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Three-dimensional (3D) carbon-based materials have attracted growing attention in the field of electromagnetic wave absorption applications. However, their high conductivity results in high dielectric constant, leading to impedance mismatching, and this characteristic finally weakens their electromagnetic wave absorption performance. In this work, 3D carbon foam (3DCF) was successfully prepared by calcining the melamine foam as the carbon framework precursor under N 2 atmosphere. Subsequently, 1T-2H MoS 2 nanosheets were uniformly assembled on the surface of the 3DCF skeleton through a solvothermal process. The diameter of the 3DCF skeleton was about 1 μm and the thickness of the 1T-2H MoS 2 on the surface was about 150 nm. The 3D network brings in many advantages for microwave attenuation, including numerous conductive pathways, excellent impedance matching and multi-polarization processes. The composites exhibited a maximum reflection loss (RL max) of −45.88 dB at 10.2 GHz with the thickness of 2.2 mm, and the effective absorbing bandwidth (E AB) was as wide as 5.68 GHz, implying their superb microwave absorption behavior. This work is believed to offer a strategy for the design of efficient 3D electromagnetic wave absorbers with low density in the future. [ABSTRACT FROM AUTHOR]

Diamide insecticides have become the fourth most commonly used insecticide class in the world. Chlorantraniliprole (CAP) is a first-generation diamide insecticide with broad application potential. In this experiment, the eco-toxicity of CAP in soil at 0.1, 1.0, 5.0 and 10.0 mg/kg on earthworms ( Eisenia fetida ) was evaluated during a 42 d exposure. More specifically, the environmental fate and transport of CAP between soil and earthworms was monitored during the exposure period. The present results indicated that the CAP contents of 0.1, 1.0, 5.0 and 10.0 mg/kg treatments decreased to no more than 20% in the soil after 42 d of exposure. The accumulation of CAP in earthworms was 0.03, 0.58, 4.28 and 7.21 mg/kg earthworm (FW) at 0.1, 1.0, 5.0 and 10.0 mg/kg after 42 d of exposure. At 0.1 mg/kg and 1.0 mg/kg, CAP had no effect on earthworms during the exposure period. The weight of earthworms was significantly reduced at 5.0 and 10.0 mg/kg at 28 and 42 days after CAP application. After the 14th day, CAP induced excess production of reactive oxygen species (ROS) at 5.0 and 10.0 mg/kg, resulting in oxidative damage to biomacromolecules. We believe that CAP has a high risk potential for earthworms when used at 5.0 and 10.0 mg/kg. [ABSTRACT FROM AUTHOR]

Nanoparticles (NPs) derived from RNA interference (RNAi) are considered a potentially revolutionary technique in the field of plant protection in the future. However, the application of NPs in RNAi is hindered by the conflict between the high cost of RNA production and the large quantity of materials required for field application. This study aimed to evaluate the antiviral efficacy of commercially available nanomaterials, such as chitosan quaternary ammonium salt (CQAS), amine functionalized silica nano powder (ASNP), and carbon quantum dots (CQD), that carried double-stranded RNA (dsRNA) via various delivery methods, including infiltration, spraying, and root soaking. ASNP-dsRNA NPs are recommended for root soaking, which is considered the most effective method of antiviral compound application. The most effective antiviral compound tested was CQAS-dsRNA NPs delivered by root soaking. Using fluorescence, FITC-CQAS-dsCP-Cy3, and CQD-dsCP-Cy3 NPs demonstrated the uptake and transport pathways of dsRNA NPs in plants when applied to plants in different modes. The duration of protection with NPs applied in various modes was then compared, providing references for evaluating the retention period of various types of NPs. All three types of NPs effectively silenced genes in plants and afforded at least 14 days of protection against viral infection. Particularly, CQD-dsRNA NPs could protect systemic leaves for 21 days following spraying. [Display omitted] • The root soaking method was concluded to have higher efficiency of gene silencing. • The nanoparticles demonstrated to be transported upward by pooling in phloem when applied by the root soaking. • Efficient production of dsRNA targeting the full sequence of PVY virus using a prokaryotic expression system. [ABSTRACT FROM AUTHOR]

