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This study was performed to investigate the inhibitory mechanisms of 3 plant polyphenols, grape seed extract (GSE), lotus seed proanthocyanidins (LSPC) and lotus root polyphenol extract (LRPE), against Shewanella putrefaciens. Their antibacterial effects were determined in terms of minimum inhibitory concentration (MIC) and the growth curve of S. putrefaciens. By scanning electron microscopy (SEM), relative conductivity, propyridine iodide (PI) staining, alkaline phosphatase (AKP) activity, extracellular protein content, nucleic acid leakage, Na+ K+ -ATPase activity and membrane protein fluorescence analysis, the antibacterial mechanism was explored. The results showed that the MICs of GSE, LRPE and LSPC were 31.25, 62.25 and 125.00 μg/mL, respectively. After S. putrefaciens was treated with the polyphenols, the position of membrane proteins was changed, the fluorescence intensity was reduced, the morphology was altered, the surface became wrinkled and sunken, and the growth was significantly inhibited. In addition, the activity of extracellular AKP, the contents of nucleic acid and extracellular protein in the bacterial suspension, relative conductivity and PI intake were significantly increased, and Na+ K+-ATPase was inactivated to a certain extent, thereby leading to cell death.

Chitosan nanoparticle is becoming an excellent carrier for the delivery of bioactive components due to the advantages of simple preparation, low cost and high biocompatibility. Previous studies have shown that chitosan/sodium tripolyphosphate (CS/TPP) and chitosan/flaxseed gum (CS/FG) nanoparticles loaded with bighead carp peptides (BCP) have the advantages of small particle size, high encapsulation rate and significant slow-release effect. This study explored the effects of ionic strength, pH, simulated digestion and storage time on the preparation of chitosan/sodium tripolyphosphate (CS/TPP-BCP) and chitosan/flaxseed gum (CS/FG-BCP) nanoparticles, and evaluated the extracellular lactate dehydrogenase content and antioxidant capacity in vivo of Caco-2 cells treated with the chitosan nanoparticles and their cellular uptake. The results showed that the two kinds of chitosan nanoparticles were stable under acidic conditions and sensitive to a solution with opposite charges. The stability of the nanoparticles loaded with bighead peptides was higher than that of free peptides and both nanoparticles showed higher biocompatibility and cell uptake.

With the transformation and development of China's economy and society, the state attaches great importance to the equalization of public services to meet the growing demand for a better life. Museums are not only one of the most important needs of people's spiritual culture but are also an important part of the public cultural service system. Their reasonable layout has an important impact on the equalization of basic public services. Therefore, research on the temporal and spatial evolution of museums has become one of the hotspots of related disciplines, and is of great significance to deepen the basic public service theory. This study selects a list of museums from 1990 to 2018 and uses a nuclear density analysis, standard deviation ellipse, spatial autocorrelation, and geographic detector model, to analyze the evolution trend of museum quantity, evolution characteristics of spatial distribution mode, law of spatial differentiation, and influencing factors of the temporal and spatial distribution of the museums. The results show that: 1) in terms of quantity evolution trend, there are significant differences in the number of museums from 1990-2000, 2000-2010, and 2010-2018, with a gradual increase in the number. Overall, the number of museums showed an accelerated growth trend from 1990-2018. The differences between the East and West are obvious. The number of museums in the eastern region is dense and the development is rapid; contrastingly, the number of museums in the central and western regions is sparse and development is relatively slow. 2) In terms of the evolution of spatial distribution mode, over time, Chinese museums continue to gather spatially and gradually evolve from "single center" distribution mode to "multi center" distribution mode, and the degree of agglomeration continues to improve. 3) The standard deviation ellipse analysis shows that from 1990-2018, the center of gravity of the Chinese museums was always located in the East; the center of gravity shifted slightly over time, and the moving track was about "Z." 4) In terms of the spatial differentiation law, there has been a significant spatial agglomeration process of Chinese museums since 1990, forming a pattern of "hot in the East and cold in the west". The middle and lower reaches of the Yangtze River are the hotspots of Chinese museums, and Xinjiang and Tibet are always in the cold spots. Additionally, the scope of hotspots continues to expand annually, extending to the northwest inland, which is consistent with China's strategy of "equalization of public cultural services" in recent years; it is also conducive to breaking the layout of public cultural facilities that are "strong in the East and weak in the West." 5) In terms of influencing factors, museum spatial differentiation is the result of the comprehensive action of multiple factors, which is mainly affected by the economy, society, policy, culture, and education. Among them, policy, cultural, and educational factors are the main influencing factors of museum spatial differentiation, followed by social factors, and economic factors are the general factors affecting its distribution.

Neutrophil extracellular traps (NETs) are characterized by a extracellular fibrous network structure produced by neutrophils with DNA and proteins. NETs can be formed by NADPH-dependent NETosis and NADPH-independent NETosis. After formation, it is not only hydrolyzed by DNase in plasma but can also be degraded intracellularly and extracellularly by macrophages and dendritic cells. Recent researches on NETs have reported the increased expression of NETs in a variety of hematological diseases and its immunomodulatory effect on blood system diseases. For example, NETs are closely linked to infections related to leukemia treatment, which affects the treatment and prognosis of leukemia; NETs are also involved in the progression of multiple myeloma, promote the progression of diffuse large B-cell lymphoma, and mediate the thrombotic events of chronic myeloproliferative tumors.

Objective: To explore the immuno-effect of plasmacytoid dendritic cells (pDC) on bacteria infection induced spontaneous remission (SR) of leukemia., Methods: Both pDC and myeloid dendritic cells (mDC) were isolated and purified from leukemic patient with SR and healthy donor by combination of immunomagnetic beads and flow cytometry. pDC were cultured in RPMI1640 medium and stimulated with different bacteria. The T cells proliferation was detected by MTT, and cytokine production by ELISA kits., Results: The human bacterial pathogen Staphylococcus aureus and Pseudomonas aeruginosa stimulation for 48 h resulted in the maturation of pDC with production of high quantity of IFN-α at (15.34 ± 2.91) ng/ml and (10.38 ± 1.41) ng/ml, respectively, comparing with that of negative group at (1.36 ± 0.13) ng/ml (P<0.01). Activated pDC could promote the differentiation of naive CD4⁺ T cells to Th1 cells with secretion of IFN-γ at (2.16 ± 0.37) ng/ml and (2.73 ± 1.11) ng/ml, respectively, comparing with that of positive control at (2.55 ± 0.23) ng/ml (P > 0.05). Activated pDC showed higher T cell stimulatory capacities [proliferation index (PI) was 4.36 and 4.05, respectively] than that of non-activated pDC (PI was 1.23 and 0.13, respectively) (P < 0.01)., Conclusion: Staphylococcus aureus and Pseudomonas aeruginosa activated pDC may play a key role in SR of leukemia following severe infections.