Summary
Porcine reproductive and respiratory syndrome virus (PRRSV) is a major economically significant pathogen that has adversely affected China's swine industry. Currently, a novel type 2 PRRSV, ...called the NADC30‐like strain, is epidemic in numerous provinces of China, and commercial vaccines provide limited protection for infected animals. The extensive recombination phenomenon among NADC30‐like PRRSVs is identified as a unique molecular characteristic of the virus. However, our understanding of how recombination influences NADC30‐like PRRSVs is largely inadequate. In this study, we analysed the genetic characteristics of a recombinant NADC30‐like PRRSV (SC‐d) and examined its pathogenicity compared with a non‐recombinant NADC30‐like PRRSV (SD‐A19) and a highly pathogenic PRRSV (HuN4). SC‐d has three discontinuous deletions in nsp2, consistent with NADC30 isolated from the United States in 2008. Furthermore, we identified four recombination breakpoints in the SC‐d genome, which separated the SC‐d genome into four regions (regions A, B, C and D). Regions A and C are closely related to the JXA1‐like strain, one of the earliest Chinese HP‐PRRSV strains, and regions B and D are closely related to the NADC30 strain. Moreover, SC‐d inoculated piglets exhibited a persistent fever, moderate weight loss, mild thymus atrophy and obvious microscopic lung lesions. In summary, the recombinant NADC30‐like PRRSV SC‐d strain displayed a higher pathogenicity than the non‐recombinant NADC30‐like PRRSV SD‐A19 strain; however, the pathogenicity of the NADC30‐like PRRSV SC‐d was lower compared with the HP‐PRRSV HuN4 strain in piglets. Our findings demonstrate that recombination is responsible for the enormous genetic diversity and pathogenicity variance of the NADC30‐like PRRSV in China. This study provides a theoretical basis for developing a more reasonable PRRSV control and prevention strategy.
This study is the first in a series of papers that aim to develop high-resolution emission databases for different anthropogenic sources in China. Here we focus on on-road transportation. Because of ...the increasing impact of on-road transportation on regional air quality, developing an accurate and high-resolution vehicle emission inventory is important for both the research community and air quality management. This work proposes a new inventory methodology to improve the spatial and temporal accuracy and resolution of vehicle emissions in China. We calculate, for the first time, the monthly vehicle emissions for 2008 in 2364 counties (an administrative unit one level lower than city) by developing a set of approaches to estimate vehicle stock and monthly emission factors at county-level, and technology distribution at provincial level. We then introduce allocation weights for the vehicle kilometers traveled to assign the county-level emissions onto 0.05° × 0.05° grids based on the China Digital Road-network Map (CDRM). The new methodology overcomes the common shortcomings of previous inventory methods, including neglecting the geographical differences between key parameters and using surrogates that are weakly related to vehicle activities to allocate vehicle emissions. The new method has great advantages over previous methods in depicting the spatial distribution characteristics of vehicle activities and emissions. This work provides a better understanding of the spatial representation of vehicle emissions in China and can benefit both air quality modeling and management with improved spatial accuracy.
The midline pattern of sternal ossification characteristic of the Cretaceous enantiornithine birds is unique among the Ornithodira, the group containing birds, nonavian dinosaurs and pterosaurs. This ...has been suggested to indicate that Enantiornithes is not the sister group of Ornithuromorpha, the clade that includes living birds and their close relatives, which would imply rampant convergence in many nonsternal features between enantiornithines and ornithuromorphs. However, detailed comparisons reveal greater similarity between neornithine (i.e. crown group bird) and enantiornithine modes of sternal ossification than previously recognized. Furthermore, a new subadult enantiornithine specimen demonstrates that sternal ossification followed a more typically ornithodiran pattern in basal members of the clade. This new specimen, referable to the Pengornithidae, indicates that the unique ossification pattern observed in other juvenile enantiornithines is derived within Enantiornithes. A similar but clearly distinct pattern appears to have evolved in parallel in the ornithuromorph lineage. The atypical mode of sternal ossification in some derived enantiornithines should be regarded as an autapomorphic condition rather than an indication that enantiornithines are not close relatives of ornithuromorphs. Based on what is known about molecular mechanisms for morphogenesis and the possible selective advantages, the parallel shifts to midline ossification that took place in derived enantiornithines and living neognathous birds appear to have been related to the development of a large ventral keel, which is only present in ornithuromorphs and enantiornithines. Midline ossification can serve to medially reinforce the sternum at a relatively early ontogenetic stage, which would have been especially beneficial during the protracted development of the superprecocial Cretaceous enantiornithines.
