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Remifentanil is a potent, short-acting opioid analgesic drug that can protect tissues from ischemia and reperfusion injury though anti-inflammatory effects. However, the utility of remifentanil in liver regeneration after hepatectomy is not known. Using a 70% hepatectomy mouse model (PHx), we found that preconditioning animals with 4 μg/kg remifentanil enhanced liver regeneration through supporting hepatocyte proliferation but not through anti-inflammatory effects. These effects were also phenocopied in vitro where 40 mM remifentanil promoted the proliferation of primary mouse hepatocyte cultures. We further identified that remifentanil treatment increased the expression of β-arrestin 2 in vivo and in vitro. Demonstrating specificity, remifentanil preconditioning failed to promote liver regeneration in liver-specific β-arrestin 2 knockout (CKO) mice subjected to PHx. While remifentanil increased the expression of activated (phosphorylated)-ERK and cyclin D1 in PHx livers, their levels were not significantly changed in remifentanil-treated CKO mice nor in WT mice pretreated with the ERK inhibitor U0126. Our findings suggest that remifentanil promotes liver regeneration via upregulation of a β-arrestin 2/ERK/cyclin D1 axis, with implications for improving regeneration process after hepatectomy.

Zygophyllum xanthoxylum is a salt‐accumulating xerophytic species with excellent adaptability to adverse environments. Previous studies demonstrated that Z. xanthoxylum absorbs a great quantity of Na⁺ as an osmoregulatory substance under arid conditions. To investigate the nutritional status of Z. xanthoxylum in comparison with a typical glycophyte, Arabidopsis thaliana, seedlings were exposed to NaCl (50 mM for Z. xanthoxylum and 5 mM for A. thaliana), osmotic stress (–0.5 MPa), and osmotic stress combined with the NaCl treatment. Compared to the control, NaCl treatment or osmotic stress significantly increased Na⁺ concentration in leaves and roots of Z. xanthoxylum, but not of A. thaliana. Under osmotic stress, the addition of NaCl significantly increased Na⁺ concentration in leaves and roots of Z. xanthoxylum, resulting in improved biomass and tissue water content. However, such changes were not observed in A. thaliana. Compared to the control, K⁺ concentrations in leaves and roots remained unchanged in Z. xanthoxylum when exposed to osmotic stress, with or without additional 50 mM NaCl. In contrast, significant reductions in shoot K⁺ concentrations of A. thaliana were observed under osmotic stress alone or when combined with 5 mM NaCl. Moreover, NaCl alone or when combined with osmotic stress enhanced the accumulation of N, P, Fe, Si, Ca²⁺, and Mg²⁺ in Z. xanthoxylum, but did not cause such nutritional changes in A. thaliana. Compared to the glycophyte A. thaliana, Z. xanthoxylum could accumulate Na⁺ and maintain the stability of nutritional status at a relatively constant level to cope with drought stress.

The Qinghai-Tibet Plateau, with its high elevation and extreme climate, is a transport artery for a crude oil-importation pipeline in China. However, limited information is available regarding the effect of petroleum hydrocarbon (PH) contamination on soil bacterial diversity. Variations in the bacterial structure and composition after PH pollution were investigated by a combination of artificial simulated pollution and high-throughput DNA sequencing. The results demonstrated that the biodiversity of engine oil-contaminated soil samples was higher than that of diesel oil-contaminated soil samples, and 7 genera were identified from indigenous bacteria as potential oil degraders, including Sulfuritalea, Sphingomonas, Alkanindiges, Rhodococcus, Nocardioides, Rhodoplanes, and Actinobacteria_norank. We present a detailed profile of soil bacteria succession under different oil-pollution conditions, which may help in future studies of in-situ bioremediation in this region.

We demonstrate an efficient high power and high brightness yellow-green 556-nm laser generated from second harmonic generation (SHG) of a master oscillator power amplifier (MOPA) laser system at 1112 nm. The oscillator was a pulsed laser diode (LD) pumped and Q-switched Nd:YAG laser at 1112 nm operated at TEM00 mode with an average output power of 35 W, providing 200-μs long macropulses and constituting 700-ns micropulses. The seed laser was amplified by two LD side-pumped Nd:YAG amplifiers and the MOPA system delivered a maximum output power of 78 W. Using a type-I phase-matching lithium triborate nonlinear crystal, the SHG maximum output power of 48 W was obtained at 556 nm with a conversion efficiency as high as 61.5%. The beam quality factor was measured to be M2 = 1.53 and the corresponding brightness was as high as 6.63 × 109 W/cm2·sr.

