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The existence of nitrate and dissolved organic matter (DOM) in water can react with chlorine disinfectant to form chloronitromethane (CNM) with high toxicity. The purpose of this study was to investigate the effects of NH4NO3, NaNO3 and Ca(NO3)2 on the formation of CNM under UV/chlorine treatment when glucose was used as the carbon source. The results showed that the formation of CNM from nitrate and glucose was raised first and then decreased. Among three types of nitrate, the potential of forming CNM from NH4NO3 was the largest. The concentration of CNM increased with increasing glucose concentration and UV intensity, while it decreased with increasing pH from 6 to 8. The analysis of various nitrogen showed that NH3-N and were converted into dissolved organic nitrogen (DON) under UV/chlorine treatment. The formation pathways of CNM from nitrate and glucose had been inferred under UV/chlorine treatment. Actual water samples were used to verify the laws found in the laboratory. The study could provide the development of a new disinfection method for water treatment and be useful for controlling the generation of CNM under UV/chlorine treatment. HIGHLIGHTS The maximum concentration of CNM from nitrates was promoted by UV/chlorine treatment.; The potential of forming CNM from NH4NO3 was larger than NaNO3 and Ca(NO3)2 under UV/chlorine treatment.; There was an insignificant difference in the formation of CNM between NaNO3 and Ca(NO3)2, except for alkaline conditions.

Aflatoxin B1 (AFB1), a food contaminant derived from Aspergillus fungi, has been reported to cause hepatic immunotoxicity via inflammatory infiltration and cytokines release. As a pro-inflammatory factor, cyclooxygenase-2 (COX-2) is widely involved in liver inflammation induced by xenobiotics. However, the mechanism by which AFB1-induced COX-2 regulates liver inflammatory injury via hepatocytes-Kupffer cells (KCs) crosstalk remains unclear and requires further elucidation. Here, we established a COX-2 upregulated model with AFB1 treatment in vivo (C57BL/6 mice, 1 mg/kg body weight, i.g, 4 weeks) and in vitro (human liver HepaRG cells, 1 μM for 24 h). In vivo, AFB1-treated mice exhibited NLRP3 inflammasome activation, inflammatory infiltration, and increased recruitment of KCs. In vitro, dephosphorylated COX-2 by protein phosphatase 2A (PP2A)-B55δ promoted NLRP3 inflammasome activation, including mitochondrial translocation of NLRP3, caspase 1 cleavage, and IL-1β release. Moreover, phosphorylated COX-2 at serine 601 (p-COX-2Ser601) underwent endoplasmic reticulum (ER) retention for proteasome degradation. Furthermore, pyroptosis and inflammatory response induced by AFB1 were relieved with COX-2 genetic (siPTGS2) intervention or pharmaceutic (celecoxib, 30 mg/kg body weight, i.g, 4 weeks) inhibition of COX-2 via NLRP3 inflammasome suppression in vivo and in vitro. Ex vivo, in a co-culture system with murine primary hepatocytes and KCs, activated KCs induced by damaged signals from pyroptotic hepatocytes, formed a feedback loop to amplify NLRP3-dependent pyroptosis of hepatocytes via pro-inflammatory signaling, leading to liver inflammatory injury. Taken together, our data suggest a novel mechanism that protein quality control of COX-2 determines the intracellular distribution and activation of NLRP3 inflammasome, which promotes liver inflammatory injury via hepatocytes-KCs crosstalk.