Background
Glycolysis is a critical pathway in cellular glucose metabolism that provides energy and participates in immune responses. However, whether glycolysis is involved in NOD‐like receptor ...family protein 3 (NLRP3) inflammasome activation and phagocytosis of macrophages in response to Treponema pallidum infection remains unclear.
Objectives
To investigate the role of glycolysis in activating the NLRP3 inflammasome for regulating phagocytosis in macrophages in response to T. pallidum protein Tp47 and its associated mechanisms.
Methods
Interactions between activation of the NLRP3 inflammasome and phagocytosis and the role of glycolysis in Tp47‐treated macrophages were investigated through experiments on peritoneal macrophages and human monocytic cell line‐derived macrophages.
Results
Activation of phagocytosis and NLRP3 inflammasome were observed in Tp47‐treated macrophages. Treatment with NLRP3 inhibitor MCC950 or si‐NLRP3 attenuated Tp47‐induced phagocytosis. Glycolysis and glycolytic capacity were enhanced by Tp47 stimulation in macrophages, and a change in the levels of glycolytic metabolites (phosphoenolpyruvate, citrate and lactate) was induced by Tp47 in macrophages. Inhibition of glycolysis with 2‐deoxy‐D‐glucose, a glycolysis inhibitor, decreased the activation of NLRP3. Expression of M2 isoform of pyruvate kinase (PKM2), an enzyme catalysing a rate‐limiting reaction in the glycolytic pathway, was upregulated in Tp47‐stimulated macrophages. Inhibition of PKM2 with shikonin or si‐PKM2 decreased glycolysis and NLRP3 activation.
Conclusion
Tp47 promotes phagocytosis in macrophages by activating the NLRP3 inflammasome, which is induced by the enhancement of PKM2‐dependent glycolysis.
The non‐classical function of acetylcholine (ACh) has been reported in neuroinflammation that represents the modulating factor in immune responses via activation of α7 nicotinic acetylcholine ...receptor (α7 nAChR), i.e., a cholinergic anti‐inflammatory pathway (CAP). Acetylcholinesterase (AChE), an enzyme for ACh hydrolysis, has been proposed to have a non‐classical function in immune cells. However, the involvement of AChE in neuroinflammation is unclear. Here, cultured BV2 cell, a microglial cell line, and primary microglia from rats were treated with lipopolysaccharide (LPS) to induce inflammation and to explore the regulation of AChE during this process. The expression profiles of AChE, α7 nAChR, and choline acetyltransferase (ChAT) were revealed in BV2 cells. The expression of AChE (G4 form) was induced significantly in LPS‐treated BV2 cells: the induction was triggered by NF‐κB and cAMP signaling. Moreover, ACh or α7 nAChR agonist suppressed the LPS‐induced production of pro‐inflammatory cytokines, as well as the phagocytosis of microglia, by activating α7 nAChR and followed by the regulation of NF‐κB and CREB signaling. The ACh‐induced suppression of inflammation was abolished in AChE overexpressed cells, but did not show a significant change in AChE mutant (enzymatic activity knockout) transfected cells. These results indicate that the neuroinflammation‐regulated function of AChE may be mediated by controlling the ACh level in the brain system.
ABSTRACT
This experiment was conducted to evaluate the effects of dietary supplementation with Clostridium butyricum on laying performance, egg quality, serum parameters, and cecal microflora of ...laying hens in the late phase of production. Jinghong-1 strain laying hens (n = 960; 48 wk of age) were randomly allocated to 5 treatment groups with 6 replicates of 32 hens. Hens were fed with basal diet (control) and basal diet supplemented with 2.5 × 104 (CB1), 5 × 104 (CB2), 1 × 105 (CB3), and 2 × 105 (CB4) cfu/g C. butyricum for 10 wk. The results showed that egg production, egg mass, and eggshell strength increased quadratically as supplemental C. butyricum increased, and these responses were maximized in the CB2 group (P < 0.05). Compared with the control group, the addition of C. butyricum resulted in quadratic effects on serum total protein, uric acid, calcium, complement component C3 and catalase concentrations, and these responses were maximized or minimized in the CB2 group (P < 0.05). Linear and quadratic increases were observed in serum IgM, total superoxide dismutase, and glutathione peroxidase concentrations, and these responses were maximized in CB2 or CB3 group (P < 0.05). The addition of C. butyricum in the CB2 group resulted in linearly increasing levels of serum IgG concentration as compared with the control group (P < 0.05). Spleen index increased (P < 0.05) in the CB2 group. Hens fed with C. butyricum reduced (P > 0.05) the population of E. coli, while Bifidobacterium counts increased quadratically and maximized in the CB2 group (P < 0.05). In conclusion, the results indicated that dietary supplementation with C. butyricum (5 × 104 or 1 × 105 cfu/g) could improve laying performance and egg quality by promoting immune function, enhancing antioxidative capacity, and benefiting the cecal microflora of laying hens in the late phase of production.
