Molecular characteristics and immune function of ubiquitin C-terminal hydrolase-L3 in Macrobrachium nipponense.

Ubiquitin C-terminal hydrolase-L3 (UCHL3) is a deubiquitinating enzyme involved in the repair mechanism of homologous recombinations of DNA double strand breaks (DBS). However, the role of UCHL3 in crustacean immune regulation has not been studied. In this experiment, we cloned and analyzed the expression profile of the UCHL3 gene from Macrobrachium nipponense (MnUCHL3). The obtained full-length cDNA of the MnUCHL3 transcript was 1192 bp, and it had a 687 bp open reading frame encoding a 228 amino acid protein, and the structure of UCHL3 is highly similar to that of other invertebrates. Real-time PCR results indicated that MnUCHL3 was expressed in all detected tissues, with the highest expression levels in the hepatopancreas, and the expression of MnUCHL3 in the gill and hepatopancreas was downregulated to different degrees within 48 h after the infection of viruses and bacteria. Furthermore, knockdown of MnUCHL3 expression by double-stranded RNA (dsRNA) injection in Aeromonas hydrophila-infected prawns increased prawn mortality and bacterial growth. In addition, overexpression of MnUCHL3 in HEK293T cells in vitro suggested that MnUCHL3 could activate the NF-κB signal path and the expression levels of NF-κB signaling cascade members and AMPs, exhibiting remarkable downregulation in the MnUCHL3-silenced group. The above experimental conclusions revealed that UCHL3 gene might be involved in the innate immune response to bacterial infection by regulating the synthesis of a series of AMPs, and these results might provide new insights into UCHL3 in invertebrates.

The Penetration-Explosion Effects of Differently Distributed Inactive/Active Composite Shaped Charge Jets.

An analysis of the penetration-explosion (PE) effects of four distributions of inactive/active composite jets shows that a well-designed inactive/active double-layer liner can promote composite jet damage. Penetration experiments were then carried out for shaped charge jets having a single inactive (Cu) liner or an inactive/active (Cu/Al) double-layer liner with variable liner height. The behaviors and firelight patterns of the different jets were captured by high-speed photography. The perforation, deformation area, and deflection were measured for each plate, showing that the Cu/Al jets have stronger PE effects. Numerical simulation shows that the tip of the composite jet generated from the full-height liner is only Cu, whereas for the other jet, from the double-layer liner, Cu is almost wrapped entirely by Al.

The CO2 absorption and desorption analysis of tri-solvent MEA + EAE + AMP compared with MEA + BEA + AMP along with "coordination effects" evaluation.

The slow kinetics of CO2 absorption and high energy cost of CO2 desorption were the main challenges for CO2 capture technology. To overcome these drawbacks, a novel tri-solvent MEA (monoethanolamine) + EAE (2-(ethylamino)ethanol) + AMP (2-amino-2-methyl-1-propanol) was prepared at different amine concentrations of 0.1 ~ 0.5 + 2 + 2 mol/L. The CO2 absorption and desorption experiments were conducted on MEA + EAE + AMP and their precursor MEA + EAE to evaluate the absorption-desorption parameters. Results demonstrated that the optimized concentrations of the bi-blend were 0.2 + 2 mol/L for absorption and 0.4 + 2 mol/L for desorption. For the tri-solvent, the optimized concentration was 0.2 + 2 + 2 mol/L, consistently for both abs-desorption sides. Compared with tri-solvent of MEA + BEA + AMP, MEA + EAE + AMP proved better in absorption but poorer in desorption, while its CO2 loading of operation line was 0.35 ~ 0.70 mol/mol, higher than that of 0.30-0.60 mol/mol MEA + BEA + AMP. These results led to another tri-solvent candidate of amine solvents in an industrial pilot plant.

Influence of outer membrane vesicles of Proteus mirabilis isolated from boar semen on sperm function.

This study focuses on the effect of outer membrane vesicles (OMVs) in gram-negative bacteria on boar sperm function during in vitro storage. In the 40 ejaculates collected from Guangzhong Black boar, six gram-negative bacterial species were detected by 16S rDNA sequencing, of which Proteus mirabilis was the main contaminating bacterium. The OMVs of P. mirabilis were isolated by gradient ultracentrifugation. To reveal the effect of OMVs on boar sperm, different OMV concentrations were added to the Modena medium during sperm storage at 17 °C. Even after 3 days of storage, it was noted that low OMV dose (<5 µg/mL) in the extender did not significantly reduce sperm quality as compared with that in the control semen samples; however, sperm motility and sperm morphology were significantly altered in the extender owing to a high OMV dose (>10 µg/mL). The relative ROS level successively increased with OMV dose in sperm samples and storage time. Meanwhile, OMVs dramatically elevated the mitochondrial potential of sperm. OMVs could bind with the sperm membrane to further influence the capacity of sperm-oocyte binding; they also increased the expression of LC3 and caspase 3 and decreased that of anti-apoptosis-related protein, Bcl2, in sperm. It was concluded that OMVs of P. mirabilis influenced the function of boar sperm by inducing sperm membrane reconstruction as well as autophagy and apoptosis of sperm.