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31.
Cuicui Li Bingsheng Qin Yunfeng Zhang Alberto Varzi Stefano Passerini Jiaying Wang Jiaming Dong Danli Zeng Zhihong Liu Hansong Cheng 《Liver Transplantation》2019,9(10)
Herein, a novel electrospun single‐ion conducting polymer electrolyte (SIPE) composed of nanoscale mixed poly(vinylidene fluoride‐co‐hexafluoropropylene) (PVDF‐HFP) and lithium poly(4,4′‐diaminodiphenylsulfone, bis(4‐carbonyl benzene sulfonyl)imide) (LiPSI) is reported, which simultaneously overcomes the drawbacks of the polyolefin‐based separator (low porosity and poor electrolyte wettability and thermal dimensional stability) and the LiPF6 salt (poor thermal stability and moisture sensitivity). The electrospun nanofiber membrane (es‐PVPSI) has high porosity and appropriate mechanical strength. The fully aromatic polyamide backbone enables high thermal dimensional stability of es‐PVPSI membrane even at 300 °C, while the high polarity and high porosity ensures fast electrolyte wetting. Impregnation of the membrane with the ethylene carbonate (EC)/dimethyl carbonate (DMC) (v:v = 1:1) solvent mixture yields a SIPE offering wide electrochemical stability, good ionic conductivity, and high lithium‐ion transference number. Based on the above‐mentioned merits, Li/LiFePO4 cells using such a SIPE exhibit excellent rate capacity and outstanding electrochemical stability for 1000 cycles at least, indicating that such an electrolyte can replace the conventional liquid electrolyte–polyolefin combination in lithium ion batteries (LIBs). In addition, the long‐term stripping–plating cycling test coupled with scanning electron microscope (SEM) images of lithium foil clearly confirms that the es‐PVPSI membrane is capable of suppressing lithium dendrite growth, which is fundamental for its use in high‐energy Li metal batteries. 相似文献
32.
Lin Xiao Can Chen Zhendong Li Sumin Zhu Johan Ck Tay Xi Zhang Shijun Zha Jieming Zeng Wee Kiat Tan Xin Liu Wee Joo Chng Shu Wang 《Cytotherapy》2018,20(3):420-435
Vγ9Vδ2 T cells are a minor subset of lymphocytes in the peripheral blood that has been extensively investigated for their tolerability, safety and anticancer efficacy. A hindrance to the broad application of these cells for adoptive cellular immunotherapy has been attaining clinically appropriate numbers of Vγ9Vδ2 T cells. Furthermore, Vγ9Vδ2 T cells exist at low frequencies among cancer patients. We, therefore, sought to conceive an economical method that allows for a quick and robust large-scale expansion of Vγ9Vδ2 T cells. A two-step protocol was developed, in which peripheral blood mononuclear cells (PBMCs) from healthy donors or cancer patients were activated with Zometa and interleukin (IL)-2, followed by co-culturing with gamma-irradiated, CD64-, CD86- and CD137L-expressing K562 artificial antigen-presenting cells (aAPCs) in the presence of the anti-CD3 antibody OKT3. We optimized the co-culture ratio of K562 aAPCs to immune cells, and migrated this method to a G-Rex cell growth platform to derive clinically relevant cell numbers in a Good Manufacturing Practice (GMP)-compliant manner. We further include a depletion step to selectively remove αβ T lymphocytes. The method exhibited high expansion folds and a specific enrichment of Vγ9Vδ2 T cells. Expanded Vγ9Vδ2 T cells displayed an effector memory phenotype with a concomitant down-regulated expression of inhibitory immune checkpoint receptors. Finally, we ascertained the cytotoxic activity of these expanded cells by using nonmodified and chimeric antigen receptor (CAR)–engrafted Vγ9Vδ2 T cells against a panel of solid tumor cells. Overall, we report an efficient approach to generate highly functional Vγ9Vδ2 T cells in massive numbers suitable for clinical application in an allogeneic setting. 相似文献
33.
