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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]

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]

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]

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]

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]

ABSTRACT Nitrate is an important nitrogen source used by plants. Despite of the considerable variation in the amount of soil nitrate, plants keep cytosolic nitrate at a homeostatic controlled level. Here we describe a set of homeostatic controller motifs and their interaction that can maintain robust cytosolic nitrate homeostasis at fluctuating external nitrate concentrations and nitrate assimilation levels. The controller motifs are divided into two functional classes termed as inflow and outflow controllers. In the presence of high amounts of environmental nitrate, the function of outflow controllers is associated to efflux mechanisms removing excess of nitrate from the cytosol that is taken up by low-affinity transporter systems (LATS). Inflow controllers on the other hand maintain homeostasis in the presence of a high demand of nitrate by the cell relative to the amount of available environmental nitrate. This is achieved by either remobilizing nitrate from a vacuolar store, or by taking up nitrate by means of high-affinity transporter systems (HATS). By combining inflow and outflow controllers we demonstrate how nitrate uptake, assimilation, storage and efflux are integrated to a regulatory network that maintains cytosolic nitrate homeostasis at changing environmental conditions. [ABSTRACT FROM AUTHOR]