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Soil saline–alkalization inhibits plant growth and development and seriously affects crop yields. Over their long-term evolution, plants have formed complex stress response systems to maintain species continuity. R2R3-MYB transcription factors are one of the largest transcription factor families in plants, widely involved in plant growth and development, metabolism, and stress response. Quinoa (Chenopodium quinoa Willd.), as a crop with high nutritional value, is tolerant to various biotic and abiotic stress. In this study, we identified 65 R2R3-MYB genes in quinoa, which are divided into 26 subfamilies. In addition, we analyzed the evolutionary relationships, protein physicochemical properties, conserved domains and motifs, gene structure, and cis-regulatory elements of CqR2R3-MYB family members. To investigate the roles of CqR2R3-MYB transcription factors in abiotic stress response, we performed transcriptome analysis to figure out the expression file of CqR2R3-MYB genes under saline–alkali stress. The results indicate that the expression of the six CqMYB2R genes was altered significantly in quinoa leaves that had undergone saline–alkali stress. Subcellular localization and transcriptional activation activity analysis revealed that CqMYB2R09, CqMYB2R16, CqMYB2R25, and CqMYB2R62, whose Arabidopsis homologues are involved in salt stress response, are localized in the nucleus and exhibit transcriptional activation activity. Our study provides basic information and effective clues for further functional investigation of CqR2R3-MYB transcription factors in quinoa. [ABSTRACT FROM AUTHOR]

Saline-alkali stress seriously affects the yield and quality of crops, threatening food security and ecological security. Improving saline-alkali land and increasing effective cultivated land are conducive to sustainable agricultural development. Trehalose, a nonreducing disaccharide, is closely related to plant growth and development and stress response. Trehalose 6-phosphate synthase (TPS) and trehalose-6-phosphate phosphatase (TPP) are key enzymes catalyzing trehalose biosynthesis. To elucidate the effects of long-term saline-alkali stress on trehalose synthesis and metabolism, we conducted an integrated transcriptome and metabolome analysis. As a result, 13 TPS and 11 TPP genes were identified in quinoa (Chenopodium quinoa Willd.) and were named CqTPS1-13 and CqTPP1-11 according to the order of their Gene IDs. Through phylogenetic analysis, the CqTPS family is divided into two classes, and the CqTPP family is divided into three classes. Analyses of physicochemical properties, gene structures, conservative domains and motifs in the proteins, and cis-regulatory elements, as well as evolutionary relationships, indicate that the TPS and TPP family characteristics are highly conserved in quinoa. Transcriptome and metabolome analyses of the sucrose and starch metabolism pathway in leaves undergoing saline-alkali stress indicate that CqTPP and Class II CqTPS genes are involved in the stress response. Moreover, the accumulation of some metabolites and the expression of many regulatory genes in the trehalose biosynthesis pathway changed significantly, suggesting the metabolic process is important for the saline-alkali stress response in quinoa. [ABSTRACT FROM AUTHOR]

Occupational exposure to trichloroethylene (TCE) has been associated with alterations in B‐cell activation factors and an increased risk of non‐Hodgkin's lymphoma (NHL). Here, we aimed to examine the biological processes influenced by TCE exposure to understand the underlying molecular mechanisms. This cross‐sectional molecular epidemiology study included data of 1317 targeted proteins in the serum from 42 TCE exposed and 34 unexposed factory workers in Guangdong, China. We used multivariable linear regressions to identify proteins associated with TCE exposure and examined their exposure‐response relationship across categories of TCE exposure (unexposed, low exposed: <10 ppm, high exposed: ≥10 ppm). We further examined pathway enrichment of TCE‐related proteins to understand their biological response. Occupational exposure to TCE was associated with lower levels of tumor necrosis factor receptor superfamily member 17 (TNFRSF17; β = −.08; p‐value =.0003) and kynureninase (KYNU; β = −.10, p‐value =.002). These proteins also showed a significant exposure‐response relation across the unexposed, low exposed, and high exposed workers (all p‐trends <.001, false discovery rate [FDR] < 0.20). Pathway analysis of TCE‐related proteins showed significant enrichment (FDR < 0.05) for several inflammatory and immune pathways. TCE exposure was associated with TNFRSF17, a key B‐cell maturation antigen that mediates B‐cell survival and KYNU, an enzyme that plays a role in T‐cell mediated immune response. Given that altered immunity is an established risk factor for NHL, our findings support the biological plausibility of linking TCE exposure with NHL. [ABSTRACT FROM AUTHOR]

