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Abstract Coumarin forms an elite class of naturally occurring compounds that possess promising antiviral therapeutic perspectives. In the previous study, we designed and synthesized a coumarin derivative, 7-(4-benzimidazole-butoxy)-coumarin (BBC), to evaluate its antiviral activity on spring viraemia of carp virus (SVCV). In this study, our results show that BBC does not affect viral adhesion and delivery from endosomes to the cytosol, indicating BBC has no inhibitory activity in the early stage of viral infection. Further data are determined that BBC significantly declines SVCV-infected apoptosis and recovers caspase-3/8/9 activity. To reveal the pathway that affects Nrf2 translocation by BBC, we examine changes in protein kinase C (PKC) in EPC cells treated with BBC. We observe that BBC results in a higher phosphorylation of PKCα/β that is involved in the activation of erythroid 2-related factor 2 (Nrf2) phosphorylation to favor Nrf2 translocation to nucleus at 24 and 48 h. In addition, the results show that BBC also up-regulates both antiviral responses, heme oxygenase-1 (HO-1) expression and cellular IFN response. Overall, this mechanism of action provides a new therapeutic target for the treatment of SVCV infection, and these results suggest that treatment with BBC is effective in reducing SVCV infection and differently regulates SVCV-induced undesirable conditions. Highlights • BBC effectively inhibits SVCV replication in host cells. • BBC can enhance PKC phosphorylation to activate Nrf2 expression and translocation to nucleus. • BBC up-regulates heme oxygenase-1 (HO-1) expression in addition to cellular IFN response. [ABSTRACT FROM AUTHOR]

Abstract: The isolation of the vibration due to moving loads using pile rows embedded in a poroelastic half-space is investigated in this study. Based on Biot''s theory and integral transform method, the free field solution for a moving load applied on the surface of a poroelastic half-space and the fundamental solution for a harmonic circular patch load applied in the poroelastic half-space are derived first. Using Muki and Sternberg''s method and the fundamental solution for the circular patch load as well as the obtained free field solution for the moving load, the second kind of Fredholm integral equations in the frequency domain describing the dynamic interaction between pile rows and the poroelastic half-space is developed. Numerical solution of the frequency domain integral equations and numerical inversion of the Fourier transform yield the time domain response of the pile–soil system. Comparison of our results with some known results shows that our results are in a good agreement with existing ones. Numerical results of this study show that velocity of moving loads has an important impact on the vibration isolation effect of pile rows. The same pile row has a better vibration isolation effect for the lower speed moving loads than for the higher speed ones. Also, the optimal length of piles for higher speed moving loads is shorter than that for lower speed moving loads. Moreover, stiff pile rows tend to produce a better vibration isolation effect than flexible pile rows do. [Copyright &y& Elsevier]

Abstract: In this paper, Green''s function for an acoustic source within half-space seawater overlying a porous seabed is established. The half-space seawater is described using the Helmholtz equation, while the seabed is considered as a saturated porous medium and characterized by Biot''s theory. Green''s function of the half-space seawater has two components: the principal and complementary parts. The principal part of Green''s function is the solution for a conventional acoustic point source in an infinite medium, while the complementary part corresponds to the general solution of the Helmholtz equation for the half-space. Green''s function of the half-space seabed is obtained by solving Biot''s dynamic equations via the Hankel transform method. Using the continuity conditions at the interface between the seawater and the seabed, the closed-form Green''s functions for the seawater and the seabed in the frequency–wavenumber domain are determined. The frequency domain Green''s function is recovered by the inversion of the Hankel transform. A parametric study is carried out for Green''s function in the frequency domain, and a time domain example is presented in terms of frequency domain Green''s function. Numerical results show that the permeability of the porous seabed has very little influence on the response of the seawater, while Biot''s modulus has a pronounced influence on the wave field. [Copyright &y& Elsevier]

