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71.
胶质母细胞瘤(glioblastoma,GBM)因组织学异质性、侵袭能力强、术后复发快等问题,致使患者经手术治疗、化疗和放疗后的预后差,总体生存期短。GBM细胞来源外泌体(GBM cell-derived exosome,GBM-exo)能够通过其携带的细胞因子、miRNA、DNA和蛋白质等调节GBM细胞的增殖和迁移,通过血管生成蛋白和非编码RNA促进肿瘤血管生成,通过调节因子、蛋白质和药物靶向免疫检查点等介导肿瘤免疫逃逸,以及通过非编码RNA对抗GBM细胞的耐药性,有望成为个性化治疗GBM的重要靶标,且可以作为GBM的诊断和预后标志物。本文阐述了GBM-exo的制备方法和生物学特征,及其在GBM细胞增殖、血管生成、免疫逃逸和耐药性方面的作用和分子机制,为研发诊治GBM的新策略提供参考。  相似文献   
72.
The elimination of transformed and viral infected cells by natural killer (NK) cells requires a specialized junction between NK and target cells, denominated immunological synapse (IS). After initial recognition, the IS enables the directed secretion of lytic granules content into the susceptible target cell. The lymphocyte function-associated antigen (LFA)-1 regulates NK effector function by enabling NK-IS assembly and maturation. The pathways underlying LFA-1 accumulation at the IS in NK cells remained uncharacterized. A kinase anchoring protein 350 (AKAP350) is a centrosome/Golgi-associated protein, which, in T cells, participates in LFA-1 activation by mechanisms that have not been elucidated. We first evaluated AKAP350 participation in NK cytolytic activity. Our results showed that the decrease in AKAP350 levels by RNA interference (AKAP350KD) inhibited NK-YTS cytolytic activity, without affecting conjugate formation. The impairment of NK effector function in AKAP350KD cells correlated with decreased LFA-1 clustering and defective IS maturation. AKAP350KD cells that were exclusively activated via LFA-1 showed impaired LFA-1 organization and deficient lytic granule translocation as well. In NK AKAP350KD cells, activation signaling through Vav1 was preserved up to 10 min of interaction with target cells, but significantly decreased afterwards. Experiments in YTS and in ex vivo NK cells identified an intracellular pool of LFA-1, which partially associated with the Golgi apparatus and, upon NK activation, redistributed to the IS in an AKAP350-dependent manner. The analysis of Golgi organization indicated that the decrease in AKAP350 expression led to the disruption of the Golgi integrity in NK cells. Alteration of Golgi function by BFA treatment or AKAP350 delocalization from this organelle also led to impaired LFA-1 localization at the IS. Therefore, this study characterizes AKAP350 participation in the modulation of NK effector function, revealing the existence of a Golgi-dependent trafficking pathway for LFA-1, which is relevant for LFA-1 organization at NK-lytic IS.  相似文献   
73.
Paul Little  Li Hsu  Wei Sun 《Biometrics》2023,79(3):2705-2718
Somatic mutations in cancer patients are inherently sparse and potentially high dimensional. Cancer patients may share the same set of deregulated biological processes perturbed by different sets of somatically mutated genes. Therefore, when assessing the associations between somatic mutations and clinical outcomes, gene-by-gene analysis is often under-powered because it does not capture the complex disease mechanisms shared across cancer patients. Rather than testing genes one by one, an intuitive approach is to aggregate somatic mutation data of multiple genes to assess their joint association with clinical outcomes. The challenge is how to aggregate such information. Building on the optimal transport method, we propose a principled approach to estimate the similarity of somatic mutation profiles of multiple genes between tumor samples, while accounting for gene–gene similarities defined by gene annotations or empirical mutational patterns. Using such similarities, we can assess the associations between somatic mutations and clinical outcomes by kernel regression. We have applied our method to analyze somatic mutation data of 17 cancer types and identified at least five cancer types, where somatic mutations are associated with overall survival, progression-free interval, or cytolytic activity.  相似文献   
74.
Influenza A viruses (IAV) have been the cause of several influenza pandemics in history and are a significant threat for the next global pandemic. Hospitalized influenza patients often have excess interferon production and a dysregulated immune response to the IAV infection. Obtaining a better understanding of the mechanisms of IAV infection that induce these harmful effects would help drug developers and health professionals create more effective treatments for IAV infection and improve patient outcomes. IAV stimulates viral sensors and receptors expressed by alveolar epithelial cells, like RIG-I and toll-like receptor 3 (TLR3). These two pathways coordinate with one another to induce expression of type III interferons to combat the infection. Presented here is a queuing theory-based model of these pathways that was designed to analyze the timing and amount of interferons produced in response to IAV single stranded RNA and double-stranded RNA detection. The model accurately represents biological data showing the necessary coordination of the RIG-I and TLR3 pathways for effective interferon production. This model can serve as the framework for future studies of IAV infection and identify new targets for potential treatments.  相似文献   
75.
