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Background Age-related macular degeneration (AMD) may lead to irreversibly vision loss among aging populations. In this work, in an in vitro AMD cell model, we examined the expression and function of long non-coding RNA, Prader-Willi Region Non-Protein Coding RNA 2 (PWRN2) in injured human retinal pigment epithelial cells. Method ARPE-19 cell line was maintained in vitro and treated with multi-module stressful conditions, including hydrogen peroxide (H2O2) tert-butylhydroperoxide (t-BuOOH) and ultraviolet B (UVB). Multi-module-stressor-induced cell death was monitored by a viability assay, and PWRN2 expression by qRT-PCR. PWRN2 was either downregulated or upregulated in ARPE-19 cells. The effects of PWRN2 downregulation or upregulation on t-BuOOH-induced cell death, cellular apoptosis and mitochondrial injuries were then quantitatively evaluated. Results Multi-module stressful conditions induced cell death and PWRN2 upregulation in ARPE-19 cells in vitro. We created ARPE-19 subpopulations with either downregulated or upregulated PWRN2 expressions. Quantitative assays demonstrated that, PWRN2 downregulation effectively alleviated t-BuOOH-induced cell death, apoptosis and various-type of mitochondrial injuries. On the other hand, PWRN2 upregulation worsened t-BuOOH-induced cellular damages in ARPE-19 cells. Conclusion We demonstrated that downregulating PWRN2 protected multi-module-stressor-induced cell death, apoptosis and mitochondrial injuries in human retinal pigment epithelial cells, suggesting PWRN2 may be an active factor in human AMD.

The effects of Si content on the microstructure and yield strength of Al−(1.44−12.40)Si−0.7Mg (wt.%) alloy sheets under the T4 condition were systematically studied via laser scanning confocal microscopy (LSCM), DSC, TEM and tensile tests. The results show that the recrystallization grain of the alloy sheets becomes more refined with an increase in Si content. When the Si content increases from 1.44 to 12.4 wt.%, the grain size of the alloy sheets decreases from approximately 47 to 10 μm. Further, with an increase in Si content, the volume fraction of the GP zones in the matrix increases slightly. Based on the existing model, a yield strength model for alloy sheets was proposed. The predicted results are in good agreement with the actual experimental results and reveal the strengthening mechanisms of the Al−(1.44−12.40)Si−0.7Mg alloy sheets under the T4 condition and how they are influenced by the Si content.

Friction stir additive manufacturing (FSAM) can be potentially used for fabricating high-performance components owing to its advantages of solid-state processing. However, the inhomogeneous microstructures and mechanical properties of the build attributed to the complex process involving restirring and reheating deserve attention. This study is based on the previous research of the underwater FSAMed 7A04 aluminum alloy and adopts a quasi in situ experimental method, i.e., after each pass of the underwater FSAM, samples were taken from the build for microstructural observation to investigate the restirring and reheating effects on microstructural evolution during the underwater FSAM. Fine-grain microstructures were formed in the stir zone during the single-pass underwater FSAM. After restirring, the grain size at the bottom of the overlapping region decreased from 1.97 to 0.87 μm, the recrystallization degree reduced from 74.0% to 29.8%, and the initial random texture transformed into a strong shear texture composed of the C {110}. After reheating, static recrystallization occurred in the regions close to the new additive zones, increasing the grain size and recrystallization degree. This study not only revealed the microstructural evolution during the underwater FSAM but also provided a guideline for further optimization of the mechanical properties of the Al–Zn–Mg–Cu alloy build.

The effects of quenching in different ways following solid-solution treatment on properties and precipitation behaviors of 7050 alloy were investigated by transmission electron microscopy (TEM), scanning electron microscopy (SEM), selected area electron diffraction (SAED), hardness and electrical conductivity tests. Results show that after quenching in different ways, electrical conductivity of the alloy decreases rapidly in the first 48 h of natural aging. The electrical conductivity of 7050 alloy in natural aging state is determined by the size and density of GP zones, and the size of GP zones is the main factor. After natural aging for 70 d, the size of GP zones is 1.8–2.6 nm in matrix of the immersion quenched sample and it is 1.4–1.8 nm in matrix of both water mist and forced air quenched samples. After natural and artificial peak aging, the hardness of the water mist quenched sample is HV 193.6 and its electrical conductivity is 30.5% (IACS) which are both higher than those of the immersion quenched sample. Therefore, water mist quenching is an ideal quenching method for 7050 alloy sheets after solid-solution treatment.

The hepatitis C virus (HCV) subgenomic replicon is a valuable tool for studying virus replication and HCV drug development. Despite the fact that HCV genotype 1a (HCV1a) is the most prevalent genotype in the United States, few HCV1a reporter replicon constructs have been reported, and their replication capacities are not as efficient as those of HCV1b or 2a, especially in transient expression. In this study, we selected efficient HCV1a replicons and characterized the novel adaptive mutations derived from stable HCV1a (strain H77) replicon cells after G418 selection. These novel adaptive mutations were scored in NS3 (A1065V, C1073S, N1227D, D1431Y, and E1556G), NS4A (I1694T and E1709V), and NS4B (G1871C). The D1431Y mutation alone or combinations of other adaptive mutations introduced into the parental HCV1a replicon construct was observed to differentially enhance either transient or stable expression of replicon. In particular, two replicon mutants VDYG (A1065V, N1227D, D1431Y, and E1556G within NS3) and VDYGRG, VDYG with two additional adaptive mutations (NS4A-K1691R and NS4B-E1726G), displayed robust replication and exhibited no impairment in the susceptibility of replicon activity to various known HCV inhibitors.