Dynamic response of an infinite beam resting on a layered poroelastic half-space subjected to moving loads is investigated in this study. The equivalent stiffness of the layered poroelastic half-space is obtained via the transmission and reflection matrices (TRM) method in the frequency wavenumber domain. Based on the obtained equivalent stiffness, the frequency wavenumber domain solution of the beam–half-space system is obtained by the compatibility condition between the beam and the half-space. The time domain solution for the beam and the layered half-space is obtained by means of the inverse Fourier transform method. Also, the influences of the load speed and material parameters of the poroelastic half-space on the responses of the beam as well as the layered half-space are investigated. In order to demonstrate the proposed method, some time–space domain examples and corresponding analysis are presented in the paper. [Copyright &y& Elsevier]

Abstract: The objective of this paper is to use Biot’s theory and the Johnson–Koplik–Dashen dynamic permeability model in wave field simulation of a heterogeneous porous medium. The Johnson–Koplik–Dashen dynamic permeability model was originally formulated in the frequency domain. In this paper, the time domain drag force expression of the model is expressed in terms of the shifted fractional derivative of the relative fluid velocity. In contrast to the exponential-type viscous relaxation models, the convolution operator in the Johnson–Koplik–Dashen dynamic permeability model cannot be replaced by memory variables satisfying first-order relaxation differential equations. A new method for calculating the shifted fractional derivative without storing and integrating the entire velocity histories is developed. Using the new method to calculate the fractional derivative, the governing equations for the two-dimensional porous medium are reduced to a system of first-order differential equations for velocities, stresses, pore pressure and the quadrature variables associated with the drag forces. Spatial derivatives involved in the first-order differential equations system are calculated by Fourier pseudospectral method, while the time derivative of the system is discretized by a predictor–corrector method. For the demonstration of our method, some numerical results are presented. [Copyright &y& Elsevier]

Peptidoglycan recognition proteins (PGRPs) belong to a member of pattern-recognition receptors (PRRs), which proposed as antibacterial protein. The present study investigated the antibacterial effect of BpPGRP5 in great blue-spotted mudskipper (Boleophthalmus pectinirostris). BpPGRP5 transcript was detected in all tested tissues with the highest expression level in spleen, and its expression was significantly upregulated in spleen, intestine, and kidney following Aeromonas veronii infection. rBpPGRP5 was found to interact with several polysaccharides and bacteria, including Gram-negative bacteria (Escherichia coli and A. veronii) and Gram-positive bacteria (Listeria monocytogenes and Staphylococcus aureus). rBpPGRP5 inhibited the proliferation of E. coli , S. aureus , L. monocytogenes , and A. veronii in a Zn2+-dependent manner. Furthermore, in vivo studies revealed that intraperitoneal injection of rBpPGRP5 improved the survival rate of A. veronii -infected B. pectinirostris , accompanied by decreased bacterial load in the blood, kidney, intestine, and spleen. Taken together, our results indicated that BpPGRP5 is an antimicrobial protein that protects B. pectinirostris against bacterial infection. • BpPGRP5 transcripts were altered in B. pectinirostris after A. veronii infection. • RBpPGRP5 bound to Lys-PGN, Dap-PGN, LTA, β-Glucan, Mannan, E. coli , A. veronii , L. monocytogenes , and S. aureus. • RBpPGRP5 administration improved the outcomes of A. veronii infected B. pectinirostris. [ABSTRACT FROM AUTHOR]

[Display omitted] Although certain members of the Ubiquitin-specific peptidases (USPs) have been recognized as promising therapeutic targets for various diseases, research progress regarding USP21 has been relatively sluggish in its early stages. USP21 is a crucial member of the USPs subfamily, involved in diverse cellular processes such as apoptosis, DNA repair, and signal transduction. Research findings from the past decade demonstrate that USP21 mediates the deubiquitination of multiple well-known target proteins associated with critical cellular processes relevant to both disease and homeostasis, particularly in various cancers. This review comprehensively summarizes the structure and biological functions of USP21 with an emphasis on its role in tumorigenesis, and elucidates the advances on the discovery of tens of small-molecule inhibitors targeting USP21, which suggests that targeting USP21 may represent a potential strategy for cancer therapy. [ABSTRACT FROM AUTHOR]

