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971.
972.
Excessive neutrophil extracellular trap (NET) formation may contribute to polymyositis (PM)‐associated interstitial lung diseases (ILD), but the underlying mechanism is not fully revealed. In this study, we found that NET accelerated the progression of ILD and promoted pulmonary fibrosis (PF) in vivo. miR‐7 expression was down‐regulated in lung tissue of PM group than control group, and NETs further decreased miR‐7 expression. TLR9 and Smad2 were up‐regulated in lung tissue of PM group than control group, and NETs further increased TLR9 and Smad2 expressions. In vitro experiments showed that PMA‐treated NETs accelerated the proliferation of LF and their differentiation into myofibroblast (MF), whereas DNase I decreased the promotion effect of NETs. Neutrophil extracellular trap components myeloperoxidase (MPO) and histone 3 also promoted the proliferation and differentiation of LF. In addition, we demonstrated that TLR9 involved in the regulation of NETs on LF proliferation and differentiation, and confirmed the interaction between miR‐7 and Smad2 in LF. Finally, miR‐7‐Smad2 pathway was confirmed to be involved in the regulation of TLR9 on LF proliferation and differentiation. Therefore, NETs promote PM‐related ILD, and TLR9‐miR‐7‐Smad2 signalling pathway is involved in the proliferation of LFs and their differentiation into MFs.  相似文献   
973.
974.
Pathogenesis and treatment for diabetic neuropathy are still complex. A deficit of neurotrophic factors affecting Schwann cells is a very important cause of diabetic neuropathy. Neuritin is a newly discovered potential neurotrophic factor. In this study, we explored the effect of exogenous neuritin on survivability and functions of diabetic Schwann cells of rats with experimental diabetic neuropathy. Diabetic neuropathy was induced in rats. 12‐week diabetic rats contrasted with non‐diabetic normal rats had decreased levels of serum neuritin and slowed nerve conduction velocities (NCVs). Schwann cells isolated from these diabetic rats and cultured in high glucose showed reduced cell neuritin mRNA and protein and supernatant neuritin protein, increased apoptosis rates, increased caspase‐3 activities and progressively reduced viability. In contrast, exogenous neuritin treatment reduced apoptosis and improved viability, with elevated Bcl‐2 levels (not Bax) and decreased caspase‐3 activities. Co‐cultured with diabetic Schwann cells pre‐treated with exogenous neuritin in high glucose media, and diabetic DRG neurons showed lessened decreased neurite outgrowth and supernatant NGF concentration occurring in co‐culture of diabetic cells. Exogenous neuritin treatment ameliorated survivability and functions of diabetic Schwann cells of rats with diabetic neuropathy. Our study may provide a new mechanism and potential treatment for diabetic neuropathy.  相似文献   
975.
Sepsis‐associated encephalopathy (SAE) has typically been associated with a poor prognosis. Although sestrin 2 (SESN2) plays a crucial role in metabolic regulation and the stress response, its expression and functional roles in SAE are still unclear. In the present study, SAE was established in mice through caecal ligation and puncture (CLP). The adeno‐associated virus 2 (AAV2)‐mediated SESN2 expression (ie overexpression and knockdown) system was injected into the hippocampi of mice with SAE, and subsequently followed by electron microscopic analysis, the Morris water maze task and pathological examination. Our results demonstrated an increase of SESN2 in the hippocampal neurons of mice with SAE, 2‐16 hours following CLP. AAV2‐mediated ectopic expression of SESN2 attenuated brain damage and loss of learning and memory functions in mice with SAE, and these effects were associated with lower pro‐inflammatory cytokines in the hippocampus. Mechanistically, SESN2 promoted unc‐51‐like kinase 1 (ULK1)‐dependent autophagy in hippocampal neurons through the activation of the AMPK/mTOR signalling pathway. Finally, AMPK inhibition by SBI‐0206965 blocked SESN2‐mediated attenuation of SAE in mice. In conclusion, our findings demonstrated that SESN2 might be a novel pharmacological intervention strategy for SAE treatment through promotion of ULK1‐dependent autophagy in hippocampal neurons.  相似文献   
976.
There are many different types of cardiovascular diseases, which impose a huge economic burden due to their extremely high mortality rates, so it is necessary to explore the underlying mechanisms to achieve better supportive and curative care outcomes. Sphingosine 1‐phosphate (S1P) is a bioactive lipid mediator with paracrine and autocrine activities that acts through its cell surface S1P receptors (S1PRs) and intracellular signals. In the circulatory system, S1P is indispensable for both normal and disease conditions; however, there are very different views on its diverse roles, and its specific relevance to cardiovascular pathogenesis remains elusive. Here, we review the synthesis, release and functions of S1P, specifically detail the roles of S1P and S1PRs in some common cardiovascular diseases, and then address several controversial points, finally, we focus on the development of S1P‐based therapeutic approaches in cardiovascular diseases, such as the selective S1PR1 modulator amiselimod (MT‐1303) and the non‐selective S1PR1 and S1PR3 agonist fingolimod, which may provide valuable insights into potential therapeutic strategies for cardiovascular diseases.  相似文献   
977.