Objectives: There has been concern over the possible risk of autoimmune diseases from exposure to trichloroethylene (TCE), an industrial solvent and common pollutant near hazardous waste sites. Studies of TCE-exposed lupus-prone mouse strains have reported increases in serum antinuclear antibodies (ANAs), a marker of autoimmunity, and autoimmune pathologic changes, while epidemiologic studies have provided limited support for an association between TCE exposure and scleroderma. To investigate exposure-related biologic evidence of autoimmunity in humans, we measured ANA levels in sera from a cross-sectional study of TCE-exposed (n=80) and TCE-unexposed (n=96) workers in Guangdong, China.Methods: Full-shift personal air exposure measurements for TCE were taken prior to blood collection. Serum ANAs were detected by immunofluorescence on HEp-2 cells. We calculated ORs and 95% CI relating levels of TCE exposure (categorised using tertiles as cut-points) and ANA positivity (1+ intensity at 1:320 dilution) using multivariable logistic regression.Results: Samples from 16 of 176 participants were ANA-positive. We found higher levels of TCE exposure (concentrations>17.27 ppm) to be associated with an elevated odds of ANA positivity (OR 4.7, 95% CI 1.3 to 16.8) compared with unexposed controls. This association remained after excluding two subjects with diagnosed autoimmune disease (OR 4.5, 95% CI 1.2 to 16.2). We did not observe an association with ANAs at lower exposure levels.Conclusions: Our findings, to our knowledge the first direct human evidence of an association between TCE exposure and systemic autoimmunity, provide biologic plausibility to epidemiologic evidence relating TCE and autoimmune disease. [ABSTRACT FROM AUTHOR]

Benzene, toluene, and xylenes (BTX) commonly co-exist. Exposure to individual components and BTX-rich mixtures can induce hematological effects. However, the hematological effects of long-term exposure to BTX are still unclear, and respective reference levels based on empirical evidence should be developed. We conducted a follow-up study in BTX-exposed petrochemical workers. Long-term exposure levels were quantified by measuring cumulative exposure (CE). Generalized weighted quantile sum (WQS) regression models and Benchmark Dose (BMD) Software were used to evaluate their combined effects and calculate their BMDs, respectively. Many hematologic parameters were significantly decreased at the four-year follow-up (p < 0.05). We found positive associations of CE levels of benzene, toluene, and xylene with the decline in monocyte counts, lymphocyte counts, and hematocrit, respectively (β > 0.010, Ptrend < 0.05). These associations were stronger in subjects with higher baseline parameters, males, drinkers, or overweight subjects (Pinteraction < 0.05). BTX had positive combined effects on the decline in monocyte counts, red-blood-cell counts, and hemoglobin concentrations (Ptrend for WQS indices < 0.05). The estimated BMDs for CE levels of benzene, toluene, and xylene were 2.138, 1.449, and 2.937 mg/m3 × year, respectively. Our study demonstrated the hematological effects of long-term BTX co-exposure and developed 8h-RELs of about 0.01 ppm based on their hematological effects. [ABSTRACT FROM AUTHOR]

Objectives: Occupational exposure to trichloroethylene (TCE) induces trichloroethylene hypersensitivity syndrome (TCEHS), which causes hypersensitivity dermatitis and hepatitis. However, whether TCE itself or its two metabolites, trichloroethanol (TCEOH) and trichloroacetic acid (TCA), are involved in TCEHS remains unclear. Therefore, in this study we explored the allergens causing TCEHS and characterized TCEHS‐related liver injury in guinea pigs. Method: The guinea pig maximization test was performed using TCE, TCEOH, and TCA as candidate allergens. Skin inflammation was scored, and liver function and histopathological changes were evaluated by biochemical tests and hematoxylin and eosin staining, respectively. Results: The sensitization rates for TCE, TCEOH, and TCA were 90.0%, 50.0%, and 0.0%, respectively. In the TCE and TCEOH experimental groups, the skin showed varying degrees of erythema with eosinophil granulocyte infiltration in the dermis. Additionally, serum alanine aminotransferase and γ‐glutamyl transpeptidase levels increased significantly, and histological analysis revealed focal hepatocellular necrosis with inflammatory cell infiltration in the liver. Conclusions: TCE is the main cause of allergy and TCEOH is a secondary factor for allergy in guinea pigs. TCE and TCEOH can cause immune‐mediated skin sensitization complicated by focal hepatic necrosis. [ABSTRACT FROM AUTHOR]