Micropterus salmoides rhabdovirus (MSRV) is one of the main pathogens of largemouth bass, leading to serious economic losses. The G protein, as the only envelope protein present on the surface of MSRV virion, contains immune-related antigenic determinants, thereby becoming the primary target for the design of MSRV vaccines. Here, we displayed the G protein on the surface of yeast cells (named EBY100/pYD1-G) and conducted a preliminary assessment of the protective efficacy of the recombinant yeast vaccine. Upon oral vaccination, a robust immune response was observed in systemic and mucosal tissue. Remarkably, following the MSRV challenge, the relative percent survival of EBY100/pYD1-G treated largemouth bass significantly increased to 66.7 %. In addition, oral administration inhibited viral replication and alleviated the pathological symptoms of MSRV-infected largemouth bass. These results suggest that EBY100/pYD1-G could be used as a potential oral vaccine against MSRV infection. • An oral vaccine was conducted by displaying MSRV G protein in the surface of Saccharomyces cerevisiae. • The oral vaccine induced high level of G protein specific antibody in largemouth bass. • Oral vaccination provided 66.7 % relative percent survival in MSRV-infected largemouth bass. • Oral administration suppressed the viral load and alleviated histological damage in largemouth bass tissues. [ABSTRACT FROM AUTHOR]

Abstract The glucocorticoid receptor (GR) is an important feedback regulator of the hypothalamic-pituitary-interrenal (HPI) axis. However, there are a limited number of studies focused on host-pathogen interactions in which an association between GR and immune response has been evaluated in monocytes/macrophages (MO/MФ) after being challenged with highly pathogenic bacteria. Here, we cloned the cDNA sequence of the glucocorticoid receptor (PaGR) gene from ayu fish. The PaGR transcript was expressed in all tissues, and changes in expression were observed in immune tissues and MO/MФ after live Vibrio anguillarum infection. Subsequently, PaGR was expressed and purified to prepare anti-PaGR antibodies. We analyzed the subcellular localization of PaGR. PaGR was expressed not only in the intracellular space but also in the plasma membrane. PaGR activation decreased the expression of pro-inflammatory cytokines and increased the expression of anti-inflammatory cytokines. However, PaGR activation suppressed the phagocytosis activity of V. anguillarum -infected ayu MO/MФ via a non-genomic pathway. Interestingly, PaGR activation could enhance MO/MФ bacterial killing capability and apoptosis. Therefore, PaGR may modulate the immune response in ayu MO/MФ by genomic and non-genomic pathways. Highlights • We characterized a GR gene from ayu, Plecoglossus altivelis. • GR transcripts were altered in ayu upon Vibrio anguillarum infection. • GR activation suppressed the phagocytosis of moncytes/macrophages via non-genomic pathway. • GR participated in the regulation of apoptosis in moncytes/macrophages. [ABSTRACT FROM AUTHOR]

• We characterized two POMC genes from ayu, Plecoglossus altivelis. • POMCs transcripts were altered in ayu after Vibrio anguillarum infection. • ACTH-B, but not ACTH-A, inhibited phagocytosis of monocytes/macrophages. • ACTH-A exerted anti-inflammatory effects on monocytes/macrophages through IL-10. Adrenocorticotropic hormone (ACTH), a bioactive peptide of the family of melanocortins, is generated from pro-opiomelanocortin (POMC). So far, the research on the specific functions of ACTH in the immune system of teleosts is limited. We determined two complementary DNA (cDNA) sequences of POMC in ayu (Plecoglossus altivelis), termed PaPOMC-A and PaPOMC-B. PaPOMCs transcripts occurred in all examined tissues, and their expression in immune tissues changed following experimental infection with Vibrio anguillarum. PaACTH-B, but not PaACTH-A, suppressed the phagocytosis of monocytes/macrophages (MO/MФ). Two isoforms of PaACTH increased the bactericidal capacity of MO/MФ. PaACTH-A increased anti-inflammatory cytokine expression, while PaACTH-B decreased pro-inflammatory cytokine expression in MO/MФ. Compared with PaACTH-B treatment, the PaACTH-A treatment improved survival rate and reduced the bacterial load in V. anguillarum- infected ayu through interleukin (IL)-10. Our results indicate that the two PaACTH isoforms exert different effects in the host defense against bacterial infection. [ABSTRACT FROM AUTHOR]