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Previous studies have suggested that immune system development and weaning stress are closely related to the maturation of gut microbiota. The early-life period is a “window of opportunity” for microbial colonization, which potentially has a critical impact on the development of the immune system. Fecal microbiota transplantation (FMT) and probiotics are often used to regulate gut microbial colonization. This study aims to test whether early intervention with FMT using fecal microbiota from gestation sows combined with Clostridium butyricum and Saccharomyces boulardii (FMT-CS) administration could promote the maturation of gut microbiota and development of immune system in piglets. Piglets were assigned to control (n = 84) and FMT-CS treatment (n = 106), which were treated with placebo and bacterial suspension during the first three days after birth, respectively. By 16S rRNA gene sequencing, we found that FMT-CS increased the α-diversity and reduced the unweighted UniFrac distances of the OTU community. Besides, FMT-CS increased the relative abundance of beneficial bacteria, while decreasing that of opportunistic pathogens. FMT-CS also enhanced the relative abundance of genes related to cofactors and vitamin, energy, and amino acid metabolisms during the early-life period. ELISA analysis revealed that FMT-CS gave rise to the plasma concentrations of IL-23, IL-17, and IL-22, as well as the plasma levels of anti-M.hyo and anti-PCV2 antibodies. Furthermore, the FMT-CS-treated piglets showed decreases in inflammation levels and oxidative stress injury, and improvement of intestinal barrier function after weaning as well. Taken together, our results suggest that early-life intervention with FMT-CS could promote the development of innate and adaptive immune system and vaccine efficacy, and subsequently alleviate weaning stress through promoting the maturation of gut microbiota in piglets. [ABSTRACT FROM AUTHOR]

Early intervention with fecal microbiota transplantation (FMT) improves the growth performance and intestinal barrier function of piglets. Accelerating intestinal oxygen concentration is beneficial for symbiotic bacterial colonization. Saccharomyces boulardii (SB) is an aerobic fungus, which may contribute to the colonization of anaerobic symbiotic bacteria by competing for oxygen. Clostridium butyricum (CB) improves intestinal barrier function and performance, via regulating the gut microbiota composition of piglets. The objective of this study was to investigate the effect of early intervention with FMT combining CB and SB on growth performance, diarrhea, and intestinal barrier function in piglets. A total of 77 litters of neonatal piglets assigned to one of six treatments, which treated with antibiotics (AB), placebo (CON), and FMT (FMT), FMT-added CB (FMT+C), FMT-added SB (FMT+S), and FMT-added CB and SB (FMT+C+S), respectively. FMT+C+S treated piglets had higher body weight (BW) and average daily gain (ADG) both in weaning and finial period, and it significantly increased the levels of fecal mucin-2 (MUC2), fecal short-chain fatty acids (SCFAs), and relative abundance of fecal Lactobacillus spp., and Bifidobacterium genus. Moreover, early intervention with FMT+C+S reduced the diarrhea rate during the experiment. FMT+C+S also decreased the level of plasma diamine oxidase (DAO) and D-lactate (D-LA), and relative abundance of fecal E. coli during the suckling period. In summary, early intervention with FMT combining CB and SB improved the growth performance, intestinal barrier function, fecal SCFAs concentration, and fecal Lactobacillus and Bifidobacterium of piglets. [ABSTRACT FROM AUTHOR]

The routine spermidine (SPD) detection method is time-consuming and laborious due to the lengthy chromatographic separation and/or tedious sample derivatization pretreatment. In this study, direct analysis in real-time ionization mode coupled with mass spectrometry (DART-MS) was developed to rapidly determine the SPD content of 12 bean cultivars. The results were compared in detail with those of the classical UHPLC-ESI-QTOF method. After conducting a series of optimizations, a simple sample extraction procedure employing 80% aqueous methanol, was followed by determination of sample extracts directly without any chromatographic separation or prior derivatization. The validated method showed excellent performance with low limits of detection (LOD of 0.025 mg⋅kg-1) and good recovery rates (102.79-148.44%). The investigation highlighted that the DART-MS method (~1.3 min per three samples) could be used as a high-throughput alternative to the classic UHPLC-ESI-QTOF method (~15 min per three samples). [ABSTRACT FROM AUTHOR]