Neonicotinoid insecticides have become the most widely used pesticides in the world. Clothianidin is a novel neonicotinoid insecticide with a thiazolyl ring that exhibits excellent biological efficacy against a variety of pests. In the present study, the oxidative stress and genotoxicity of clothianidin on earthworms were evaluated. Moreover, the effective concentrations of clothianidin in artificial soil were monitored during the whole exposure period. The results showed that clothianidin was stable in artificial soil and that the residue concentrations were 0.094, 0.476, and 0.941 mg/kg after 28 d of exposure, which represented changes no more than 10% compared to the concentrations on the 0th day. Additionally, both the concentration of and exposure time to clothianidin had a substantial influence on biomarkers in earthworms. At 0.5 mg/kg and 1.0 mg/kg, the reactive oxygen species (ROS) levels were greatly enhanced, causing changes in antioxidant enzyme activities, damage to biological macromolecules and abnormal expression of functional genes. Additionally, the present results showed that superoxide dismutase (SOD), DNA damage and heat shock protein 70 (HSP70) may be good indicators for environmental risk assessment of clothianidin to earthworms. [ABSTRACT FROM AUTHOR]

[Display omitted] Absorbing materials can convert electromagnetic wave (EMW) energy into heat and other energy and dissipate it. Carbon materials can attenuate EMW by generating large conduction losses due to their high conductivity. The introduction of low dielectric materials can improve impedance matching caused by high conductivity. However, the density of materials compounded with carbon materials is too large, which affects the overall density of composite materials. Therefore, this problem is solved by matching melamine foam with ZIF-67. As an ultra-light material, the melamine foam-based carbon material can significantly reduce the density of composite materials, and its developed three-dimensional structure can cause multiple scattering of EMW. The large specific surface area and evenly distributed metal oxides obtained after annealing of ZIF-67 can provide ultra-low-density carbon materials and abundant interfacial polarization to further attenuate EMW. So far, the methods of self-growing materials on the surface of melamine foam have not been reported. We prepared a 500 nm Co 3 O 4 nanosheet/carbon foam (CF) composite material coated on the surface by a two-step method. The sample had a maximum reflection loss of −46.58 dB at 10.72 GHz, and an effective absorption bandwidth (EAB) of 5.4 GHz. This research provides a new idea for the growth of porous materials on the surface of melamine foam-based carbon materials. [ABSTRACT FROM AUTHOR]

Monodispersed Pd nanoparticles ranging from 2.8 to 8.0 nm with narrow size distribution are prepared and supported on TiO 2 for photo-thermal catalytic RWGS reaction. The catalytic activity presents volcano-type dependence over Pd sizes with 6.3 Pd/TiO 2 exhibiting the highest activity. [Display omitted] • A library of monodispersed Pd nanoparticles with successively increased sizes from 2.8, 3.4, 4.7, 5.3, 6.3 and 8.1 nm were prepared. • The photo-thermal catalytic activity towards RWGS reaction presents volcano-type dependence over Pd sizes with 6.3 Pd/TiO 2 giving the highest activity. • The size-modulated activity can be attributed to the tunable surface electronic properties including metal-support interaction and quantum size effect. Size of metal nanoparticles significantly influences their catalytic behaviors. However, it is still challenging to obtain monodispersed metal nanoparticles with successively tuned sizes to unveil their size-dependent catalytic performances, especially for photo-thermal catalytic reverse water–gas shift (RWGS) reaction. Herein, a library of Pd nanoparticles of 2.8, 3.4, 4.7, 5.3, 6.3 and 8.1 nm were synthesized and supported on TiO 2 for photo-thermal catalytic RWGS reaction. The catalytic activity presented volcano-like dependence on sizes of Pd nanoparticles with 6.3 Pd/TiO 2 exhibiting the highest catalytic efficiency. Based on the results of X-ray photoelectron spectroscopic analysis, photo-to-thermal conversion efficiency evaluation and density functional theory (DFT) calculations following the formate (*HCOO) pathway revealed by in situ diffuse reflectance infrared Fourier transform spectroscopy (in situ DRIFTS) measurements, the volcano-type tendency in catalytic activity could be attributed to the superposition of size-governed surface electronic properties over Pd nanoparticles. [ABSTRACT FROM AUTHOR]

