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231.
Zhai  Xiaofeng  Zhao  Wen  Li  Kemang  Zhang  Cheng  Wang  Congcong  Su  Shuo  Zhou  Jiyong  Lei  Jing  Xing  Gang  Sun  Haifeng  Shi  Zhiyu  Gu  Jinyan 《中国病毒学》2019,34(6):601-609
Since late 2011, outbreaks of pseudorabies virus(PRV) have occurred in southern China causing major economic losses to the pig industry. We previously reported that variant PRV forms and recombination in China could be the source of continued epidemics. Here, we analyzed samples from intensive pig farms in eastern China between 2017 and 2019, and sequenced the main glycoproteins(gB, gC, gD, and gE) to study the evolution characteristics of PRV. Based on the g C gene, we found that PRV variants belong to clade 2 and detected a founder effect during by the PRV epidemic. In addition,we detected inter-and intra-clade recombination; in particular, inter-clade recombination in the g B genes of strains FJ-ZXF and FJ-W2, which were recombinant with clade 1 strains. We also found specific amino-acid changes and positively selected sites, possibly associated with functional changes. This analysis of the emergence of PRV in China illustrates the need for continuous monitoring and the development of vaccines against specific variants of PRV.  相似文献   
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A novel, rapid and sensitive chemiluminescence (CL) method for the determination of oxytetracycline hydrochloride (OTCH) is described in this paper. The presented method was based on the fact that OTCH could immensely enhance the CL of the reaction of cerium sulfate and tris(2,2‐bipyridyl) ruthenium (II) in acidic medium. Under optimal experimental conditions, CL intensity was favorably linear for OTCH in the range 5.0 × 10?7 to 5.0 × 10?5 g/ml, with a detection limit of 1.5 × 10?7 g/ml (S/N = 3). The relative standard detection was 4.76% for 5.0 × 10?6 g/ml (n = 11). This method was successfully applied to the analysis of OTCH in milk and egg white samples. According to the results of the kinetic curves for OTCH in the Ru(bipy)32+–Ce(SO4)2 CL system, together with CL and ultraviolet (UV)–visible spectra, the possible mechanism of the CL reaction is discussed briefly.  相似文献   
234.
Flexible Na/K‐ion batteries (NIBs/KIBs) exhibit great potential applications and have drawn much attention due to the continuous development of flexible electronics. However, there are still many huge challenges, mainly the design and construction of flexible electrodes (cathode and anode) with outstanding electrochemical properties. In this work, a unique approach to prepare flexible electrode is proposed by utilizing the commercially available cotton cloth–derived carbon cloth (CC) as a flexible anode and the substrate of a cathode. The binder‐free, self‐supporting, and flexible cathodes (FCC@N/KPB) are prepared by growing Prussian blue microcubes on the flexible CC (FCC). Na/K‐ion full batteries (FCC//FCC@N/KPB) are assembled by using FCC and FCC@N/KPB as anode and cathode, respectively. Electrochemical performance, mechanical flexibility, and practicability of FCC//FCC@N/KPB Na/K‐ion full batteries are evaluated in both coin cells and flexible pouch cells, demonstrating their superior energy‐storage properties (excellent rate performance and cycling stability) and remarkable flexibility (they can work under different bending states). This work provides a new and profound strategy to design flexible electrodes, promoting the development of flexible NIBs/KIBs to be practical and sustainable.  相似文献   
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Yang  Xiangdong  Yang  Jing  Wang  Yisheng  He  Hongli  Niu  Lu  Guo  Dongquan  Xing  Guojie  Zhao  Qianqian  Zhong  Xiaofang  Sui  Li  Li  Qiyun  Dong  Yingshan 《Transgenic research》2019,28(1):103-114

Sclerotinia stem rot (SSR), caused by the oxalate-secreting necrotrophic fungal pathogen Sclerotinia sclerotiorum, is one of the devastating diseases that causes significant yield loss in soybean (Glycine max). Until now, effective control of the pathogen is greatly limited by a lack of strong resistance in available commercial soybean cultivars. In this study, transgenic soybean plants overexpressing an oxalic acid (OA)-degrading oxalate oxidase gene OXO from wheat were generated and evaluated for their resistance to S. sclerotiorum. Integration and expression of the transgene were confirmed by Southern and western blot analyses. As compared with non-transformed (NT) control plants, the transgenic lines with increased oxalate oxidase activity displayed significantly reduced lesion sizes, i.e., by 58.71–82.73% reduction of lesion length in a detached stem assay (T3 and T4 generations) and 76.67–82.0% reduction of lesion area in a detached leaf assay (T4 generation). The transgenic plants also showed increased tolerance to the externally applied OA (60 mM) relative to the NT controls. Consecutive resistance evaluation further confirmed an enhanced and stable resistance to S. sclerotiorum in the T3 and T4 transgenic lines. Similarly, decreased OA content and increased hydrogen peroxide (H2O2) levels were also observed in the transgenic leaves after S. sclerotiorum inoculation. Quantitative real-time polymerase chain reaction analysis revealed that the expression level of OXO reached a peak at 1 h and 4 h after inoculation with S. sclerotiorum. In parallel, a significant up-regulation of the hypersensitive response-related genes GmNPR1-1, GmNPR1-2, GmSGT1, and GmRAR occurred, eventually induced by increased release of H2O2 at the infection sites. Interestingly, other defense-related genes such as salicylic acid-dependent genes (GmPR1, GmPR2, GmPR3, GmPR5, GmPR12 and GmPAL), and ethylene/jasmonic acid-dependent genes (GmAOS, GmPPO) also exhibited higher expression levels in the transgenic plants than in the NT controls. Our results demonstrated that overexpression of OXO enhances SSR resistance by degrading OA secreted by S. sclerotiorum and increasing H2O2 levels, and eliciting defense responses mediated by multiple signaling pathways.