Objective: The Yip1 domain family (YIPF) proteins were proposed to function in endoplasmic reticulum (ER) to Golgi transport and maintenance of the morphology of the Golgi, which were homologues of yeast Yip1p and Yif1p. YIPF3, the member 3 of YIPF family was a homolog of Yif1p. The aim of present study was to investigate the expression and regulation mechanism of porcine YIPF3.Methods: Quantitative realtime polymerase chain reaction (qPCR) was used to analyze porcine YIPF3 mRNA expression pattern in different tissues and pig kidney epithelial (PK15) cells stimulated by polyinosine-polycytidylic acid (poly [I:C]). Site-directed mutations combined with dual luciferase reporter assays and electrophoretic mobility shift assay (EMSA) were employed to reveal transcription regulation mechanism of porcine YIPF3.Results: Results showed that the mRNA of porcine YIPF3 (pYIPF3) was widely expressed with the highest levels in lymph and lung followed by spleen and liver, while weak in heart and skeletal muscle. Subcellular localization results indicated that it expressed in Golgi apparatus and plasma membranes. Upon stimulation with poly (I:C), the level of this gene was dramatically up-regulated in a time- and concentration-dependent manner. pYIPF3 core promoter region harbored three cis-acting elements which were bound by ETS proto-oncogene 2 (ETS2), zinc finger and BTB domain containing 4 (ZBTB4), and zinc finger and BTB domain containing 14 (ZBTB14), respectively. In which, ETS2 and ZBTB4 both promoted pYIPF3 transcription activity while ZBTB14 inhibited it, and these three transcription factors all played important regulation roles in tumorigenesis and apoptosis.Conclusion: The pYIPF3 mRNA expression was regulated by ETS2, ZBTB4, and ZBTB14, and its higher expression in immune organs might contribute to enhancing ER to Golgi transport of proteins, thus adapting to the immune response.

Mitophagy, a selective autophagy of mitochondria, clears up damaged mitochondria to maintain cell homeostasis. We performed high-content analysis (HCA) to detect the increase of PINK1, an essential protein controlling mitophagy, in hepatic cells treated with several nanoparticles (NPs). PINK1 immunofluorescence-based HCA was more sensitive than assays and detections for cell viability and mitochondrial functions. Of which, superparamagnetic iron oxide (SPIO)-NPs or graphene oxide-quantum dots (GO-QDs) was selected as representatives for positive or negative inducer of mitophagy. SPIO-NPs, but not GO-QDs, activated PINK1-dependent mitophagy as demonstrated by recruitment of PARKIN to mitochondria and degradation of injured mitochondria. SPIO-NPs caused the loss of mitochondrial membrane potential, decrease in ATP, and increase in mitochondrial reactive oxide species and Ca2+. Blocking mitophagy with PARKIN siRNA aggravated the cytotoxicity of SPIO-NPs. Taken together, PINK1 immunofluorescence-based HCA is considered to be an early, sensitive, and reliable approach to evaluate the bioimpacts of NPs.

Ultra-small superparamagnetic iron oxide nanoparticles (USPIO-NPs) are widely used as clinical magnetic resonance imaging contrast agents for hepatic diseases diagnosis. USPIO-NPs often damage the hepatocytes and affect the function of liver but its mechanism of action remains unclear. In the present study, USPIO-NPs caused higher cytotoxicity and lactate dehydrogenase (LDH) leakage in hepatic L02 cells than SPIO-NPs. Subsequently, USPIO-NPs affected more genes’ expression than SPIO-NPs analyzed through microarray and bioinformatics analysis. The affected genes were involved in several biological processes, including calcium ion homeostasis, inflammatory response-related leukocyte chemotaxis, and migration. In addition, the level of endoplasmic reticulum (ER) calcium ion was increased by USPIO-NPs. USPIO-NPs also upregulated the genes related to acute-phase inflammation, including IL1B, IL6, IL18, TNFSF12, TNFRSF12, SAA1, SAA2, JAK1, STAT5B, and CXCL14. Furthermore, interleukin-6 (IL-6) secretion was elevated by USPIO-NPs as detected using ELISA. On the other hand, USPIO-NPs changed the morphology of ER and triggered the ER stress and unfolded protein response PERK/ATF4 pathway. Furthermore, blocking ER stress with inhibitor or ATF4 small interfering RNA counteracted IL-6-related acute-phase inflammation and cytotoxicity caused by USPIO-NPs. Taken together, we found that the USPIO-NPs could trigger stronger IL-6-related acute-phase inflammation than SPIO-NPs in hepatocytes. We demonstrated, for the first time, that IL-6-related acute-phase inflammation caused by NPs was regulated by PERK/ATF4 signaling. The PERK/ATF4 pathway explored in this study could be a candidate for diagnostic and therapeutic target against NPs-induced liver injury and cytotoxicity, which would be helpful for USPIO-NPs medical application.

