Antiviral activity of the HSP90 inhibitor VER-50589 against enterovirus 71.

Enterovirus 71 (EV71) is the major pathogen responsible for hand, foot, and mouth disease (HFMD) outbreaks; to date, there is no specific anti-EV71 agent. HSP90 is a crucial host factor for the viral life cycle and an ideal therapeutic target for limiting viral proliferation. However, the specific role of HSP90 in EV71-related signaling pathways and anti-EV71 agents targeting HSP90 remains unclear. This study aimed to verify the role of HSP90 in signaling pathways involved in EV71 replication and investigate the antiviral effects of a small molecule of VER-50589, a potent HSP90 inhibitor, against EV71 both in vitro and in vivo. Viral plaque assay, western blotting, and qPCR results showed that VER-50589 diminished the plaque formation induced by EV71 and inhibited EV71 mRNA and protein synthesis. A single daily dose of VER-50589 treatment significantly improved the survival rate of EV71-infected mice (p < 0.005). Interestingly, VER-50589 also exhibits activities against a series of human enteroviruses, including Coxsackievirus B3 (CVB3), Coxsackievirus B4-5 (CVB4-5), Coxsackievirus B4-7 (CVB4-7), and Echovirus 11 (Echo11). EV71 infection activated the AKT and ERK signaling pathways, and phosphorylation of AKT and RAF/MEK/ERK was weakened by VER-50589 administration. Thus, VER-50589 exhibits robust antiviral activity by inhibiting HSP90 and mediating the AKT and RAF/MEK/ERK signaling pathways. Considering that there are no effective antivirals or vaccines for the prevention and cure of HFMD in a clinical setting, the development of an anti-EV71 agent would be a straightforward and feasible therapeutic approach.

PLX8394, a RAF inhibitor, inhibits enterovirus 71 replication by blocking RAF/MEK/ERK signaling.

Enterovirus 71 (EV71) poses a serious threat to human health, with scattered outbreaks worldwide. There are several vaccines against a few EV71 strains but no efficient drug for the treatment of EV71 infection. Therefore, it is urgent and of significance to develop anti-EV71 drugs. Here, we found that PLX8394, a RAF inhibitor, possesses high antiviral activity against EV71 in vitro, being superior to the traditional clinical drug ribavirin. Moreover, PLX8394 exhibits broad-spectrum antiviral activity against enteroviruses. Notably, in a suckling mouse model, PLX8394 provided a 70% protection rate for EV71-infected mice, reduced the viral load in liver and heart tissues, and relieved the inflammatory response. A mechanistic study showed that PLX8394 inhibited EV71 by suppressing the RAF/MEK/ERK signaling pathway. Thus, PLX8394 lays a foundation for the development of new drugs against EV71.

ML390 inhibits enterovirus 71 replication by targeting de novo pyrimidine biosynthesis pathway.

Enterovirus 71 (EV71), a small, single-stranded, positive-sense RNA virus belonging to the enterovirus genus in the family Picornaviridae, causes hand, foot, and mouth disease. Although EV71 seriously threatens to public health, no effective antiviral drugs are available for treating this disease. In this study, we found that ML390, a dihydroorotate dehydrogenase inhibitor, has potential anti-EV71 activity. ML390 dose-dependently inhibited EV71 replication with IC50 and selectivity index values of 0.06601 µM and 156.5, respectively. Supplementation with the downstream product orotate significantly suppressed the ability of ML390 to inhibit EV71 replication. Moreover, an adequate supply of exogenous uridine and cytosine suppressed the anti-EV71 activity of ML390. Thus, the antiviral activity of ML390 is mediated by the inhibition of the pyrimidine synthesis pathway. In an EV71-infected mouse model, ML390 reduced the load of EV71 in the brain, liver, heart, spleen, front legs, and hind legs, and significantly increased the survival rate of the mice infected by EV71. ML390 shows potential for the treatment of hand, foot, and mouth disease caused by EV71 infection.

Synthesis of Ti6Al4V/SrFHA Composites by Microwave-Assisted Liquid Phase Deposition and Calcination.

The feasibility of synthesis of Ti6Al4V/SrFHA (Ca9.37Sr0.63(PO4)6F2) composites via coating strontium and fluorine co-doped HA to Ti6Al4V substrate by microwave-assisted liquid phase deposition and calcination was evaluated, with a focus on the effect of the deposition temperature from 30 °C to 70 °C. The outcomes demonstrate that strontium and fluorine can be successfully doped into HA to form a SrFHA coating with modified micromorphology which is deposited on the alloy. When the deposition temperature was 50 °C, the coating with the largest uniform continuous SrFHA coverage was obtained. After calcination, the adhesion strength and Vickers microhardness of the Ti6Al4V/SrFHA composite increased from 0.68 MPa and 323 HV to 2.41 MPa and 329 HV, respectively, with a decrease in the water contact angle from 10.88° to 7.24°, exhibiting enhancement of both mechanical properties and wettability. Moreover, the composite obtained at the deposition temperature of 50 °C exhibited good bioactivity based on the simulate body fluid (SBF) test. On account of the above features primarily as a result of the combined effect of the co-doping of strontium and fluorine, high crystallinity of SrFHA, large surface roughness, and formation of the titanium oxide transition layer, the Ti6Al4V/SrFHA composite shows great potential in dental implantology.

Enrichment of heavy metals from spent printed circuit boards by microwave pyrolysis.