Human exposure to trichloroethylene (TCE) is linked to kidney cancer, autoimmune diseases, and probably non-Hodgkin lymphoma. Additionally, TCE exposed mice and cell cultures show altered DNA methylation. To evaluate associations between TCE exposure and DNA methylation in humans, we conducted an epigenome-wide association study (EWAS) in TCE exposed workers using the HumanMethylation450 BeadChip. Across individual CpG probes, genomic regions, and globally (i.e., the 450K methylome), we investigated differences in mean DNA methylation and differences in variability of DNA methylation between 73 control (< 0.005 ppm TCE), 30 lower exposed (< 10 ppm TCE), and 37 higher exposed (10 ppm TCE) subjects' white blood cells. We found that TCE exposure increased methylation variation globally (Kruskal-Wallis p-value = 3.75e-3) and in 25 CpG sites at a genome-wide significance level (Bonferroni p-value < 0.05). We identified a 609 basepair region in the TRIM68 gene promoter that exhibited hypomethylation with increased exposure to TCE (FWER = 1.20e-2). Also, genes that matched to differentially variable CpGs were enriched in the 'focal adhesion' biological pathway (p-value = 2.80e-2). All in all, human exposure to TCE was associated with epigenetic alterations in genes involved in cell-matrix adhesions and interferon subtype expression, which are important in the development of autoimmune diseases; and in genes related to cancer development. These results suggest that DNA methylation may play a role in the pathogenesis of TCE exposure-related diseases and that TCE exposure may contribute to epigenetic drift. [ABSTRACT FROM AUTHOR]

The increased applications and production of graphene oxide (GO) make the necessity to study information on the interaction of GO with minerals. In this work, adsorption and desorption were used to study the reversibility of interaction between GO and goethite/kaolinite. Result showed that the pH value, ionic strength, and temperature had significant effects on the adsorption and desorption behavior of GO. Interaction force was stronger between GO and goethite than that of kaolinite. The interaction may be attributed to the electrostatic, hydrogen-bonding, and Lewis acid base interactions. The irreversible interaction between GO and minerals may be a main mechanism for the observed desorption hysteresis. These results are important for evaluating the fate and health risk of GO in the environment. Image 1 • Adsorption and desorption of GO on cationic goethite and anionic kaolinite minerals was studied. • PH value, ionic strength, and temperature influence the adsorption and desorption behavior of GO. • Part of interaction between GO and minerals was irreversible. [ABSTRACT FROM AUTHOR]

Abstract: N‐alkylation of fulleropyrrolidines in the presence of polyformaldehyde and p‐toluenesulfonic acid was systematically investigated. With the addition of ketones/arylboronic acids, a series of novel N‐alkyl fulleropyrrolidines were formed. Nevertheless, in the absence of ketones/arylboronic acids, scarce N‐methyl fulleropyrrolidines were obtained with the aid of benzyl alcohol. Possible reaction pathways for the formation of N‐alkyl fulleropyrrolidines were proposed to elucidate the above reaction process. [ABSTRACT FROM AUTHOR]

Correction for 'Rationally designed 1D Ag@AgVO3 nanowire/graphene/protonated g-C3N4 nanosheet heterojunctions for enhanced photocatalysis via electrostatic self-assembly and photochemical reduction methods' by Shouwei Zhang et al., J. Mater. Chem. A, 2015, 3, 10119–10126, https://doi.org/10.1039/C5TA00635J. [ABSTRACT FROM AUTHOR]

The magnesium perchlorate-mediated reaction of [60]fullerene with aldehydes and triethylamine under air conditions afforded a series of rare cyclopentafullerenes in moderate to good yields with high stereoselectivity. A plausible reaction mechanism was suggested to elucidate the formation of cyclopentafullerenes. [ABSTRACT FROM AUTHOR]