[Display omitted] One-dimensional carbon-based materials have emerged as promising electromagnetic wave absorption agents due to their outstanding conductivity, high stability, low weight, and easy availability. Properly optimizing their electromagnetic parameters is expected to further enhance the electromagnetic wave attenuation capacity. In this work, efficient Cu 9 S 5 /C nanocomposite fibers are prepared by a combined approach of electrospinning and subsequent carbonization-sulfurization processes. The Cu 9 S 5 nanoparticles with size of ca. 100–200 nm were homogeneously embedded in fibrous carbon matrix with diameter of 300 nm. For electromagnetic wave absorption, the optimized composited nanofibers (Cu 9 S 5 /C-3) exhibited an extremely superb reflection loss of −65.4 dB (9.5 GHz, 2.7 mm) at a lower mass fraction (20 wt%). And the effective absorption bandwidth could be up to 4.1 GHz (8.0–12.1 GHz) with a matching thickness of 2.9 mm, covering the whole X-band. Electromagnetic wave attenuation mechanism investigation revealed that the performance enhancement originated from the synergy of various loss pathways, including interfacial polarization, dipole polarization, and conductive loss. The unique hierarchical structure from particle embedding, one-dimensional fiber, to three-dimensional network further amplified the performance advantages of each component. This work is anticipated to provide a feasible strategy to synthesize sulfide/carbon binary composite fibers for efficient electromagnetic wave absorption. [ABSTRACT FROM AUTHOR]

[Display omitted] Regulating electromagnetic parameters and thus improving impedance matching characteristics by multi-component design is regarded as a prospective approach to obtain highly efficient electromagnetic wave absorption materials. Whereas, it is still challenging to fabricate microwave absorbers with strong absorption capacity and durability in harsh conditions. Based on the above considerations, three-dimensional porous multi-functional manganese oxide/nickel/carbon microspheres had been designed and prepared through a combined approach of facile solvothermal reactions and subsequent carbonization processes. The textural characteristic examinations demonstrated that, numerous manganese oxide and Ni nanoparticles of 15–20 nm in diameter were well dispersed in the carbon-based microspheres of approximately 0.8–1 μm in size. Microwave absorption property evaluation indicated that the minimum reflection loss reached up to −53.6 dB at 9.5 GHz, and effective absorption bandwidth of 3.7 GHz was achieved at matching thickness of merely 2.0 mm. The electromagnetic wave attenuation mechanisms analysis displayed that excellent impedance matching and various dissipation pathways, including magnetic loss, interfacial and dipole polarization relaxation synergistically contributed to the high microwave absorption performances of the porous composites. Radar cross-sectional simulation and photothermal measurements verified that the materials were supposed to have promising foregrounds in complicated circumstances. [ABSTRACT FROM AUTHOR]

This work reported a NIR-II window triple-mode synergistic antibacterial nanoplatform cCuS@Van NPs, providing a reference for the future development of multi-mode antibacterial therapeutic nanoplatforms. [Display omitted] The widespread use of antibiotics leads to the increasing drug resistance of bacteria and poses a threat to human health. Therefore, there is an urgent need to develop new antibacterial strategies. Herein, based on the good photothermal properties of Copper sulfide (CuS) nanoparticles under near infrared (NIR) laser, we developed a NIR-Ⅱ window triple-mode synergetic antibacterial cCuS (cationic CuS) @Vancomycin (Van) nanoplatform. In the proposed nanoplatform, the positive charge on the surface makes cCuS@Van nanoplatform show better bacterial uptake and membrane damage; vancomycin induces chemical sterilization and provides a targeting effect to the nanoplatform; combined with the strong photothermal effect and deep tissue penetration at the excitation of 1064 nm laser, cCuS@Van nanoplatform can effectively kill bacterial. The photothermal conversion efficiency of the nanoplatform can reach 49.12 % and in vitro experiments show a sterilizing rate of more than 99.5 % to staphylococcus aureus (S. aureus) at the concentration of 3.0 μM, which also demonstrated the synergistic effect of cCuS@Van nanoplatform. In addition, low cytotoxicity to human cells conforms the good biocompatibility of the as-prepared cCuS@Van nanoplatform, which endows it a good application prospect in the field of antibacterial, such as wound healing and implant sterilization. [ABSTRACT FROM AUTHOR]

