RESUMO
Porcine reproductive and respiratory syndrome (PRRS) is a globally prevalent contagious disease caused by the positive-strand RNA PRRS virus (PRRSV), resulting in substantial economic losses in the swine industry. Modifying the CD163 SRCR5 domain, either through deletion or substitution, can eff1ectively confer resistance to PRRSV infection in pigs. However, large fragment modifications in pigs inevitably raise concerns about potential adverse effects on growth performance. Reducing the impact of genetic modifications on normal physiological functions is a promising direction for developing PRRSV-resistant pigs. In the current study, we identified a specific functional amino acid in CD163 that influences PRRSV proliferation. Viral infection experiments conducted on Marc145 and PK-15 CD163 cells illustrated that the mE535G or corresponding pE529G mutations markedly inhibited highly pathogenic PRRSV (HP-PRRSV) proliferation by preventing viral binding and entry. Furthermore, individual viral challenge tests revealed that pigs with the E529G mutation had viral loads two orders of magnitude lower than wild-type (WT) pigs, confirming effective resistance to HP-PRRSV. Examination of the physiological indicators and scavenger function of CD163 verified no significant differences between the WT and E529G pigs. These findings suggest that E529G pigs can be used for breeding PRRSV-resistant pigs, providing novel insights into controlling future PRRSV outbreaks.
Assuntos
Antígenos CD , Antígenos de Diferenciação Mielomonocítica , Mutação Puntual , Síndrome Respiratória e Reprodutiva Suína , Vírus da Síndrome Respiratória e Reprodutiva Suína , Receptores de Superfície Celular , Animais , Suínos , Síndrome Respiratória e Reprodutiva Suína/genética , Síndrome Respiratória e Reprodutiva Suína/virologia , Vírus da Síndrome Respiratória e Reprodutiva Suína/fisiologia , Vírus da Síndrome Respiratória e Reprodutiva Suína/genética , Antígenos de Diferenciação Mielomonocítica/genética , Antígenos de Diferenciação Mielomonocítica/metabolismo , Antígenos CD/genética , Antígenos CD/metabolismo , Receptores de Superfície Celular/genética , Receptores de Superfície Celular/metabolismo , Animais Geneticamente Modificados/genética , Linhagem CelularRESUMO
Estuarine habitats are a critical zone of the Earth with strong land-sea interactions, that are strongly influenced by human activities. Microplastics (MPs) pollution in the Yellow River Delta (YRD) wetland, a typical young warm-temperate estuarine wetland, has not been comprehensively studied. The morphology, abundance, particle size, and polymer composition of MPs in the surface sediments of the YRD wetland were determined, and the pollution status and ecological risk in the study area were evaluated using the pollution load index (PLI) and potential pollution risk index (PRI). The results showed that the abundance of MPs in the YRD wetland was 20-520 n·kg-1, with a median value of 150 n·kg-1. The MPs were primarily fibers in shape and black in color, with particle size over 1 mm. The polymer components were primarily rayon, polyethylene, polyester, and polyethylene terephthalate. The PLI and PRI values of the MPs in the area were between 0.04-0.96 and 0.00-171.60, respectively, indicating that the pollution of MPs in the YRD wetland was at a slightly polluted level with low ecological risk.