Presented herein is a facile approach, which is easy, cost-effective, environmental benign without any secondary environmental pollution and no requirement for post purification, towards the synthesis of graphene oxides (GOs) with different oxidation degrees by ozone treatment. The synthesized GOs with controlled oxidation degrees can not only increase the quantity of oxygen-containing functional groups on GOs surfaces, but also decrease the sizes of GOs sheets to facilitate their dispersion abilities in aqueous solution, as revealed by characterization. The ozonized GOs were further applied as Co(II) adsorbents from aqueous solutions. The adsorption results showed that this adsorption processes was endothermic and spontaneous, and followed the pseudo-second-order kinetics and the Langmuir adsorption models. The microcosmic mechanism displayed that cobalt can complex with the oxygen-containing functional groups on GOs surfaces. As expected, increased adsorption capacities were observed by GOs with higher oxidation degrees. [ABSTRACT FROM AUTHOR]

Retraction of 'Formation of Fe3O4@MnO2 ball-in-ball hollow spheres as a high performance catalyst with enhanced catalytic performances' by Shouwei Zhang et al., J. Mater. Chem. A, 2016, 4, 1414–1422, https://doi.org/10.1039/C5TA08400H. [ABSTRACT FROM AUTHOR]

ABSTRACT A lactose-containing monomer, N-(2-lactosylethyl)acrylamide, was synthesized and polymerized with N-hydroxyethyl acrylamide and 1 wt % of N, N'-methylenebis(acrylamide) and potassium persulfate as the initiator to produce hydrogels. The weight percent of N-(2-lactosylethyl)acrylamide were increased from 0 to 100% in increments of 10%. Hydrogels were successfully produced with up to 90 wt % of N-(2-lactosylethyl)acrylamide. Gelation was confirmed by inverted vial tests and rheology measurements. The as-prepared hydrogels were used for papain stabilization against heat burden and papain that was loaded into hydrogels showed 45% more activity after heating as compared to papain that was heated without hydrogel stabilization. This hydrogel stabilization technique has potential applications in preserving enzyme activity. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016, 54, 2507-2514 [ABSTRACT FROM AUTHOR]

While the synthesis of heterogeneous catalysts is well established, it is extremely challenging to fabricate complex hollow structures with mixed transition metal oxides. Herein, we report a facile in situ growth process of SiO2@Fe3O4@MnO2, followed by an etching method to synthesize a hierarchical hollow structure, namely Fe3O4@MnO2 ball-in-ball hollow spheres (Fe3O4@MnO2 BBHs). The as-prepared Fe3O4@MnO2 BBHs were applied to degrade methylene blue (MB) by catalytic generation of active radicals from peroxymonosulfate (PMS), exhibiting the merits of excellent catalytic performance, easy separation, good stability and recyclability. In this architecture, the degradation process can be divided into three layers. The outer hierarchical MnO2 nanosheets could accumulate and transport the pollutants by electrostatic interactions and catalyze the generation of active radicals for degradation. Both the inner MnO2 nanosheets and the outer Fe3O4 hollows could produce active radicals to accelerate the pollutant degradation. The active catalytic sites also existed in the inner Fe3O4 hollows, which could further degrade the highly concentrated pollutants in the hollows. This work provides new strategies for the controllable synthesis of complex hollow structures and their application in environmental remediation. [ABSTRACT FROM AUTHOR]

ABSTRACT Covalently crosslinked polyurethane/urea polymers were synthesized using diamine monomers modified with pendant glucose groups and 2,4-toluene diisocyanate, poly(ethylene glycol) (PEG), and 1,1,1-tris(hydroxymethyl)ethane (triol) comonomers. The polymers showed shape memory behavior with a switching temperature dependent on the glass transition temperature. The glass transition temperature is tuned by varying the mole ratio between the glucose-diamine and PEG used in the polymerization. Increasing PEG content resulted in decreasing glass transition temperature, and a glass transition temperature of 39 °C, close to physiological temperatures, was obtained. The fixed shape showed gradual shape recovery behavior, but a fixity of 70% was achieved when the material was stored at 25 °C. The polymer recovered to the permanent shape when heated to 50 °C. Finally, the surface of a film of the polymer can be sulfated to achieve increased blood-compatibility without sacrificing the shape memory properties. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015, 53, 2252-2257 [ABSTRACT FROM AUTHOR]

