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Mercury (Hg) is a heavy metal widely distributed in ecological environment, poisoning the immune system of humans and animals. Selenium (Se) is an essential microelement and selenoproteins involved in the procedure of Se antagonizing organ toxicity induced by heavy metals. The aim of this research was to investigate the changes of gene expression profile of selenoproteins induced by mercuric chloride (HgCl2) in chicken spleen lymphocytes. We established cytotoxicity model of chicken spleen lymphocytes by HgCl2 exposure, the messenger RNA (mRNA) expression levels of 25 selenoproteins in spleen lymphocytes were analyzed by real-time quantitative PCR (qPCR), and the gene expression pattern of selenoproteins was revealed by principal component analysis (PCA). The results showed that the mRNA expression levels of 13 selenoproteins (GPX3, GPX4, TXNRD2, TXNRD3, DIO2, SELENOS, SELENON, SELENOT, SELENOO, SELENOP, SELENOP2, MSRB1, and SEPHS2) were decreased in HgCl2 treatment group, and there was strong positive correlation between these selenoproteins and component 1 as well as component 2 of the PCA. At the same time, the protein expression levels of GPX4, TXNRD1, TXNRD2, SELENOM, SELENOS, and SELENON were detected by Western blotting, which were consistent with the changes of gene expression. The results showed that the expression levels of selenoproteins were aberrant in response to HgCl2 toxicity. The information presented in this study provided clues for further research on the interaction between HgCl2 and selenoproteins, and the possible mechanism of immune organ toxicity induced by HgCl2.

Kidney is a primary target organ for mercuric chloride (HgCl2) toxicity. Selenium (Se) can exert antagonistic effect on heavy metals–induced organ toxicity by regulating the expression of selenoproteins. The objective of this study was to investigate the effect of HgCl2 on the gene expression of selenoproteins in chicken kidney. Sixty male Hyline brown chickens were randomly and evenly divided into two groups. After acclimatization for one week, chickens were provided with the standard diet as well as non-treated water (CON group), and standard diet as well as HgCl2-treated water (250 ppm, HgCl2 group). After seven weeks, kidney tissues were collected to examine the mRNA expression levels of 25 selenoproteins genes and protein expression levels of 4 selenoproteins. Moreover, correlation analysis and principal component analysis (PCA) were used to analyze the expression patterns of 25 selenoproteins. The results showed that HgCl2 exposure significantly decreased the mRNA expression of Glutathione peroxidase 1 (GPX1), GPX4, Thioredoxin reductase 2 (TXNRD2), Iodothyronine deiodinase 1 (DIO1), Methionine-Rsulfoxide reductase 1 (SELR), 15-kDa selenoprotein (SEP15), selenoprotein I (SELI), SELK, SELM, SELN, SELP, SELS, SELT, SELW, and SEPHS2. Meanwhile, HgCl2 exposure significantly increased the mRNA expression of GPX3, TXNRD1, and SELU. Western blot analysis showed that the expression levels of GPX3, TXNRD1, SELK, and SELN were concordant with these mRNA expression levels. Analysis results of selenoproteins expression patterns showed that HgCl2-induced the main disorder expression of selenoproteins with antioxidant activity and endoplasmic reticulum resident selenoproteins. In conclusion, selenoproteins respond to HgCl2 exposure in a characteristic manner in chicken kidney.

A left-handed helical poly(phenyl isocyanide) bearing a norbornene unit and a Pd(II) complex on each terminus was prepared. The norbornene terminus was core cross-linked with a bisnorbornene linker via ring-opening metathesis polymerization (ROMP), yielding a star polymer carrying left-handed helical arms decorated with Pd(II) units at the exterior. The optical activities of the helical arms were maintained after the cross-linking reaction. The Pd(II) units on the surface of the star polymer were chain extended with a new phenyl isocyanide bearing three hydrophilic triethylene glycol monomethyl chains, which afforded an amphiphilic star block copolymer carrying helical arms. Such a star block copolymer showed excellent thermoresponsiveness with the lower critical solution temperature (LCST) around 55 °C. This optically active and thermoresponsive star polymer can enantioselectively capture the S-enantiomer of racemic methyl benzyl alcohol solution at a temperature lower than the LCST and precipitated when...