This study reports the enrichment behaviors of heavy metals, including copper, tin, lead and zinc, in the process of microwave pyrolysis of spent printed circuit boards (SPCBs). The SPCB had good microwave absorptivity. Under the optimal conditions of microwave power of 700 W, pyrolysis temperature of 400 °C, dwell time of 5 min, N2 gas flow rate of 1.2 L/min, and load mass of 5 g, the yield of pyrolyzed SPCB was 79.16%. The contents of copper, tin, lead, and zinc in the pyrolyzed SPCB were increased to 28.52 wt%, 7.15 wt%, 1.31 wt%, and 1.13 wt%, respectively, with the corresponding retention percentages of 99.98%, 85.89%, 92.59% and 82.06%. The loss of metals was attributed to volatilization of the elements, which was affected by metal discharge due to excitation of electrons in the metals under microwave irradiation. Little copper loss was found because of the difficult reaction between copper and hydrogen bromide and the very high temperature required by the volatilization of copper. Tin, lead and zinc were mainly volatilized in the form of their metal bromides, including SnBr4, ZnBr2, and PbBr2. By controlling the pyrolysis conditions and metal discharge induced in the microwave field, the metals could be effectively enriched for subsequent treatment with high efficiency.

Exploring potential proteins associated with cyclin B 3'UTR in Procambarus clarkii oocytes.

Cyclin B is a ubiquitous regulatory molecule and has been implicated in mitosis and meiosis in oocytes. Phenomenon that differ in the length of cyclin B 3'UTR in crustacean has attracted much attention, although molecular details are poorly understood. The study of 3'UTR-interacting proteins could yield much information in translational regulation and the mRNA localization process. Previous studies on crayfish suggested that the 3'UTR (1300 bp) probably contains the potential regulatory sequence/motifs such as CPEs and K-box et al. In present study, using pull-down assay coupled with mass spectrometry approach allowing us to explore the potential proteins associated with the 3'UTR. We finally identified four candidate proteins including Hspg 2, Vtg, eef1a and Tuba1a, which annotated as significant roles involved in cell differentiation, lipid transporter activity, and meiotic cell cycle process. The preliminary results will contribute to the advance in understanding the translational activation of cyclin B in oocyte maturation regulation in crustacean.

Long-term effects of post-fire restoration types on nitrogen mineralisation in a Dahurian larch (Larix gmelinii) forest in boreal China.

Fire is an important disturbance agent in Chinese boreal forests but the long-term effects of wildfires on soil nitrogen (N) net mineralisation rates (Rmin) in natural versus human-assisted restorations are not well understood. In this study, we analysed upper (0-10cm) and lower layer (10-20cm) soil samples from natural restoration and afforestation plots in a Dahurian larch (Larix gmelinii) forest in north-eastern China 29years after a mega fire disturbance. Our results showed that the soil inorganic N (NH4+-N and NO3--N) pool of the upper and lower layers of the regenerated plots remained significantly lower than in unburned control plots. This suggests that the effects of a high burn severity fire on soil N availability were still significant almost 30years after the event. Restoration type (natural restoration versus afforestation) also had significant effects on upper layer soil N availability; compared with afforestation, natural restoration was more beneficial for the accumulation of soil inorganic N and the recovery of Rmin after fire disturbance. Specifically, the concentration of inorganic N and the mean Rmin in upper layer soils in the natural restoration plots were approximately 41% greater and 3.6 times greater, respectively, than in the afforestation plots. The differences in soil N availability between the two restoration types were attributed to differences in soil water content (SWC), soil microbial biomass nitrogen (MBN), and the recovery of vegetation after the fire disturbance. Our study demonstrates that natural restoration has proved more successful than afforestation in countering soil N losses in boreal forests in China resulting from a high burn severity fire disturbance.

NMR-based global metabolomics approach to decipher the metabolic effects of three plant growth regulators on strawberry maturation.

Plant growth regulators (PGRs) are commonly used to regulate maturation in strawberry. Despite this, comprehensive assessments of the metabolomic effects of PGRs on strawberry maturation are lacking. In this study, a nuclear magnetic resonance-based approach, combined with multivariate and pathway analysis, was used to evaluate the regulatory effects of gibberellin, forchlorfenuron, and brassinolide, applied at two different maturation stages, on the expression of metabolites in strawberry. The results demonstrated that the PGRs differentially influenced metabolism, whether applied at the same or different maturation stages. Additionally, we also discovered that these different PGRs exhibited some similar metabolic trends when applied at the same growth period. Our findings validate the use of NMR-based metabolomics for identifying subtle changes in the expression of metabolites associated with PGR application.

Conditions Optimizing and Application of Laccase-mediator System (LMS) for the Laccase-catalyzed Pesticide Degradation.

A high capacity of laccase from Trametes versicolor capable of degrading pesticides has been revealed. The conditions for degrading of five selected pesticides including chlorpyrifos, chlorothalonil, pyrimethanil, atrazine and isoproturon with the purified laccases from Trametes versicolor were optimized. The results showed that the optimum conditions for the highest activity were pH at 5.0 and temperature at 25 °C. The best mediators were violuric acid for pyrimethanil and isoproturon, vanillin for chlorpyrifos, and acetosyringone and HBT for chlorothalonil and atrazine, respectively. The laccase was found to be stable at a pH range from 5.0 to 7.0 and temperature from 25 to 30 °C. It was observed that each pesticide required a different laccase mediator concentration typically between 4.0-6.0 mmol/L. In the experiment, the degradation rates of pyrimethanil and isoproturon were significantly faster than those of chlorpyrifos, chlorothalonil and atrazine. For example, it was observed that pyrimethanil and isoproturon degraded up to nearly 100% after 24 hours while the other three pesticides just reached up 90% of degradation after 8 days of incubation.