[Display omitted] Globally, drug-resistant bacteria are a potential threat to human society owing to the overuse of antibiotics and thus, non-antibiotic bactericides are urgently needed. Herein, an innovative antibacterial nanoplatform based on quaternized chitosan (QCS)/ silver (Ag)/ cobalt phosphide (CoP) nanocomposites is envisaged for achieving near-infrared (NIR) laser-inducible rapid sterilisation. In the core-shell hybrids, Ag nanoparticles (NPs) with a size of ∼ 25 nm were uniformly deposited on CoP nanoneedles, upon which a layer of QCS (approximately 10 wt%), is coated. Numerical calculations revealed that under NIR irradiation, high-energy hot electrons arising from the surface plasmon resonance effect of Ag migrate into the interface between Ag and CoP, and amplify the photothermal effect of CoP. Meanwhile, photo-excited electrons from CoP are transported onto Ag NPs because the Schottky heterostructure facilitates the production of reactive oxygen species. Ag loading simultaneously enhances the photocatalytic and photothermal effects of CoP, achieving rapid antibacterial activity synergistically. The QCS coating improves the dispersibility of power in an aqueous system and provides contact between the antiseptics and bacteria. The ternary QCS/Ag/CoP nanocomposites achieved greater than 99.6% inactivation against S. aureus and E. coli within 10 min. In addition, the nanocomposites were confirmed to be noncytotoxic to mammals. Consequently, the QCS/Ag/CoP nanoplatforms possess great potential for rapid and effective antibacterial applications. [ABSTRACT FROM AUTHOR]

The optimal impedance matching and strong dissipation ability could be obtained by tuning the content of NiS and ZnS in the ZnS/NiS/C hollow spheres. The synergistic effects between ZnS and NiS on absorbing performances were thoroughly investigated. [Display omitted] Utilizing the synergistic effect of multiple components in heterostructured composites has been regarded as a promising strategy for achieving high-performance electromagnetic wave absorption. Nonetheless, rationally collocate the components of absorbers in order to legitimately achieve synergy remains an intractable problem. By adjusting the NiS and ZnS composition ratios in the ZnS/NiS/C composites, the optimal impedance matching and dissipation capability can be obtained. The formation of a ZnS/NiS heterostructure is found to significantly enhance polarization relaxation, and the relative ratios of ZnS and NiS have a significant effect on the electromagnetic properties. The optimal performance was obtained on Z1N2, with a minimum reflection loss of –51.45 dB at 4.72 GHz and –56.69 dB at 11.12 GHz, respectively, and an effective absorption bandwidth of up to 3.68 GHz at 1.16 mm. The potential of heterogeneous bimetal sulfides as high-performance absorbers is demonstrated in this study. [ABSTRACT FROM AUTHOR]

Abstract: Monodispersed Ni flower-like architectures with size of 1–2μm were synthesized through a facile solvent-thermal process in 1,2-propanediol solution in the presence of polyethylene glycol (PEG) and sodium alkali for electromagnetic absorption application. The Ni architectures are composed of nanoflakes, which assemble to form three dimensional flower-like structure, and the thickness of nanoflakes is about 10–40nm. A possible formation mechanism for Ni flower-like architectures was proposed and it was confirmed by the control experiments. The Ni architectures exhibited a saturation magnetization (M s) of 47.7emu/g and a large coercivity (H cj) of 332.3Oe. The epoxy resin composites with 20vol% Ni sample provided good electromagnetic wave absorption performance (reflection loss <−20dB) in the range of 2.8–6.3GHz over absorber thickness of 2.6–5.0mm. [Copyright &y& Elsevier]

Tobacco mosaic virus (TMV) is widespread in China and causes considerable economic losses to tobacco production. The molecular epidemiology of this virus is, however, poorly understood. In this study, we sequenced the genomes of 51 TMV isolates from five tobacco-producing regions in China and investigated the dispersal patterns of this virus. Our phylogenetic analysis showed that TMV might have been introduced to China in the early 1900s, probably first to southwest China. However, TMV then moved to the north of the country, where it expanded. The north became the main seeding region for the subsequent movements of the virus within China. The north-to-south movement of TMV coincides with a shift of major tobacco-producing areas from north to south in this century, suggesting a link between human activities and the dispersal of TMV in China. • TMV was introduced into the Southwest producing region of China before its spread through the country. • Gene flow has occurred between TMV populations, generally along a north-to-south axis in China. • Demographic expansions of TMV in China are potentially linked to tobacco production. [ABSTRACT FROM AUTHOR]