According to inverse heat transfer theory, the evolutions of synthetic surface heat transfer coefficient (SSHTC) of the quenching surface of 7B50 alloy during water-spray quenching were simulated by the ProCAST software based on accurate cooling curves measured by the modified Jominy specimen and temperature-dependent thermo-physical properties of 7B50 alloy calculated using the JMatPro software. Results show that the average cooling rate at 6 mm from the quenching surface and 420–230 °C (quench sensitive temperature range) is 45.78 °C/s. The peak-value of the SSHTC is 69 kW/(m2·K) obtained at spray quenching for 0.4 s and the corresponding temperature of the quenching surface is 160 °C. In the initial stage of spray quenching, the phenomenon called “temperature plateau” appears on the cooling curve of the quenching surface. The temperature range of this plateau is 160–170 °C with the duration about 3 s. During the temperature plateau, heat transfer mechanism of the quenching surface transforms from nucleate boiling regime to single-phase convective regime.

This paper investigates how anticorruption measures affect corporate governance, especially the executive incentive mechanism. The results of empirical tests show that in the short term, alleviating corruption does not enhance executives incentive, however, it significantly escalates pay-performance sensitivity. It is also found reductions in executive incentive in state-owned companies are more salient than in non-state-owned companies. The suggestion is that anticorruption measures at firm level should be a long-term strategy and focus on state-owned companies. It provides a new perspective for understanding how anticorruption affects firm behavior and performance and for the literature on executive incentives with political intervention.

Dengue virus (DENV) is a global health problem that affects approximately 3.9 billion people worldwide. Since safety concerns were raised for the only licensed vaccine, Dengvaxia, and since the present treatment is only supportive care, the development of more effective therapeutic anti-DENV agents is urgently needed. In this report, we identified a potential small-molecule inhibitor, BP34610, via cell-based high-throughput screening (HTS) of 12,000 compounds using DENV-2 reporter viruses. BP34610 reduced the virus yields of type 2 DENV-infected cells with a 50% effective concentration (EC50) and selectivity index value of 0.48 ± 0.06 μM and 197, respectively. Without detectable cytotoxicity, the compound inhibited not only all four serotypes of DENV but also Japanese encephalitis virus (JEV). Time-of-addition experiments suggested that BP34610 may act at an early stage of DENV virus infection. Sequencing analyses of several individual clones derived from BP34610-resistant viruses revealed a consensus amino acid substitution (S397P) in the N-terminal stem region of the E protein. Introduction of S397P into the DENV reporter viruses conferred an over 14.8-fold EC90 shift for BP34610. Importantly, the combination of BP34610 with a viral replication inhibitor, ribavirin, displayed synergistic enhancement of anti-DENV-2 activity. Our results identify an effective small-molecule inhibitor, BP34610, which likely targets the DENV E protein. BP34610 could be developed as an anti-flavivirus agent in the future.

Microstructures of creep-aged 2524 (Al–4.3Cu–1.5Mg) aged at 170 °C with various stresses (0, 173 and 250 MPa) were studied on a creep machine. Ageing hardness curves under various stresses were plotted and the corresponding microstructures were characterized by transmission electron microscopy (TEM). The results show that the value of peak hardness is increased, while the time to reach the peak hardness is reduced under an external stress. Meanwhile, the length of S (Al 2 CuMg) phase is shorter and the number density of S phases is larger in the creep-aged alloy. The predominant contribution to the peak hardness can be ascribed to the GPB zones with an elastic stress.

The microstructure and overheating characteristics of the direct chill semicontinuous casting ingot of 7B04 high strength aluminum alloy, and those after industrial homogenization treatment and multi-stage homogenization treatments, were studied by differential scanning calorimetry(DSC), optical microscopy(OM) and scanning electron microscopy with energy dispersive X-ray spectroscopy(SEM-EDX). The results show that the microstructure of direct chill semicontinuous casting ingot of the 7B04 alloy contains a large number of constituents in the form of dendritic networks that consist of nonequilibrium eutectic and Fe-containing phases. The nonequilibrium eutectic contains Al, Zn, Mg and Cu, and the Fe-containing phases include two kinds of phases, one containing Al, Fe, Mn and Cu, and the other having Al, Fe, Mn, Cr, Si and Cu. The melting point of the nonequilibrium eutectic is 478 °C for the casting ingot of the 7B04 alloy which is usually considered as its overheating temperature. During industrial homogenization treatment processing at 470 °C, the nonequilibrium eutectic dissolves into the matrix of this alloy partly, and the remainder transforms into Al2CuMg phase that cannot be dissolved into the matrix at that temperature completely. The melting point of the Al2CuMg phase which can dissolve into the matrix completely by slow heating is about 490 °C. The overheating temperature of this high strength aluminum alloy can rise to 500–520 °C. By means of special multi-stage homogenization, the temperature of the homogenization treatment of the ingot of the 7B04 high strength aluminum alloy can reach 500 °C without overheating.