This paper discusses the tracking coordination of a linear switched reluctance machine (LSRM) network based on a global feedback control strategy with a full-state observation framework. The observer is allocated on the follower instead of the leader to form a leader--follower--observer network, by utilizing the leader as the global feedback tracking controller and the observer as the observation of the full states. The internal model compensator (IMC) is applied to the leader for the improvement of the network performance. The full-state information of the LSRM network is reconfigured by the output of the LSRM where the observer is located to provide necessary feedback information to the leader. Then, the controllability and observability of the leader--follower--observer network with the IMC are inspected, serving as a basis for the design of the global controller with the IMC and full-state observer. Experimentation verifies the effectiveness of the proposed network control scheme and the results demonstrate that both the absolute and the relative accuracy can be simultaneously improved, compared to the LSRM network with only the consensus algorithm and no global feedback mechanism. [ABSTRACT FROM AUTHOR]

This paper investigates the controllability of a closed-loop tracking synchronization network based on multiple linear-switched reluctance machines (LSRMs). The LSRM network is constructed from a global closed-loop manner, and the closed loop only replies to the input and output information from the leader node. Then, each local LSRM node is modeled as a general second-order system, and the model parameters are derived by the online system identification method based on the least square method. Next, to guarantee the LSRM network's controllability condition, a theorem is deduced that clarifies the relationship among the LSRM network's controllability, the graph controllability of the network and the controllability of the node dynamics. A state feedback control strategy with the state observer located on the leader is then proposed to improve the tracking performance of the LSRM network. Last, both the simulation and experiment results prove the effectiveness of the network controller design scheme and the results also verify that the leader-based global feedback strategy not only improves the tracking performance but also enhances the synchronization accuracy of the LSRM network experimentally. [ABSTRACT FROM AUTHOR]

This paper investigates a distributed, coordinated motion control network based on multiple direct-drive, linear switched reluctance machines (LSRMs). A hierarchical, two-level synchronization control strategy is proposed for the four LSRMs based motion control network. The high-level, reference signals agreement algorithm is first employed to correct the asynchronous behaviors of the position commands. Then, the low-level tracking synchronization method is applied for the collaborative position control of the four LSRMs. The proposed two-level, fault-tolerant control strategy eliminates the asynchrony of the reference signals and it also guarantees the coordinated tracking control performance of the four LSRMs. Experimental results demonstrate that effective coordinated tracking control can be ensured, based on the successful agreement of reference signals and an absolute tracking error falling within 2 mm can be achieved. [ABSTRACT FROM AUTHOR]

Lower extremity varicose veins are a common condition in vascular surgery and proliferation of vascular smooth muscle cells (VSMCs) in the intima is a significant pathological feature of varicosity. However, the pathogenesis of varicose veins is not fully understood. Osteopontin (OPN) could promote the migration and adhesion of VSMCs through the cell surface receptor integrin ß3 and the cooperation of OPN and integrin ß3 is involved in many vascular diseases. However, the role of OPN and integrin ß3 in varicosity remains unclear. In the current study, we found that the methylation levels in the promoter regions of OPN and integrin ß3 genes in the VSMCs of varicose veins are reduced and the protein expression of OPN and integrin ß3 are increased, compared with normal veins. Furthermore, it was observed that VSMCs in the neointima of varicose veins were transformed into the synthetic phenotype. Collectively, hypomethylation of the promoter regions for OPN and integrin ß3 genes may increase the expression of these genes in varicosity, which is closely related to VSMC phenotype switching. Hypomethylation of the promoter regions for OPN and integrin ß3 genes may be a key factor in the pathogenesis of varicosity. [ABSTRACT FROM AUTHOR]