Staphylococcus aureus is a common Gram-positive pathogen that causes bovine mastitis, a persistent infection of the bovine mammary gland. Bovine mammary epithelial cells (BMEC) are important parenchymal cells of the bovine mammary gland. To better understand the importance of BMEC and the roles of the TLR-NF-κBand TLR-AP-1 signaling pathways in the regulation of S. aureus -associated mastitis and mammary fibrosis, BMEC cultured in vitro were stimulated with different concentrations of heat-inactivated S. aureus to analyze the gene and protein expression and production of toll-like receptor 2 (TLR2), toll-like receptor 4 (TLR4), transforming growth factor beta 1 (TGF-β1), basic fibroblast growth factor (bFGF) as well as the protein expression of nuclear factor-kappa B (NF-κB) and activation protein-1 (AP-1) by means of quantitative polymerase chain reaction (qPCR) and western blotting, respectively. Specific NF-κB and AP-1 inhibitors were also used to investigate their effects on the regulation of TGF-β 1 and bFGF expression. The results indicated that, in addition to increasing mRNA expression and secretion of TLR2 and TLR4, S. aureus could also upregulate TGF-β 1 and bFGF mRNA expression and secretion through the activation of NF-κB and AP-1. The increase in TGF-β 1 and bFGF expression was shown to be inhibited by AP-1- and NF-κB-specific inhibitors. Taken together, S. aureus induces TGF-β1 and bFGF expression through the activation of AP-1 and NF-κB in BMECs. This information offers new potential targets for the treatment of bovine mammary fibrosis. [ABSTRACT FROM AUTHOR]

Sulphated lentinan (sLTN) is known to act as a resistance inducer by causing programmed cell death (PCD) in tobacco suspension cells. However, the underlying mechanism of this effect is largely unknown. Using tobacco BY-2 cell model, morphological and biochemical studies revealed that mitochondrial reactive oxygen species (ROS) production and mitochondrial dysfunction contribute to sLNT induced PCD. Cell viability, and HO/PI fluorescence imaging and TUNEL assays confirmed a typical cell death process caused by sLNT. Acetylsalicylic acid (an ROS scavenger), diphenylene iodonium (an inhibitor of NADPH oxidases) and protonophore carbonyl cyanide p -trifluoromethoxyphenyl hydrazone (a protonophore and an uncoupler of mitochondrial oxidative phosphorylation) inhibited sLNT-induced H 2 O 2 generation and cell death, suggesting that ROS generation linked, at least partly, to a mitochondrial dysfunction and caspase-like activation. This conclusion was further confirmed by double-stained cells with the mitochondria-specific marker MitoTracker RedCMXRos and the ROS probe H 2 DCFDA. Moreover, the sLNT-induced PCD of BY-2 cells required cellular metabolism as up-regulation of the AOX family gene transcripts and induction of the SA biosynthesis, the TCA cycle, and miETC related genes were observed. It is concluded that mitochondria play an essential role in the signaling pathway of sLNT-induced ROS generation, which possibly provided new insight into the sLNT-mediated antiviral response, including PCD. [ABSTRACT FROM AUTHOR]

Staphylococcus aureus is a common Gram-positive pathogen that causes bovine mastitis, a persistent infection of the bovine mammary gland. To better understand the importance of bovine mammary fibroblasts (BMFBs) and the roles of the TLR–NF-κB and TLR–AP-1 signaling pathways in the regulation of S. aureus -associated mastitis and mammary fibosis, BMFBs cultured in vitro were stimulated with different concentrations of heat-inactivated S. aureus to analyze the gene and protein expression of toll-like receptor 2 (TLR2), toll-like receptor 4 (TLR4), transforming growth factor beta 1 (TGF-β 1 ), basic fibroblast growth factor (bFGF) as well as the protein expression of nuclear factor-kappa B (NF-κB) and activation protein-1 (AP-1) by means of quantitative polymerase chain reaction (qPCR) and western blotting, respectively. Specific NF-κB and AP-1 inhibitors were also used to investigate their effects on the regulation of TGF-β 1 and bFGF expression. The results indicated that, in addition to increasing mRNA and protein expression of TLR2 and TLR4, S. aureus could also upregulate TGF-β 1 and bFGF mRNA expression and secretion through the activation of NF-κB and AP-1. The increase in TGF-β 1 and bFGF expression was shown to be inhibited by AP-1- and NF-κB-specific inhibitors. Taken together, S. aureus induces TGF-β 1 and bFGF expression through the activation of AP-1 and NF-κB in BMFBs. This information offers new potential targets for the treatment of bovine mammary fibrosis. [ABSTRACT FROM AUTHOR]