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l ‐Tyrosine is an essential aromatic amino acid required for the synthesis of proteins and a diverse array of plant natural products; however, little is known on how the levels of tyrosine are controlled in planta and linked to overall growth and development. Most plants synthesize tyrosine by TyrA arogenate dehydrogenases, which are strongly feedback‐inhibited by tyrosine and encoded by TyrA1 and TyrA2 genes in Arabidopsis thaliana. While TyrA enzymes have been extensively characterized at biochemical levels, their in planta functions remain uncertain. Here we found that TyrA1 suppression reduces seed yield due to impaired anther dehiscence, whereas TyrA2 knockout leads to slow growth with reticulate leaves. The tyra2 mutant phenotypes were exacerbated by TyrA1 suppression and rescued by the expression of TyrA2, TyrA1 or tyrosine feeding. Low‐light conditions synchronized the tyra2 and wild‐type growth, and ameliorated the tyra2 leaf reticulation. After shifting to normal light, tyra2 transiently decreased tyrosine and subsequently increased aspartate before the appearance of the leaf phenotypes. Overexpression of the deregulated TyrA enzymes led to hyper‐accumulation of tyrosine, which was also accompanied by elevated aspartate and reticulate leaves. These results revealed that TyrA1 and TyrA2 have distinct and overlapping functions in flower and leaf development, respectively, and that imbalance of tyrosine, caused by altered TyrA activity and regulation, impacts growth and development of Arabidopsis. The findings provide critical bases for improving the production of tyrosine and its derived natural products, and further elucidating the coordinated metabolic and physiological processes to maintain tyrosine levels in plants.  相似文献   
239.
We had previously identified that the co‐expression of transmembrane CXCL16 (TM‐CXCL16) and its receptor CXCR6 is an independent risk factor for poor survival in patients with diffuse large B‐cell lymphoma (DLBCL). However, the impact of the soluble form of CXCL16 (sCXCL16) on the pathogenesis of DLBCL remains unknown. In the present study, the synergistic effect of sCXCL16 and tumor necrosis factor α (TNF‐α) on apoptosis in DLBCL cell lines (OCI‐LY8 and OCI‐LY10) was investigated in vitro. sCXCL16 reinforced TNF‐α‐mediated inhibition of DLBCL cell proliferation, as determined by the cell counting kit‐8 assay. The results of annexin V staining showed that sCXCL16 enhanced TNF‐α‐induced apoptosis in OCI‐LY8 and OCI‐LY10 cells through a death receptor‐caspase signaling pathway. The results of gene microarray suggested a significant upregulation of differentially expressed genes in the TNF signaling pathway. sCXCL16 increased the concentration of extracellular TNF‐α by binding to CXCR6 to activate the nuclear factor‐κB (NF‐κB) signaling pathway. TNF‐α also induced the secretion of sCXCL16 by increasing the expression of ADAM10, which is known to cleave TM‐CXCL16 to yield sCXCL16. Moreover, bioinformatics analysis revealed that elevated TNF‐α and ADAM10 expression levels in tumor tissues predicted better survival in patients with DLBCL. Thus, our study suggests that sCXCL16 enhances TNF‐α‐induced apoptosis of DLBCL cells, which may involve a positive feedback loop consisting of TNF‐α, ADAM10, sCXCL16, and members of the NF‐κB pathway. sCXCL16 and TNF‐α may be used as prognostic markers in the clinic, and their combinational use is a promising approach in the context of DLBCL therapy.  相似文献   
240.
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