978.
Although the diagnosis and therapy approach developed, techniques for the early diagnosis of HCC remain insufficient which results in poor prognosis of patients. The traditional biomarker AFP, however, has been proved with low specificity. Circulating exosomal ncRNAs revealed different profiles reflecting the characteristics of tumour. In this study, we mainly focused on circulating exosomal ncRNAs which might be the fingerprint for HCC, especially for the diagnosis or metastasis prediction. A high throughput lncRNA microarray in exosomes extracted from cell‐free plasma was applied. The risk score analysis was employed to screen the potential exosome‐derived lncRNAs in two independent sets based on different clinical parameters in 200 paired HCC patients. After a multi‐stage validation, we finally revealed three lncRNAs, ENSG00000248932.1, ENST00000440688.1 and ENST00000457302.2, increased in HCC comparing with the both chronic hepatitis (CH) patients and cancer‐free controls. ROC curve revealed a higher sensitivity and specificity in predicting the occurrence of HCC from cancer‐free controls and CH patients with the area under curve (AUC) of 0.905 and 0.879 by combining AFP. The three lncRNA panel combined with AFP also indicted a fingerprint function in predicting the metastasis of HCC with the AUC of 0.870. In conclusion, ENSG00000248932.1, ENST00000440688.1 and ENST00000457302.2 might be the potential biomarker for the tumorigenesis prediction from CH patients or healthy controls and may also be applied for dynamic monitoring the metastasis of HCC.  相似文献   
979.
Heteroatom doping is widely recognized as an appealing strategy to break the capacitance limitation of carbonaceous materials toward sodium storage. However, the concrete effects, especially for heteroatomic phase transformation, during the sodium storage reaction remain a confusing topic. Here, a novel hypercrosslinked polymerization approach is demonstrated to fabricate pyrrole/thiophene hypercrosslinked microporous copolymer and further give porous carbonaceous materials with accurately regulated N/S dual doping corresponding to starting feeding ratios. Significantly, the N doping contributes to the conductivity and surface wettability, while the S doping is bridged to build stable active sites, which can be electrochemically converted into mercaptan anions via faraday reaction and further enhancing reversible capacities. Meanwhile, the abundant S doping can also conduce to the expanded interlayer spacing to shorten the ions diffusion distance, thus optimizing the reaction kinetic. As a result, the N0.2S0.8‐micro‐dominant porous carbon delivers the highest reversible capacity of 521 mAh g?1 at 100 mA g?1 and excellent cyclic stability over 2000 cycles at 2000 mA g?1 with a capacity decay of 0.0145 mAh g?1 per cycle. This work is anticipated to provide an in‐depth understanding of capacitance contribution and illuminate the heteroatomic phase transformation during sodium storage reactions for doping carbonaceous anodes.  相似文献   
980.
Lithium–sulfur batteries are a promising high energy output solution for substitution of traditional lithium ion batteries. In recent times research in this field has stepped into the exploration of practical applications. However, their applications are impeded by cycling stability and short life‐span mainly due to the notorious polysulfide shuttle effect. In this work, a multifunctional sulfur host fabricated by grafting highly conductive Co3Se4 nanoparticles onto the surface of an N‐doped 3D carbon matrix to inhibit the polysulfide shuttle and improve the sulfur utilization is proposed. By regulating the carbon matrix and the Co3Se4 distribution, N‐CN‐750@Co3Se4‐0.1 m with abundant polar sites is experimentally and theoretically shown to be a good LiPSs absorbent and a sulfur conversion accelerator. The S/N‐CN‐750@Co3Se4‐0.1 m cathode shows excellent sulfur utilization, rate performance, and cyclic durability. A prolonged cycling test of the as‐fabricated S/N‐CN‐750@Co3Se4‐0.1 m cathode is carried out at 0.2 C for more than 5 months which delivers a high initial capacity of 1150.3 mAh g?1 and retains 531.0 mAh g?1 after 800 cycles with an ultralow capacity reduction of 0.067% per cycle, maintaining Coulombic efficiency of more than 99.3%. The reaction details are characterized and analyzed by ex situ measurements. This work highly emphasizes the potential capabilities of transition‐metal selenides in lithium–sulfur batteries.  相似文献   
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