[Display omitted] • Bacillus siamensis LZ88 showed significant antifungal activity against A. alternata. • Non-volatile and volatile organic compounds against A. alternata were identified. • LZ88 is a promising alternative to agrochemicals for biocontrol of A. alternata. Our previous study identified that Bacillus siamensis strain LZ88 has significant antagonistic activity against a variety of pathogenic fungi, especially against Alternaria alternata , which causes tobacco brown spot. In the present study, the non-volatile compounds and volatile organic compounds (VOCs) produced by LZ88 were identified and tested for their antifungal activities. The non-volatile compounds had significant inhibitory effects on both mycelial growth and spore germination of A. alternata , with IC 50 values of 24.25 μg/mL and 29.04 μg/mL, respectively. HPLC-DAD-ESI-MS/MS analysis revealed that the non-volatile compounds which showed antifungal activities were iturins and macrolactin. HS-SPME-GC–MS identified ten VOCs from strain LZ88, including 8 ketones and 2 acids. Among the VOCs tested, 2-methylbutanoic acid and 3-methylbutanoic acid exhibited significant antifungal activity against A. alternata. Both 2-methylbutanoic acid and 3-methylbutanoic acid could inhibit mycelium growth of A. alternata with IC 50 values of 83.10 mg/mL and 104.19 mg/mL, whereas inhibited spore germination with IC 50 values of 139.63 mg/mL and 88.07 mg/mL, respectively. Furthermore, when exposed to non-volatile compounds or VOCs, the hyphae and spores of A. alternata were deformed and collapsed, and consequent hyphae without any attached conidia appeared ruptured, shrunken, and twisted. Additionally, the genetic mechanisms were analyzed by whole genome sequencing, and the gene clusters responsible for antibacterial metabolites were mined. These results indicate that strain LZ88 possessed a remarkable potential as alternative agrochemicals toward A. alternata. [ABSTRACT FROM AUTHOR]

The inhibitory effects of sulfated lentinan with different degrees of sulfation against tobacco mosaic virus (TMV) and the underlying mechanism were investigated. The results indicated that plants treated with increasing concentrations of sulfated lentinan, with increasing numbers of treatments and with increasing time after treatment had a decrease in the number of necrotic lesions, indicating a long-term protection against TMV that mimics vaccination. In addition, the levels of TMV-capsid protein (CP) transcripts decreased in distant leaves, indicating that sulfated lentinan induces systemic protection against TMV. The activities of the defense enzymes phenylalanine ammonia lyase (PAL) and lipoxygenase (LOX) and the amounts of several phenylpropanoid compounds (PPCs) were measured in control and treated plants without infection. A progressive increase in PAL activity was observed with increasing time after treatment, together with the accumulation of free and conjugated PPCs. In contrast, LOX activity remained unchanged. Interestingly, the increase in PAL activity showed a linear correlation with the decrease in necrotic lesions and the decrease in TMV-CP transcript level. Thus, sulfated lentinan induced systemic and long-term protection against TMV in tobacco plants that is determined, at least in part, by a sustained activation of PAL and the accumulation of PPCs with potential antiviral activity. [ABSTRACT FROM AUTHOR]