Ni Zeng Tao Wang Mei Chen Zhicheng Yuan Jiangyue Qin Yanqiu Wu Lijuan Gao Yongchun Shen Lei Chen Fuqiang Wen 《Journal of cellular and molecular medicine》2019,23(8):5532-5541
As a novel kind of non‐coding RNA, circular RNAs (circRNAs) were involved in various biological processes. However, the role of circRNAs in the developmental process of chronic obstructive pulmonary disease (COPD) is still unclear. In the present study, by using a cell model of COPD in primary human small airway epithelial cells (HSAECs) treated with or without cigarette smoke extract (CSE), we uncovered 4,379 previously unknown circRNAs in human cells and 903 smoke‐specific circRNAs, with the help of RNA‐sequencing and bioinformatic analysis. Moreover, 3,872 up‐ and 4,425 down‐regulated mRNAs were also identified under CSE stimulation. Furthermore, a putative circRNA‐microRNA‐mRNA network was constructed for in‐depth mechanism exploration, which indicated that differentially expressed circRNAs could influence expression of some key genes that participate in response to pentose phosphate pathway, ATP‐binding cassette (ABC) transporters, glycosaminoglycan biosynthesis pathway and cancer‐related pathways. Our research indicated that cigarette smoke had an influence on the biogenesis of circRNAs and mRNAs. CircRNAs might be involved in the response to CSE in COPD through the circRNA‐mediated ceRNA networks. 相似文献
34.
Matthias Wurm An-Ping Zeng 《Metabolomics : Official journal of the Metabolomic Society》2012,8(6):1081-1089
The quantification of metabolite leakage from damaged mammalian cells to the surrounding medium is of high interest for the processing of samples for metabolomic analysis. It is also of relevance to know the typical time span which is required for a promoted metabolite release through a selectively permeabilized cell membrane. The real-time observation of such a process is difficult since small metabolites cannot be observed directly by optical methods and other more indirect assays can disturb the metabolite concentration itself. However, the diffusion based loss of metabolites from the cytoplasm can be predicted on the basis of reference measurements taken from an easy-to-detect molecule with known diffusion coefficient. In this work, we use green fluorescent protein (GFP) as a marker and model its release from damaged cells using the finite-element method. A correlation between the disrupted membrane area fraction, A d , the distribution of membrane ruptures and the rate of GFP efflux, k e , has been established. k e has been determined experimentally for Chinese hamster ovary cells, which have been damaged mechanically by passage through a micronozzle geometry in a microfluidic system. The immediate GFP release downstream of the micronozzles has been observed in real-time and the corresponding membrane damage has been predicted. On this basis, we calculated the expected times required for the drainage of freely diffusable cytosolic glucose and found a loss of ??90% within 1 s for a disrupted membrane area fraction of ??5%. Hence, even minimal membrane damage would lead to a rapid loss of cytosolic metabolites by diffusion unless membrane resealing processes take place. 相似文献
35.
Yong-Ke You Wei-Feng Wu Xiao-Ru Huang Hai-Di Li Ye-Ping Ren Jin-Cheng Zeng Haiyong Chen Hui Yao Lan 《International journal of biological sciences》2021,17(14):3911
Introduction and Aims: Elevated plasma levels of C-reactive protein (CRP) are closely associated with progressive renal injury in patients with chronic kidney disease (CKD). Here, we tested a hypothesis that CRP may promote renal fibrosis and inflammation via a TGF-β/Smad3-dependent mechanism.Methods: Role and mechanisms of TGF-β/Smad3 in CRP-induced renal fibrosis and inflammation were examined in a mouse model of unilateral ureteral obstruction (UUO) induced in CRP Tg/Smad3 KO mice and in a rat tubular epithelial cell line in which Smad3 gene is stably knocked down (S3KD-NRK52E).Results: We found that mice overexpressing the human CRP gene were largely promoted renal inflammation and fibrosis as evidenced by increasing IL-1β, TNF-α, MCP-1 expression, F4/80+ macrophages infiltration, and marked accumulation of α-smooth muscle actin (α-SMA), collagen I and fibronectin in the UUO kidney, which were blunted when Smad3 gene was deleted in CRPtg-Smad3KO. Mechanistically, we found that the protection of renal inflammation and fibrosis in the UUO kidney of CRPtg-Smad3KO mice was associated with the inactivation of CD32-NF-κB and TGF-β/Smad3 signaling.Conclusion: In conclusion, Smad3 deficiency protects against CRP-mediated renal inflammation and fibrosis in the UUO kidney by inactivating CD32-NF-κB and TGF-β/Smad3 signaling. 相似文献
36.