The texture evolution and lattice rotation in Al alloy 6111 with an initial {001} component during symmetrical and asymmetrical rolling were investigated by means of orientation distribution function(ODF). The results show that the as-rolled initial {001} orientation evolves into not only the copper orientation but also all the other orientations along the β fiber, including the brass orientation, by lattice rotation around special directions. Compared with the symmetrical rolling, the {001} component in the surface layer on the slower roller side evolves more quickly into the orientations along the β fiber during asymmetrical rolling, while that in the surface layer on the faster roller side evolves more slowly.

The binding model of cis -Ru II Cl 2 (DMSO) 3 (DMSO) ( cis -RDT, three out of the four DMSO's are S-bonded to the Ru, while the last one is O-bonded) with 5′-GMP and 5′-AMP in aqueous solution at physiological pH value were investigated by high-resolution 1 H and 31 P NMR. A 1 H NMR recognition probe, [ trans -en 2 Os(η-H 2 )](CF 3 SO 3 ) 2 , was used in order to verify further the results. 5′-GMP with cis -RDT formed two products, clearly indicating that the guanine N 7 and phosphate group bind to Ru II and form a chelate to the metal center; but binding of 5′-AMP to cis -RDT may only occur via the phosphate group.

Permeabilized rat kidney cells rapidly released glucose 6-phosphate dehydrogenase (G6PD) following stimulation with peptide growth factors (Stanton, R.C., Seifter, J.L., Boxer, D.C., Zimmerman, E., and Cantley, L. C. (1991) J. Biol. Chem. 266, 12442-12448). To evaluate the signal transduction pathways mediating release of G6PD, two cell lines transfected with wild type or mutant platelet-derived growth factor (PDGF) receptors (PDGFR) were studied using two permeabilization protocols. G6PD release was evaluated by enzyme activity and Western blot analysis. PDGF caused a significant increase in G6PD release in 1 min in cells transfected with wild type PDGFR. PDGF did not stimulate G6PD release in cells transfected with tyrosine kinase-deficient PDGFR. PDGF did not stimulate G6PD release in cells transfected with partially autophosphorylation-deficient PDGFR in which four known signaling proteins do not associate with the PDGFR. The PDGF-stimulated release of G6PD was partially restored in PDGFR mutants in which either phosphatidylinositol-3-kinase or phospholipase C gamma 1 could associate with the PDGFR. Lastly, there was no basal or PDGF-stimulated phosphorylation of G6PD. We conclude that release of G6PD: 1) requires intrinsic PDGFR tyrosine kinase activity; 2) requires PDGFR autophosphorylation; 3) is mediated by signaling proteins that associate with the PDGFR; 4) is not mediated by direct phosphorylation of G6PD.

Prolonged exposure of tissues to hormone agonists results in a subsequent reduction in the sensitivity of the tissue through a process known as desensitization. The desensitization response, either homologous or heterologous, has been shown to be correlated with receptor phosphorylation. Recently we have provided evidence that protein kinase C, when activated by a phorbol ester, regulates α1-adrenoceptor coupling to a G-protein. In the present study, the effects of epinephrine (10 μM) pretreatment on the binding behavior of the α1-adrenoceptor were determined from radioligand binding assays at 25° and 2°C. Pretreatment of tissues with epinephrine for 25 min moderately decreased [3H]prazosin binding by 12% (Bmax 121.5 fmol/mg) in comparison to control (139.3 fmol/mg) with no change in its affinity. The second consequence of desensiization by epinephrine is a decrease in the affinity of agonist binding to α1-adrenoceptors associated with uncoupling of the receptors from the G-protein. In control membranes, at 25°C, epinephrine defined two different affinity states of the receptor, viz. high affinity (KDH 16.5 nM, % RH 21) and low affinity (KDL 710 nM, % RL 79). The high affinity state formed at 25°C is stabilized by forming a ternary complex with a G-protein. Addition of guanylylimidodiphosphate (Gpp(NH)p) reduced the stability of this complex resulting in a loss of high affinity sites in control membranes. On the other hand, epinephrine treated membranes exhibited only a single class of low affinity agonist binding (KDH 659 nM) and further, Gpp(NH)p had no significant effect on binding. In low-temperature binding studies, both treated and untreated preparations exhibited a large proportion of sites (% RH 88 and 87) in the high affinity state indicating that receptors retain the ability to achieve a high affinity conformation, as established by the reduced temperature. Our results indicate that epinephrine desensitization includes a selective loss in the ability of G-proteins to stabilize a high affinity state of the α1-adrenoceptor. This effect of agonist preexposure, thus, resembles receptor/G-protein uncoupling described previously following protein kinase C activation.