Cobalt(II) bipyridine bisphenolate (CoII(BpyBph)) was applied to mediate the controlled/living radical polymerization of vinyl acetate (VAc), methyl acrylate (MA), and other vinyl monomers such as N-vinylpyrrolidone (NVP) and acrylonitrile (AN). The living characters of linear increased molecular weight with monomer conversion, relatively narrow molecular weight distribution, and the synthesis of block copolymer demonstrated by the formation of PVAc-b-PNVP were all observed. The polymerization of VAc was proposed to be mediated by the degenerative transfer (DT) process, but the polymerization of MA should be mainly controlled by the reversible termination (RT) process since the equilibrium constant (Keq = [CoIII–R]/[CoII][R•]) between cobalt(II) and organocobalt(III) was measured as 8.6 × 107 M–1. The correlation between Keq and the redox potential (E1/2) of cobalt complexes was preliminarily observed as a higher E1/2 leading to a larger Keq.

The preparation of a series of ligand precursors that feature imidazo[1,2-a]pyridine and amido functional groups is reported. The reactions between the new ligand precursors, pyridine, and palladium acetate in DMF afforded monodentate PdII abnormal (mesoionic) carbene complexes. An isomeric PdII normal carbene complex with a formally identical steric environment to that of the abnormal carbene counterpart was also prepared. The isomeric pairs were characterized by X-ray structural studies. Under different complexation conditions, in which PdCl2 was employed as metal precursor, a zwitterionic CC-type palladacycle formed by the C–H activation at the ortho-N-phenyl and methylene carbon atoms was obtained. The use of a similar ligand precursor with an NH instead of an NMe group produced a zwitterionic palladalactam complex. In contrast to the previous work in the literature, owing to the rigidity of the fused heterocyclic ring, the palladalactam complex did not undergo intramolecular proton transfer through the coordinated N atom. Overall, we demonstrated that proper modification of the structures of ligand precursors and complexation conditions allowed us to obtain a full range of intriguing PdII complexes including normal and abnormal carbene complexes, and zwitterionic palladalactam and CC-type palladacycles by means of A–H bond (A = N, C) activations.

We used time-resolved optical waveguide spectroscopy(OWGS) to in-situ measure visible absorption spectrum for methylene blue(MB) adsorbed on a hydrophilic glass waveguide from an aqueous solution containing proteins such as bovine serum albumin(BSA) and hemoglobin(Hb).The competitive adsorption of MB and the protein was detected at a solution pH lower than the isoelectric point of the protein.Since the competitive adsorption behavior of MB and the protein is very sensitive to the protein concentration,the protein content in the mixed solution was readily determined by time-resolved OWGS.In addition,a kinetic equation for the competitive adsorption of the two molecules was deduced based on the Langmuir adsorption isotherm.The best fit of the measured time course of the absorbance with the theoretical kinetic equation reveals that the number of MB molecules adsorbed on the surface exponentially decreases with time after reaching a maximum.A quasi-linear relationship between the fitting parameters and the protein concentration was also obtained.

A phytochemical study was performed on Arundina graminifolia (D.Don) Hochr. by silica gel column and semi-preparative HPLC, and ten stilbenoids were obtained. Their structures were elucidated by NMR and MS spectra and identified as 7-hydroxy-2,4-dimethoxy-9,10-dihydrophenanthrene (1), 4,7-dihydroxy-2-methoxy-9,10-dihydrophenanthrene (2), 2,7-dihydroxy-4-methoxy-9,10-dihydrophenanthrene (3), 3,3'-dihydroxy-5-methoxy-bibenzyl (4), 7-hydroxy-2,8-dimethoxy-phenanthrene-1,4-dione (5), 7-hydroxy-2,10-dimethoxy-phenanthre-ne-1,4-dione (6), 7-dihydroxy-2-methoxy-9,10-dihydrophenanthrene-1,4-dione (7), 7-hydroxy-2-methoxy-phenanthrene-1,4-dione (8), 7-hydroxy-1-(p-hydroxybenzyl)-2,4-dimethoxy-9,10-dihydroxy-phenanthrene (9), 2,7-dihydroxy-1-(p-hydroxybenzyl)-4-methoxy-9,10-dihydroxy-phenanthrene (10). Compounds 5 and 6 were isolated from this plant for the first time. The isolated compounds were examined for their anti-hepatic fibrosis activity against HSC-T6 cells in vitro. The results showed that compounds 4 and 5 exhibited moderate growth inhibitory effects with IC50 61.9 μg/mL and 52.7 μg/mL, respectively.