ABSTRACT
This study was to determine the effects of dietary Zn-methionine (Zn-Met) supplementation on the laying performance, egg quality, antioxidant capacity, and serum parameters of laying hens. ...Jingh ong-1 strain laying hens (n = 720, 49 wk of age) were randomly assigned to 6 treatments with 6 replications of 20 birds. The control was fed a basal diet supplemented with 80 mg of Zn/kg as Zn sulphate of diet and the 5 groups were fed a basal diet supplemented with 20, 40, 60, 80, and 100 mg of Zn/kg as Zn-Met of diet for 10 wk, respectively. At the terminal experiment, there were significant differences between control and 80 mg/kg Zn-Met group in feed intake (P < 0.05) and feed conversion ratio (FCR) (P < 0.01). Egg weight (P < 0.05) and albumen height (P < 0.01) reduced and were not significantly influenced by supplemental 80 mg/kg Zn-Met group until being stored 15 d as compared to the control. Zn-Met group in 100 mg/kg significantly increased haugh unit (P < 0.05) as compared to the control. The activity of MDA in serum had a linear decrease in 20 to 100 mg/kg Zn-Met. The activity of CAT in liver and GSH-Px in serum had quadratic effects in response to the Zn-Met treatments. Compared to the control, 60 mg/kg Zn-Met group increased the T-AOC, GSH-Px activity in serum (P < 0.01), and the T-AOC (P < 0.05), CuZnSOD (P < 0.01), GSH-Px (P < 0.01) activity in liver. Compared with the control, the concentration of serum ionic Ca in 80, 100 mg/kg Zn-Met treatments reduced (P < 0.01) significantly while the activity of serum alkaline phosphatase (AKP) increased in the Zn-Met groups of 40, 60, and 80 mg/kg (P < 0.01), and 100 mg/kg (P < 0.05). In conclusion, dietary Zn-Met supplementation at 60 to 80 mg/kg had more positive effects on performance, egg quality, and antioxidant capacity in laying hens as compared to 80 mg/kg ZnSO4.
Yu Ping Feng San (YPFS), a Chinese herbal decoction, is composed of Astragali Radix (AR; Huangqi), Atractylodis Macrocephalae Rhizoma (AMR; Baizhu) and Saposhnikoviae Radix (SR; Fangfeng) in a weight ...ratio of 1∶2∶1. Clinically, YPFS has been widely used to regulate immune functions; however, the action mechanism of it is not known. Here, we addressed this issue by providing detail analyses of chemical and biological properties of YPFS. By using rapid resolution liquid chromatography coupled with mass spectrometry, fifteen chemicals deriving from different herbs of YPFS were determined, and which served as a control for the standardization of the herbal extract of YPFS. In general, the amounts of chosen chemical markers were higher in a preparation of YPFS as compared to that of single herb or two-herb compositions. In order to reveal the immune functions of YPFS, the standardized extract was applied onto cultured murine macrophages. The treatment of YPFS stimulated the mRNA and protein expressions of pro-inflammatory cytokines via activation of NF-κB by enhancing IκBα degradation. In contrast, the application of YPFS suppressed the expressions of pro-inflammatory cytokines significantly in the lipopolysaccharide (LPS)-induced chronic inflammation model. In addition, YPFS could up regulate the phagocytic activity in cultured macrophages. These results therefore supported the bi-directional immune-modulatory roles of YPFS in regulating the releases of cytokines from macrophages.
We investigate a new laser-driven spherically convergent plasma fusion scheme (SCPF) that can produce thermonuclear neutrons stably and efficiently. In the SCPF scheme, laser beams of nanosecond ...pulse duration and 10^{14}-10^{15} W/cm^{2} intensity uniformly irradiate the fuel layer lined inside a spherical hohlraum. The fuel layer is ablated and heated to expand inwards. Eventually, the hot fuel plasmas converge, collide, merge, and stagnate at the central region, converting most of their kinetic energy to internal energy, forming a thermonuclear fusion fireball. With the assumptions of steady ablation and adiabatic expansion, we theoretically predict the neutron yield Y_{n} to be related to the laser energy E_{L}, the hohlraum radius R_{h}, and the pulse duration τ through a scaling law of Y_{n}∝(E_{L}/R_{h}^{1.2}τ^{0.2})^{2.5}. We have done experiments at the ShengGuangIII-prototype facility to demonstrate the principle of the SCPF scheme. Some important implications are discussed.
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