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Intervertebral disc degeneration (IVDD) is a general disorder that results in low back pain and disability among many affected individuals. However, the current treatments for IVDD are limited to relieving the symptoms but do not solve the fundamental issue. In this study, the role of USP14 in mediating the activation of the NLRP3 inflammasome and the pyroptosis of AF cells from IVDD patients is determined in vitro, and gain- and loss-of-function assays of USP14 and the NLRP3 inflammasome are conducted. Pyroptosis of AF cells is detected by flow cytometry. The inflammatory cytokines (IL-1β and IL-18) and protein levels of NLRP3, active Caspase-1, Aggrecan, MMP3 and ADAMTS-5 are determined by ELISA and western blot analysis, respectively. The correlation between USP14 and NLRP3 is measured by coimmunoprecipitation and ubiquitination analysis. Upregulation of USP14 is accompanied by increased level of the NLRP3 inflammasome in AF cells from IVDD patients; furthermore, a positive correlation between them is observed. USP14 knockdown inhibits pyroptosis in AF cells by inducing ubiquitination of NLRP3, while overexpression of USP14 has the opposite effect, which is inhibited by the NLRP3 inflammasome inhibitor INF39. USP14 exerts its positive regulatory effect on AF cell pyroptosis by modulating the NLRP3/Caspase-1/IL-1β and IL-18 signaling axes.

Graphene has been extensively explored to enhance functional and mechanical properties of metal matrix nanocomposites for wide-range applications due to their superior mechanical, electrical and thermal properties. This article discusses recent advances of key mechanisms, synthesis, manufacture, modelling and applications of graphene metal matrix nanocomposites. The main strengthening mechanisms include load transfer, Orowan cycle, thermal mismatch, and refinement strengthening. Synthesis technologies are discussed including some conventional methods (such as liquid metallurgy, powder metallurgy, thermal spraying and deposition technology) and some advanced processing methods (such as molecular-level mixing and friction stir processing). Analytical modelling (including phenomenological models, semi-empirical models, homogenization models, and self-consistent model) and numerical simulations (including finite elements method, finite difference method, and boundary element method) have been discussed for understanding the interface bonding and performance characteristics between graphene and different metal matrices (Al, Cu, Mg, Ni). Key challenges in applying graphene as a reinforcing component for the metal matrix composites and the potential solutions as well as prospectives of future development and opportunities are highlighted.

Non-coding RNAs (ncRNAs) play essential roles in plants by modulating the expression of genes at the transcriptional or post-transcriptional level. In recent years, ncRNAs have been recognized as crucial regulators for growth and development in forest trees, and ncRNAs that respond to various abiotic stresses are now under intense study. In this review, we summarized recent advances in the understanding of abiotic stress-responsive microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and circular RNAs (circRNAs) in forest trees. Furthermore, we analyzed the intersection of miRNAs, and epigenetic modified ncRNAs of forest trees in response to abiotic stress. In particular, the abiotic stress-related lncRNA/circRNA–miRNA–mRNA regulatory network of forest trees was explored.

miRNAs are endogenous non-coding small RNAs with important regulatory roles in stress responses. Nitrogen (N) is an indispensable macronutrient required for plant growth and development. Previous studies have identified a variety of known and novel miRNAs responsive to low N stress in plants, including Populus. However, miRNAs involved in the cleavage of target genes and the corresponding regulatory networks in response to N stress in Populus remain largely unknown. Consequently, degradome sequencing was employed for global detection and validation of N-responsive miRNAs and their targets. A total of 60 unique miRNAs (39 conserved, 13 non-conserved, and eight novel) were experimentally identified to target 64 mRNA transcripts and 21 precursors. Among them, we further verified the cleavage of 11 N-responsive miRNAs identified previously and provided empirical evidence for the cleavage mode of these miRNAs on their target mRNAs. Furthermore, five miRNA stars (miRNA*s) were shown to have cleavage function. The specificity and diversity of cleavage sites on the targets and miRNA precursors in P. tomentosa were further detected. Identification and annotation of miRNA-mediated cleavage of target genes in Populus can increase our understanding of miRNA-mediated molecular mechanisms of woody plants adapted to low N environments.

Influenza A virus is a successful parasite and requires host factors to complete its life cycle. Prop5 is an antisense oligonucleotide, targeting programmed cell death protein 5 (PDCD5). In this study, we tested the antiviral activity of prop5 against mouse-adapted A/FM/1/47 strain of influenza A virus in a mouse model. Prop5 intranasally administered the mice at dosages of 10 and 20 mg/kg/d at 24 h and 30 min before infection, provided 80% and 100% survival rates and prolonged mean survival days in comparison with influenza virus-infected mice (both p < 0.01). Moreover, viral titres in mice pretreated with prop5, at dose of 10 and 20 mg/kg/d, had declined significantly on day two, four, and six post-infection compared with the yields in infected mice (p < 0.05 or p < 0.01); lung index in mice pretreated with prop5 (20 mg/kg/d) had been inhibited on day six post-infection (p < 0.05). Western blotting and immunohistochemistry showed that prop5 could down-regulate the PDCD5 protein expression levels in lung tissues of infected mice. These data indicate that antisense oligonucleotide prop5 is a promising drug for prophylaxis and control influenza virus infections and provides an insight into the host-pathogen interaction.

Numerous studies have shown that explosive sequence loads can cause serious damage to underwater vehicles, especially the bubble surge in the later stage of the explosion, which poses a huge threat to the internal structure of the vehicle. This study explores the damage characteristics of cylindrical shell structures under complete sequence loads based on the Arbitrary Lagrangian–Eulerian (ALE) method. By conducting experiments on the surge characteristics near the damaged plate under explosive action and comparing them with numerical results, the effectiveness of the method is verified. Subsequently, the damage characteristics of single- and double-layered cylindrical shell structures under underwater explosion sequence loads (shock waves, bubbles, surges) were explored, and the failure modes of cylindrical shell structures under various loads were summarized. The results indicate that the damage of shock waves to single-layer cylindrical shell structures is most severe at a blast distance of 0.5 m. For double-layer cylindrical shells, increasing the blast distance will reduce the impact of bubble surge on the pressure-resistant shell. The stress and strain in the central area of the pressure-resistant shell also decrease, and the deflection and Z-direction velocity also decrease accordingly. This study laid the foundation for enhancing the impact resistance of underwater vehicles.

Droplets oscillating on vibrating substrates are very interesting scientifically, with applications such as anti-icing, droplet transportation, and measuring dynamic surface tension. Reported here are the dynamics of droplets with different volumes on a vibrating smooth surface infused with liquid of different viscosities. The movement of the three-phase droplet contact line is used to quantify the droplet dynamics, and it is found that this movement is linearly proportional to the amplitude of the substrate and inversely proportional to the viscosity of the liquid infused therein. When the substrate viscosity is relatively low, the droplet volume also affects the contact-line movement. Scaling laws for the contact-line movement are derived involving the Ohnesorge number and the reciprocal of the capillary number. Also elucidated is the relationship between the resonance frequency and the substrate viscosity, and the characteristic droplet morphology under different substrate viscosities is extracted to describe the contact-line movement. Interestingly, the substrate viscosity is controlled in an innovative way to achieve almost the same contact-line movement on the present surface as on superhydrophobic and hydrophilic surfaces. [ABSTRACT FROM AUTHOR]