Wire drawing is a common used process to reduce the diameter of a small rod or a wire. The parameters of drawing die design such as die angle, bearing length, entrance fillet, and the drawing ratio of each pass are crucial to control the quality of a drawn wire. Taguchi method was adopted to optimize the drawing die geometry design. The lubrication conditions were taken into consideration to observe the effect of friction on the dimension accuracy of the drawn wires. The optimum combination of the drawing die design using 20% of reduction ratio is semi die angle 9 degrees, bearing length 1.2mm and entrance fillet 0.4mm. Two types of aluminum alloy 1070 and 1050 were tested using lubricants sodium sulfide (Na2S), graphite, and drawing oil, respectively. The lubrication effect of sodium sulfide is the best to achieve the lowest drawing load. The lubricant Na2S had the best performance in terms of lowest maximum drawing force for both of A1050 and A1070. The final diameters of the drawn wires were very close to the specification 4.0 mm. The CAE simulations were able to find the optimum design of die. The designed drawing machine was capable of carrying out the experiments and obtains consistent results.

The editorial office would like to draw reader's attention to an error occurring in the publication by Wang et al. · Under drought conditions NaCl improves the nutritional status of the xerophyte Zygophyllum xanthoxylum but not of the glycophyte Arabidopsis thaliana · pp. 597–606 · Volume 182 · Number 4 · August 2019 that we like to apologize for. 1. Figure : (Figure presented.) Fe concentration of Z. xanthoxylum (a) and A. thaliana (b) under different treatments (C, O, S, O+S) for 72 h. Control (C), osmotic stress (O) (–0.5 MPa osmotic potential induced by sorbitol), salt treatment (S) (50 mM NaCl for Z. xanthoxylum and 5 mM NaCl for A. thaliana), and osmotic stress with corresponding concentrations of NaCl (O+S) (total osmotic potential –0.5 MPa). Values are means ± SE (n = 8) and bars represent SE. Columns labelled different letters indicate significant differences at P < 5% (Duncan's test). 2. Figure : (Figure presented.) Si concentration of Z. xanthoxylum (a) and A. thaliana (b) under different treatments (C, O, S, O+S) for 72 h. Control (C), osmotic stress (O) (–0.5 MPa osmotic potential induced by sorbitol), salt treatment (S) (50 mM NaCl for Z. xanthoxylum and 5 mM NaCl for A. thaliana), and osmotic stress with corresponding concentrations of NaCl (O+S) (total osmotic potential –0.5 MPa). Values are means ± SE (n = 8) and bars represent SE. Columns labelled different letters indicate significant differences at P < 5% (Duncan's test). These changes do not affect the conclusions mentioned in the paper.

UNLABELLED PREMISE OF THE STUDY Food crops of tropical origins, such as rice, are often cultivated in areas with suboptimal temperature regimes. The rice phytochrome B-deficient mutant (phyB) is tolerant of chilling temperatures compared with the wild type (WT) under low irradiance, and unsaturated fatty acids (USFAs) of membrane lipids have been shown to play an important role in chilling resistance. However, the relationship between phytochrome B and membrane lipids has not been empirically investigated. • METHODS We assessed various photosynthesis indexes in phyB and WT rice: chlorophyll content, maximal photochemical efficiency (Fv/Fm) of photosystem II (PSII), the quantum yield of PSII electron transport (ΦPSII), the percentage of oxidizable P700 (P700), nonphotochemical quenching (NPQ), and the de-epoxidized ratio of xanthophyll cycle (A+Z)/(V+A+Z). We also analyzed the ultrastructure and fatty acid desaturases (FADs) and glycerol-3-phosphate acyltransferase (GPAT) genes of the chloroplasts using transmission electron microscopy and real-time PCR. • RESULTS After a chilling treatment of 24 h, chloroplast damage and USFA content reduction were more severe in the WT than in the phyB mutant. Genes involved in the synthesis of USFAs in membranes such as FADs and GPAT were more stable in phyB than in WT. Chlorophyll content, Fv/Fm, ΦPSII, and P700 decreased more slowly under chilling stress and recovered more rapidly under optimal conditions in phyB than in WT. The (A+Z)/(V+A+Z) and NPQ increased more rapidly in phyB than in the WT after 24 h of chilling treatment. • CONCLUSIONS Phytochrome B deficiency in rice with more stabilized chloroplast structure and higher USFA content in membrane lipids could alleviate chilling-induced photoinhibition.

