.80; χ(2)(TNM) = 2.6, P = 0.28). There was no significant interaction between the polymorphisms of the two genes observed (χ(2) values were 0.98 and 0.80, P values were 0.81 and 0.85)., Conclusion: Polymorphism of TIMP2 is significantly related with occurrence and development of GC and maybe acts as a new biomarker of GC in prognosis.

The Schiff base, C(16)H(12)N(2)S(2), has been synthesized by refluxing an ethano-lic solution of thio-phene-2-carbaldehyde and benzene-1,4-diamine. The center of the benzene ring is located on a crystallographic center of inversion. The dihedral angle between the benzene and thio-phene rings is 63.6 (1)°.

The purpose of this study was to characterize the individual effect of different cations (Ca(2+), Mg(2+), Na(+), K(+), and H(+)) on the acute toxicity of Cd to the earthworm Eisenia fetida. Higher activities of the considered cations increased the 48-h LC(50) (expressed as Cd(2+) activities) linearly to different extents in simulated soil solution. The conditional constants for the binding of H(+ )(log K = 5.41), Cd(2+ )(log K = 4.0), Ca(2+ )(log K = 3.35), Mg(2+ )(log K = 2.82), Na(+ )(log K = 1.57), and K(+ )(log K = 2.31) to the biotic ligand (BL) of E. fetida were derived from the toxicity data based on the biotic ligand model (BLM). Furthermore, it was calculated that on average 72% of the BL sites needed to be occupied by Cd(2+) to induce 50% lethal effect. Autovalidation of the model with the results of the test sets showed that 48-h LC(50 )could be predicted within a factor of two.

Glyphosate (GPS) is a non-selective, post-mergence herbicide that is widely used throughout the world. Due to the similar molecular structures of glyphosate and phosphate, adsorption of glyphosate on soil is easily affected by coexisting phosphate, especially when phosphate is applied at a significant rate in farmland. This paper studied the effects of phosphate on the adsorption of glyphosate on three different types of Chinese soils including two variable charge soils and one permanent charge soil. The results indicated that Freundlich equations used to simulate glyphosate adsorption isotherms gave high correlation coefficients (0.990-0.998) with K values of 2751, 2451 and 166 for the zhuanhong soil(ZH soil, Laterite), red soil(RS, Udic Ferrisol) and Wushan paddy soil (WS soil, Anthrosol), respectively. The more the soil iron and aluminum oxides and clay contained, the more glyphosate adsorbed. The presence of phosphate significantly decreased the adsorption of glyphosate to the soils by competing with glyphosate for adsorption sites of soils. Meanwhile, the effects of phosphate on adsorption of glyphosate on the two variable charge soils were more significant than that on the permanent charge soil. When phosphate and glyphosate were added in the soils in different orders, the adsorption quantities of glyphosate on the soils were different, which followed GPS-soil > GPS-P-soil = GPS-soil-P > P-soil-GPS, meaning a complex interaction occurred among glyphosate, phosphate and the soils.

The electrokinetic removal of chromium and copper from contaminated soils by adding lactic acid in cathode chamber as an enhancing reagent was evaluated. Two sets of duplicate experiments with chromium contaminated kaolinite and with a silty soil sampled from a superfund site in California of USA and polluted by Cr and Cu, were carried out in a constant current mode. Changes of soil water content and soil pH before and after the electrokinetic experiments, and variations of voltage drop and electroosmosis flow during the treatments were examined. The results indicated that Cr, spiked as Cr( VI ) in the kaolinite, was accumulated mainly in the anode chamber, and some of Cr and metal hydroxides precipitated in the soil sections in contact with the cathode, which significantly increased electrical energy consumption. Treatment of the soil collected from the site showed accumulation of large amounts of Cr and Cu in the anode chamber while none was detected in the cathode one. The results suggested that the two metals either complexed with the injected lactic acid at the cathode or existed as negatively charged complex, and electromigrated toward the anode under a voltage gradient.