Optical waveguide(OWG) absorption spectroscopy makes use of an evanescent field to detect the polarized absorption spectra of sub-monomolecular adlayers.This technique is suitable for the investigation of adsorption kinetics at the solid/liquid interface of dyes,pigments,fluorescent molecules,quantum dots,metallic nanoparticles,and proteins with chromophores.In this work,a time-resolved optical waveguide spectrometer was constructed using a tungsten-halogen lamp,a prism-coupled thin-film glass waveguide,and a charge-coupled device(CCD) spectral analyzer.The adsorption properties of rhodamine 6G(R6G) and methylene blue(MB) were investigated using this apparatus.By comparing the transverse electric(TE) and transverse magnetic(TM) polarized absorption spectra,the R6G molecules were found to adsorb onto the glass surface as monomers and dimers while MB adsorbed mostly as high-order aggregates.The average orientation angles of the adsorbed dye molecules were also estimated.

Acceleration of gas hydrate formation is important in preventing coal and gas outbursts and is based on a hydration mechanism. It becomes therefore necessary to investigate the effect of surfactants, acting as accelerants for hydrate formation, on induction time. We experimented with three types of a Tween solution with equal concentrations of 0.001 mol/L (T40, T40/T80 (1:1), T40/T80 (4:1)). By means of visual experimental equipment, developed by us, we measured generalized induction time using a Direct Observation Method. The experimental data were analyzed combined with a mass transfer model and a hydrate crystal nuclei growth model. Our major conclusions are as follows: 1) solubilization of surfactants produces supersaturated gas molecules, which promotes the mass transfer from a bulk phase to hydrates and provides the driving force for the complexation between host molecules (water) and guest molecules in a gas hydrate formation process; 2) when the solution of the surfactant concentration exceeds the critical micelle concentration (CMC), the surfactant in an aqueous solution will transform to micelles. Most of the gas molecules are bound to form clusters with water molecules, which promotes the formation of crystal nuclei of gas hydrates; 3) the surfactant T40 proved to have more notable effects on the promotion of crystal nuclei formation and on shortening the induction time, compared with T40/T80 (1:1) and T40/T80 (4:1).

Formation of particles in a H2O2 counterflow diffusion flame doped with SiH4 or SiCl4 was investigated. When SiH4 is used as precursor, the species that nucleate in the flame depend on the SiH4 concentration as well as on the flame temperature. At low SiH4 concentrations and/or when a high-temperature flame is used, SiO2 is the species that nucleates. At high SiH4 concentrations and/or when a low-temperature flame is used, nucleation of SiOx (x = 0 and/or 1) in addition to SiO2 is believed to occur in the flame. When SiCl4 is used as precursor, SiO2 is the species that nucleates under all the experimental conditions studied here. Laser light scattering and extinction measurements indicate a specific region in the flame where growth of the particles by coagulation occurs, and the particles were always amorphous. When SiH4 is used as precursor, most of the particles are in the form of agglomerate of small particles (mostly 20–40 nm diameter) with some larger, spherical particles (mostly 80–150 nm diameter). When SiCl4 is used as precursor, the particles are all agglomerates of small particles (mostly 20–30 nm diameter). When SiH4 is used as precursor, a second flame, orange in color, appears below the H2O2 flame when the SiH4 concentration is increased beyond a certain value. This orange flame cannot be ascribed to radiation from SiO2 particles and is suspected to be due to SiOx particles.

Whitefly is a serious pest of chili pepper that could cause direct damage on the plant or serve as carrier of viral diseases. A study was conducted at the experimental farm of the Crop and Ecosystem Management Unit of AVRDC-The World Vegetable Center in Tainan, Taiwan, to evaluate the effects of nylon net as physical barrier and pyriproxyfen, an insect growth regulator (IGR), alone or in combination on controlling whitefly and yield of chili pepper. The experiments were laid-out in a randomized complete block design with three replications. The treatments were employed over an open field crop with the crop row covered with nylon net mesh #32 or #50 with or without pyriproxyfen applied at recommended rate. Results revealed that nylon mesh #50 was effective in excluding whiteflies compared to nylon mesh #32. Pyriproxyfen also reduced the number of whitefly count. However, based on a total of five harvests, yield decreased by 27% and 42% under nylon net barrier #50 and #32, respectively, compared to open field cultivation. Plants grown under nylon net were significantly taller in length and had higher leaf area index, or leaf and stem dry matter content but lower the fruit dry matter content.