1D Ag@AgVO3 nanowire/graphene/protonated g-C3N4 nanosheet (Ag@AgVO3/rGO/PCN) heterojunctions are fabricated via a simple electrostatic self-assembly process followed by a photochemical reduction method. In this hybrid structure, 1D Ag@AgVO3 nanowires penetrate through 2D nanosheets (graphene and PCN), forming a 3D hybrid photocatalyst, which is applied as an efficient visible light driven photocatalyst for organic pollutant degradation. Its enhanced photocatalytic activity is ascribed to the well-known electronic conductivity of 2D graphene, the intense visible light absorption of 1D Ag@AgVO3 nanowires, large surface areas and rapid photogenerated charge interface transfer and separation. Our results provide a facile way to fabricate hierarchical g-C3N4-based photocatalysts in a controlled manner and highlight promising prospects by adopting an integrative 1D and 2D nanomaterial strategy to design more efficient semiconductor-based composite photocatalysts with high photocatalytic activities and a wide spectral response toward environmental and energy applications. [ABSTRACT FROM AUTHOR]

Background: We documented previously the entity of trichloroethylene (TCE) hypersensitivity syndrome (THS) in occupational workers. Objectives: To identify the culprit causative compound, determine the type of hypersensitivity of THS, and establish a screening test for subjects at risk of THS. Methods: TCE and its main metabolites chloral hydrate (CH), trichloroethanol (TCOH) and trichloroacetic acid (TCA) were used as allergens at different concentrations in skin patch tests. The study included 19 case subjects diagnosed with occupational THS, 22 control healthy workers exposed to TCE (exposure >12 weeks), and 20 validation new workers exposed to TCE for <12 weeks free of THS. All subjects were followed-up for 12 weeks after the patch test. Results: The highest patch test positive rate in subjects with THS was for CH, followed by TCOH, TCA and TCE. The CH patch test positive rate was 100% irrespective of CH concentrations (15%, 10% and 5%). The TCOH patch test positive rate was concentration-dependent (89.5%, 73.7% and 52.6% for 5%, 0.5% and 0.05%, respectively). Lower patch test positive rates were noted for TCA and TCE. All patch tests (including four allergens) were all negative in each of the 22 control subjects. None of the subjects of the validation group had a positive 15% CH patch test. Conclusions: Chloral hydrate seems to be the culprit causative compound of THS and type IV seems to be the major type of hypersensitivity of THS. The CH patch test could be potentially useful for screening workers at risk of THS. [ABSTRACT FROM AUTHOR]

Polyurea-based synthetic glycopolymerscontaining sulfated glucose,mannose, glucosamine, or lactose as pendant groups have been synthesizedby step-growth polymerization of hexamethylene diisocyanate and correspondingsecondary diamines. The obtained polymers were characterized by gelpermeation chromatography, nuclear magnetic resonance spectroscopy,and Fourier transform infrared spectroscopy. The nonsulfated polymersshowed similar results to the commercially available biomaterial polyurethaneTECOFLEX in a platelet adhesion assay. The average degree of sulfationafter reaction with SO3was calculated from elemental analysisand found to be between three and four −OSO3groupsper saccharide. The blood-compatibility of the synthetic polymerswas measured using activated partial thromboplastin time, prothrombintime, thrombin time, anti-IIa, and anti-Xa assays. Activated partialthromboplastin time, prothrombin time, and thrombin time results indicatedthat the mannose and lactose based polymers had the highest anticoagulantactivities among all the sulfated polymers. The mechanism of actionof the polymers appears to be mediated via an anti-IIa pathway ratherthan an anti-Xa pathway. [ABSTRACT FROM AUTHOR]

Highlights: [•] Calculate the pyrolysis of O-methyl S-alkyl and S-methyl O-alkyl thiocarbonates. [•] Compare the kinetic and activation parameters for the experimental and theoretical results. [•] Elucidate the pyrolysis process by natural bond orbital analysis. [ABSTRACT FROM AUTHOR]

ABSTRACT N-alkyl urea peptoid oligomers containing glucose or mannose have been synthesized and characterized. The oligomers were subsequently polymerized using a step-growth polymerization with hexamethylene diisocyanate. Equal moles of both monomers were used to guarantee high-molecular weight polymers. The polymers were characterized by gel permeation chromatography, nuclear magnetic resonance, and Fourier-transform infrared spectroscopy, and contact angle measurements of solvent cast thin films. Sulfation of the final polymers was achieved using a SO3/pyridine complex in pyridine to afford the heparin biomimetics. The average degree of sulfation was calculated to be 3.5 sulfates per saccharide as measured by elemental analysis. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 5230-5238 [ABSTRACT FROM AUTHOR]