Prostaglandin E2 (PGE 2) enhances Staphylococcus aureus infection but its mechanism is not well understood. Here, we examined the effect of PGE 2 on Staphylococcal Protein A (SPA) expression in bovine endometrium and determined the role of select PGE 2 receptors (i.e., EP2 and EP4) in adhesion and internalization of S. aureus. S. aureus isolate SA113 was used for in vitro infection of bovine endometrial tissues and epithelial cells, with treatment conditions consisting of untreated control, SA113 treatment, SA113 + PGE 2 , SA113 + PGE 2 + EP2 receptor antagonist (AH-6809), and SA113 + PGE 2 + EP4 receptor antagonist (AH-23848). Immunofluorescence assay revealed that PGE 2 could promote SPA expression in S. aureus -infected bovine endometrial tissues. PGE 2 also enhanced the adhesion and internalization of S. aureus in bovine endometrial cells. The addition of EP4 antagonist, but not the EP2 antagonist, abrogated the ability of PGE 2 to promote S. aureus SPA expression, adhesion, and internalization in endometrial cells. Our findings suggest that S. aureus infection in the endometrium is enhanced by PGE 2 through the EP4 receptor. This result is essential for the development of new approach to treating S. aureus infection, such as the application of EP4 antagonist as an adjunct drug treatment. • PGE 2 increased SPA expression in S. aureus -infection BECs. • PGE 2 strengthen adhesion and invasion of S. aureus into BECs via EP4 receptor not EP2 receptor. • EP4 receptor may be as a research target to treat bovine endometritis caused by S. aureus. [ABSTRACT FROM AUTHOR]

• Bacillus siamensis could suppress the mycelial growth and sporulation of Alternaria alternata. • Bacillus siamensis increased defense-related enzyme activities in tobacco plant. • It could be potential PGPR used to control tobacco brown spot disease. Tobacco brown spot disease, caused by Alternaria alternata , is responsible for causing significant losses in tobacco production in China. The use of biocontrol microorganisms to prevent and control this disease represent an important, environment-friendly, management strategy. In the present study, 17 bacterial strains with antimicrobial activity were isolated from 40 rhizosphere soil samples and evaluated for antifungal activity to identify an effective biocontrol agent for the control of tobacco brown spot disease in tobacco. Among the isolated strains, Bacillus siamensis, strain LZ88, exhibited the strongest antifungal activity with an inhibition rate of 81.96%. We confirmed that strain LZ88 controlled both mycelial growth and spore production in A. alternata by secreting protein-like antifungal metabolites and through the release of volatile organic compounds. Strain LZ88 also had the ability to induce plant basal immunity as evidenced by increased expression of the defense-related enzymes, peroxidase (POD) and polyphenol oxidase (PPO), in tobacco leaves. Results of greenhouse experiments indicated that LZ88 could effectively reduce the occurrence and degree of severity of tobacco brown spot disease. To the best of our knowledge, this is the first report regarding the use of B. siamensis to control brown spot disease in tobacco. [ABSTRACT FROM AUTHOR]

To investigate the TLR–NF–κB/AP-1 pathways in S. aureus infection-induced mammary gland fibrosis, mice were infected with S. aureus isolated from the mammary glands of cows with mastitis. Lactating mice were divided into three groups: control group (CON); PBS control group (PBS) and the S. aureus -treated group (S. aureus). Pathological observations revealed that neutrophil infiltration into mammary gland tissue was obviously induced by S. aureus at the early stage of infection (1–7 d). With persistent S. aureus infection, mammary gland fibrosis developed and was characterized by infiltration and proliferation of macrophage, lymphocyte and fibroblast and ECM hyperplasia (7–21 d). Immunohistochemistry staining showed upregulation of fibrosis associated cytokines viz bFGF and PDGF-BB. Real-time qPCR and Western blot analysis revealed that transcription and translation of TLR2, TLR4, bFGF, PDGF-BB, α-SMA and COL Ⅰ α1 was significantly upregulated by S. aureus. NF-κB p65 and AP-I c-jun were translocated into the nucleus after S. aureus infection. There was no remarkable difference between the CON and PBS groups. The datas indicate that mammary gland fibrosis in mice is induced by S. aureus , which promotes cytokine release and the expression of ECM though activating the TLR/NF-κB p65 and TLR/AP-1 c-jun signaling pathways. • S. aureus induces fibrogenesis in the murine mammary gland. • S. aureus increases mammary fibroblast activation in mice. • S. aureus increases bFGF and PDGF-BB expression in mammary gland tissue. • The TLR/NF-κB and TLR/AP-1 signaling pathways increase α-SMA and COL I α1 expression in fibrotic mammary gland tissue. [ABSTRACT FROM AUTHOR]