RESUMO
Coastal wetlands are highly efficient in blue carbon sequestration. The impacts of climate warming on photosynthetic rates and light response characteristics of wetland plants would change the magnitude of carbon sequestration in coastal wetlands. We constructed warming observation stations in Phragmites australis (Phragmites) wetlands located in the Yellow River Delta in Dongying with dry climate, and in Yancheng by the Yellow Sea with wet climate. By using a Li-6800 photosynthesis system, we investigated the responses of simulated warming on photosynthetic characteristics of Phragmites in both wetlands, and compared the difference between months (June and August) in Dongying wetland. The results showed the photosynthetic rates of Phragmites were higher in June than in August. Warming increased net photosynthetic rate (Pn), transpiration rate (Tr), stomatal conductance (gs) and intercellular carbon dioxide concentration (Ci) in the two months, but the variability of Pn to warming was lower in August. The Pn and water use efficiency (WUE) of Phragmites in the Yancheng wetland were higher than Dongying wetland, and the maximum net photosynthetic rate (Pn max), light saturation point (LSP), apparent quantum efficiency (AQY), and dark respiration rate (Rd) of the former responded more positively to warming. The values of AQY, LSP and Pn max of Phragmites in the Yancheng wetlands were increased by 16.7%, 53.6% and 30.3%, respectively, in the warming plots. Our results suggested that warming could improve the utilization efficiency of weak light, the adaptability to strong light and photosynthetic potential of Phragmites under rainy and humid conditions. This study is of importance for accurately quantifying carbon sequestration of coastal wetlands at the regional and seasonal scales in the context of climate warming.
Assuntos
Poaceae , Áreas Alagadas , China , Transporte Biológico , FotossínteseRESUMO
The laccase and ultrasmall superparamagnetic iron oxide nanoparticles (USPIO) have been assembled inside the tubular mesoporous silica via co-adsorption technology to prepare host/guest-type immobilized laccase, which is applied to degrade methoxychlor (MXC) in aqueous and reverse micelle environments. The effects of various parameters on degradation of MXC were studied. Under the optimum conditions, the degradation rate could reach maximum value of 45.6 % and remain at 20.8 % after seven cycles. Moreover, the addition of small molecular compound 2, 2'-azinobis-(3-ethylbenzthiazoline-6-sulphonate) to the system could greatly improve the degradation efficiency. The MXC degradation process is a first-order reaction, and the activation energy of MXC degradation catalyzed by immobilized laccase (41.46 kJ mol(-1)) is relatively lower than that catalyzed by free laccase (44.91 kJ mol(-1)). Based on the degradation products measured by gas chromatograph-mass spectrometer (GC-MS) and nuclear magnetic resonance (NMR), the degradation mechanism of MXC has also been proposed.
Assuntos
Dextranos/química , Enzimas Imobilizadas/química , Inseticidas/química , Lacase/química , Nanopartículas de Magnetita/química , Metoxicloro/química , Adsorção , Benzotiazóis/química , Catálise , Micelas , Dióxido de Silício/química , Ácidos Sulfônicos/químicaRESUMO
The solvothermal reaction of zinc acetate dihydrate with a mixture of benzene-1,4-dicarboxylic acid (H(2)BDC) and benzene-1,3,5-tricarboxylic acid (H(3)BTC) in a solution containing N,N'-dimethylformamide (DMF), absolute ethanol, and chlorobenzene gave rise to a metal-organic polymer, Zn(3).BDC.2BTC.2NH(CH(3))(2).2NH(2)(CH(3))(2). The structure of this polymer possesses a unique three-dimensional framework with tri-zinc clusters, and BDC and BTC units colinking the clusters. Moreover, this metal-organic polymer exhibits strong photoluminescence at room temperature, and the main emission band is at about 430 nm (lambda(ex) = 325 nm). Crystal data for this compound (C(17)H(20)N(2)O(8)Zn(1.5)): monoclinic, space group P2(1)/n, cell dimensions a = 11.6171(3) A, b = 14.2456(4) A, c = 12.6426(3) A, beta = 107.030(2) degrees, V = 2000.51(9) A(3), and Z = 4.
RESUMO
The hydrothermal reaction of ZnUO2(OAc)4.7H2O with pyridine-2,3-dicarboxylic acid gives rise to a novel uranium-zinc-organic coordination polymer containing infinite U-O-Zn double sheets and organic ligands. Thermal and photoelectrochemical analyses indicate that the coordination polymeric compound not only has a high thermal stability but also exhibits interesting photoelectronic properties.