The recretohalophyte with specialized salt-secreting structures including salt glands and salt bladders can secrete salt from their bodies and easily adapt themselves to many kinds of salt habitats. Salt glands and salt bladders, arose from dermatogen cells, are excretory organs specially adapted for dealing with ionic homeostasis in the cells of recretohalophytes. The main function of salt glands or salt bladders is to secrete excess ions that invade the plant. The structures of salt glands or salt bladders differ among plant species. In addition to structural differences, salt glands also differ in their secretion abilities. In this review, we mainly focus on recent progress in the mechanism of salt excretion of salt glands and salt bladders, and in particular, emphasize the vesicle-mediated secretion systems from the vacuole to the plasmalemma and the possibly involved membrane-bound translocating proteins for salt secretion of plant gland secretory cell.

Sulfides and volatile organic sulfur compounds (VOSc) in water are not only malodorous but also toxic to humans and aquatic organisms. They cause serious deterioration in the ecological environment and pollute drinking water sources. In the present study, a source water reservoir--Zhoucun Reservoir in East China--was selected as the study site. Through a combination of field monitoring and in situ release experiments of sulfides, the characteristics of seasonal variation and distribution of sulfides and VOSc in the reservoir were studied, and the cause of the sulfide pollution was explained. The results show that sulfide pollution was quite severe in August and September 2014 in the Zhoucun Reservoir, with up to 1.59 mg·L(-1) of sulfides in the lower layer water. The main source of sulfides is endogenous pollution. VOSc concentration correlates very well with that of sulfides during the summer, with a peak VOSc concentration of 44.37 μg·L(-1). An installed water-lifting aeration system was shown to directly oxygenate the lower layer water, as well as mix water from the lower and the upper layers. Finally, the principle and results of controlling sulfides and VOSc in reservoirs using water-lifting aerators are clarified. Information about sulfides and VOSc fluctuation and control gained in this study may be applicable to similar reservoirs, and useful in practical water quality improvement and pollution prevention.

Ascorbate–glutathione (AsA–GSH) cycle is an important component of the scavenging system for reactive oxygen compounds in plants. The member of this pathway involves the antioxidants: AsA, GSH and the antioxidatnt enzymes such as ascorbate peroxidase (APX), monodehydroascorbate reductase (MDAsAR), dehydroascorbate reductase (DAsAR) and glutathione reductase (GR). APX and GR are the key enzymes of the AsA–GSH cycle. APX utilizes AsA as the electron donor reducing H2O2 to water, and prevents the accumulation of a toxic level of H2O2 in photosynthetic organisms under stress conditions. GR converts oxidized glutathione (GSSG) to GSH using NAD(P)H as an electron donor. And thus a highly ratio of GSH/GSSG and AsA/DAsA is maintained at the intracellular level by this reaction during oxidative stress. In general, APX and GR activity have been shown to increase in various plant species under different stress conditions. Transgenic plants showed that APX and GR play an important role in providing resistance to oxidative stress caused by diferent stressors such as paraquat, methyl viologen, ozone, drought, heavy metals, high light, salinity, and chilling. In this review, recent progress in research on APX, GR and stress tolerance will be discussed.

Salt stress can induce ionic stress and osmotic stress in plant cells. A direct result of these primary effects is the enhanced accumulation of reactive oxygen species (ROS) that are harmful to plant cells at high concentrations. To cope with the oxidative stress resulting from the ROS, higher plants have developed a complex scavenging system including enzymatic and non-enzymatic ( antioxidants) system. In plant cells, specific ROS producing and scavenging systems are found in different organelles such as chloroplasts, mitochondria, and peroxisomes; and the ROS-scavenging pathways from different cellular compartments are coordinated. Relatively low levels of ROS can be used for signaling molecules to control abiotic stress responses. Coordinated work of ROS-scavenging pathways from different