Mercuric chloride (HgCl

Mercury (Hg) is a persistent environmental and industrial pollutant that accumulated in the body and induces oxidative stress and inflammation damage. Selenium (Se) has been reported to antagonize immune organs damage caused by heavy metals. Here, we aimed to investigate the prevent effect of Se on mercuric chloride (HgCl

Mercuric chloride (HgCl

Mercuric chloride (HgCl

In this work, air-stable palladium(II) catalysts bearing bidentate phosphine ligands were designed and prepared, which could initiate fast and living polymerizations of various diazoacetate monomers under mild conditions. The polymerization afforded the desired polymers in high yields with controlled molecular weights ( M

In this paper, the facile synthesis of hybrid Fe3 O4 magnetic nanoparticles carrying helical poly(phenyl isocyanide) (PPI) arms via both "grafting from" and "grafting onto" strategies is reported. First, alkyne-Pd(II) catalysts are anchored onto the surface of the Fe3 O4 magnetic nanoparticle, which promote the polymerization of enantiopure phenyl isocyanide, affording the expected hybrid magnetic nanoparticle with Fe3 O4 in core and helical PPI as arms. The nanoparticle also exhibits highly optical activity due to the excess of one-handed helicity of the PPI arms. Moreover, the hybrid magnetic nanoparticle can be alternatively synthesized via "grafting onto" strategy. A triethoxysilanyl-terminated single handed helical PPI bearing l-alanine ester pendants is prepared and grafted onto the surface of Fe3 O4 nanoparticle. The generated hybrid magnetic nanoparticles show both magnetic character and optical activity. Taking advantage of these properties, they can be used in enantioselective crystallization of racemic threonine. The enantiomeric excess (ee) of the induced crystals is up to 93%. Moreover, the nanoparticles can be facilely recovered and recycle used for at least four times in enantioselective crystallization without significantly loss of its enantioselectivity.

Zr-based thin film metallic glass (TFMG), exhibiting the unique properties of good glass forming ability (GFA), corrosion resistance, and biocompatibility, can be applied in various novel fields of industries. An ultra-smooth surface is obtained with the TFMG coatings, which is beneficial to modify the work surface. Thus, TFMG can be extended to medical appliances, such as surgical blades and micro-surgery scissors. The aims of this study are to fabricate the Cu-containing Zr-based TFMG onto SUS304 plates and to investigate the surface physical properties and their antimicrobial effects. The chemical compositions of Zr–Cu–Ni–Al coatings are examined by a field emission electron probe micro-analyzer (FE-EPMA). The amorphous structures of all TFMG are characterized by the X-ray diffractometry. The surface properties are analyzed by an atomic force microscope (AFM) and a water contact angle goniometer for the 304 stainless steel substrate and Zr–Cu–Ni–Al TFMG. Liquid culture methods and plate counting methods are used to assess the antimicrobial performance of specimens. The antimicrobial rate against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) under the Japanese Industrial Standard JIS Z2801: 2000 is over 99%. The release of copper ion from TFMG specimen is determined by the inductively coupled plasma-mass spectrometer (ICP-MS) to evaluate the antimicrobial activity of Cu-containing Zr-based TFMG. The results show that the surface of SUS 304 stainless steel substrate can be modified with deposited Zr–Cu–Ni–Al TFMG, and their improved antimicrobial efficacy against those bacteria is attributed to their amorphous rough surface, hydrophobic properties and released copper ion. The TFMG developed in this study with adequate hardness, good adhesion ability and antimicrobial efficiencies can be used as a promising candidate to improve the surface properties of the medical appliances and also to reduce the possibility of nosocomial infection.

The aims of this study are to fabricate the Zr–Cu–Ni–Al thin film metallic glass (TFMG) on silicon substrates by DC magnetron sputtering with single target and to investigate the characteristics of coatings with various substrate temperatures. All the coatings exhibit similar structural and thermal properties, yet the hardness increases with processing temperature. It is demonstrated that amorphous matrix and cluster structure are slightly affected by the processing temperatures due to high cooling rate during deposition and superior glass-forming ability. Besides, atoms and clusters can acquire extra energy via heating substrate to stabilize each cluster, and the amount of free volume is reduced. Thus, the hardness increases with substrate temperature owing to the resistance to the shear band propagation. In summary, this study integrates the correlations among microstructure, thermal and mechanical properties, providing a convenient approach to tune TFMG coating performance.