Yang ZH Zeng R Yang G Wang Y Li LZ Lv ZS Yao M Lai B 《Journal of industrial microbiology & biotechnology》2008,35(9):1047-1051
As an important organic compound, chiral alcohols are the key chiral building blocks to many single enantiomer pharmaceuticals. Asymmetric reduction of the corresponding prochiral ketones to produce the chiral alcohols by biocatalysis is one of the most promising routes. Asymmetric reduction of different kinds of non-natural prochiral ketones catalyzed by various plants tissue was studied in this work. Acetophenone, 4'-chloroacetophenone and ethyl 4-chloroacetoacetate were chosen as the model substrates for simple ketone, halogen-containing aromatic ketone and beta-ketoesters, respectively. Apple (Malus pumila), carrot (Daucus carota), cucumber (Cucumis sativus), onion (Allium cepa), potato (Soanum tuberosum), radish (Raphanus sativus) and sweet potato (Ipomoea batatas) were chosen as the biocatalysts. It was found that these kinds of prochiral ketoness could be reduced by these plants tissue with high enantioselectivity. Both R- and S-form configuration chiral alcohols could be obtained. The e.e. and chemical yield could reach about 98 and 80% respectively for acetophenone and 4'-chloroacetophenone reduction reaction with favorable plant tissue. And the e.e. and yield for ethyl 4-chloroacetoacetate reduction reaction was about 91 and 45% respectively. 相似文献
37.
Stem cells have the ability to differentiate into a variety of cells to replace dead cells or to repair tissue. Recently, accumulating evidence indicates that mechanical forces, cytokines and other factors can influence stem cell differentiation into vascular smooth muscle cells (SMCs). In developmental process, SMCs originate from several sources, which show a great heterogenicity in different vessel walls. In adult vessels, SMCs display a less proliferative nature, but are altered in response to risk factors for atherosclerosis. Traditional view on SMC origins in atherosclerotic lesions is challenged by the recent findings that stem cells and smooth muscle progenitors contribute to the development of atherosclerotic lesions. Vascular progenitor cells circulating in human blood and the presence of adventitia in animals are recent discoveries, but the source of these cells is still unknown. The present review gives an update on the progress of stem cell and SMC research in atherosclerosis, and discusses possible mechanisms of stem/progenitor cell differentiation that contribute to the disease process. 相似文献
38.
39.
Sebastien Sart Chang Liu Eric Z. Zeng Chunhui Xu Yan Li 《Engineering in Life Science》2022,22(11):667
With the advancement in lineage‐specific differentiation from human pluripotent stem cells (hPSCs), downstream cell separation has now become a critical step to produce hPSC‐derived products. Since differentiation procedures usually result in a heterogeneous cell population, cell separation needs to be performed either to enrich the desired cell population or remove the undesired cell population. This article summarizes recent advances in separation processes for hPSC‐derived cells, including the standard separation technologies, such as magnetic‐activated cell sorting, as well as the novel separation strategies, such as those based on adhesion strength and metabolic flux. Specifically, the downstream bioprocessing flow and the identification of surface markers for various cell lineages are discussed. While challenges remain for large‐scale downstream bioprocessing of hPSC‐derived cells, the rational quality‐by‐design approach should be implemented to enhance the understanding of the relationship between process and the product and to ensure the safety of the produced cells. 相似文献
40.
贵州产五步蛇蛇毒磷脂酶A2的抗凝血及抗血栓作用研究 总被引:1,自引:0,他引:1
目的研究贵州产五步蛇蛇毒磷脂酶A2的抗凝血及抗血栓作用。方法对大鼠静脉注射不同剂量的PLA2,测定大鼠的凝血时间、凝血酶原时间、抗凝效价和血栓抑制率。结果PLA2浓度达到1.0mg/kg以上,能显著延长大鼠凝血时间及凝血酶原时间,其抗凝效价相当于肝素钠的24.8%~31.5%。PLA2能显著抑制大鼠实验性动脉及静脉血栓的形成。结论贵州产五步蛇PLA2具有较强的抗凝血和抗血栓作用。 相似文献