Adeno-associated virus (AAV)-based gene therapy holds promise as a fundamental treatment for genetic disorders. For clinical applications, it is necessary to control AAV release timing to avoid an immune response to AAV. Here we propose an ultrasound (US)-triggered on-demand AAV release system using alginate hydrogel microbeads (AHMs) with a release enhancer. By using a centrifuge-based microdroplet shooting device, the AHMs encapsulating AAV with tungsten microparticles (W-MPs) are fabricated. Since W-MPs work as release enhancers, the AHMs have high sensitivity to the US with localized variation in acoustic impedance for improving the release of AAV. Furthermore, AHMs were coated with poly-l -lysine (PLL) to adjust the release of AAV. By applying US to the AAV encapsulating AHMs with W-MPs, the AAV was released on demand, and gene transfection to cells by AAV was confirmed without loss of AAV activity. This proposed US-triggered AAV release system expands methodological possibilities in gene therapy.  相似文献   
76.
77.
IntroductionPerson-centered care (PCC) includes life story, a form of reminiscence therapy that can be useful in the treatment of dementia. We compared the efficacy of using a digital or conventional life story book (LSB) on depressive symptoms, communication, cognition, and quality of life.Material and methodsThirty one persons with dementia living in 2 PCC nursing homes were randomly assigned to receive reminiscence therapy based on the Neural Actions digital LSB (n = 16) or a conventional LSB (n = 15). Both groups performed 2 weekly sessions of 45 min for 5 weeks. Depressive symptoms were evaluated with the Cornell scale (CSDD); communication with the Holden scale (HCS), cognition with the Mini Mental State Examination (MMSE) and quality of life with the quality of life scale for Alzheimer's (QoL-AD). The results were analyzed using ANOVA of repeated measures with the jamovi 2.3 program.ResultsBoth LSB improved communication skills (η2 = 0.115; p < 0.001), with no differences between groups. No effects on quality of life, cognition, or mood were found.ConclusionsIn PCC centres digital or conventional LSB can be useful in the treatment of people with dementia by facilitating communication. Its role on quality of life, cognition or mood is uncertain.  相似文献   
78.
Five patients with common variable immunodeficiency treated in our hospital between December 1979 and December 1990 were given six kinds of intravenous immunoglobulin preparations (pepsin treated, S-sulfonated, polyethylene glycol treated, pH4 treated, alkylated, and pH4.25 formulation preparation) for replacement therapy. Duration of the therapy ranged from 7.6 to 11 years. Incidences of fever and acute infections were variable among patients, but no significant differences were seen in the incidences among periods given each preparation. Three cases revealed abnormal pulmonary functions in tests. Adverse reactions were rarely seen in our study periods, and no severe reactions were observed. No significant differences were seen in incidences of adverse reactions. Postinfusion levels of serum complement slightly decreased from preinfusion levels. However, the decrease in complement was not related to any adverse reaction. No long-term complications such as transmission of hepatitis have been observed. Our data suggest that no obvious differences exist between the efficacy and safety of each IVIG preparation. Differences of efficacy of IVIG replacement therapy may be due to the variable pathophysiology of each patient.Abbreviations CVID common variable immunodeficiency - IVIG intravenous immunoglobulin  相似文献   
79.
本研究旨在探究非洲猪瘟病毒(African swine fever virus, ASFV) I226R蛋白(I226R protein, pI226R)抑制cGAS-STING信号通路的作用机制。利用双荧光素酶报告系统和实时荧光定量PCR (real-time quantitative PCR, qPCR)证明pI226R显著抑制cGAS-STING通路介导的I型干扰素及干扰素刺激相关基因的产生。免疫共沉淀及激光共聚焦显微镜试验发现pI226R与cGAS蛋白相互作用。免疫印迹分析证明pI226R通过自噬-溶酶体途径促进cGAS蛋白的降解。同时,pI226R阻碍了cGAS与E3泛素连接酶三基序蛋白56 (tripartite motif protein 56, TRIM56)的结合,导致cGAS的单泛素化减弱,从而抑制了cGAS的活化和cGAS-STING通路的激活。总之,本研究证明ASFV pI226R通过拮抗cGAS进而抑制宿主的抗病毒天然免疫反应,进一步增加了对研究ASFV免疫逃逸机制的理解,为疫苗的研发提供了理论基础。  相似文献   
80.
实验研究了三疣梭子蟹(Portunus trituberculatus)卵巢发育过程中(Ⅰ—V期)组织色泽、类胡萝卜素组成与含量、抗氧化和非特异性免疫指标的变化规律,进一步探讨了肝胰腺中类胡萝卜素含量变化与抗氧化指标的关系。结果表明:(1)卵巢发育期间,卵巢指数(GSI)显著增加(P<0.05),肝胰腺指数(HSI)整体呈先升后降的趋势;卵巢的红度(a*)值和黄度(b*)值、肝胰腺的亮度(L*)值和b*值均呈显著上升趋势,但卵巢中L*值呈下降趋势。(2)在卵巢发育过程中,卵巢中的总类胡萝卜素、虾青素、叶黄素和β-胡萝卜素含量均为先升后降的趋势,虾青素含量在Ⅳ期最高;肝胰腺中的虾青素含量呈上升趋势,而β-胡萝卜素含量为显著下降趋势;内表皮中的总类胡萝卜素、虾青素、叶黄素、海胆烯酮和β-胡萝卜素含量均呈现下降趋势;就不同组织中类胡萝卜素含量而言,内表皮中虾青素含量最高。卵巢和肝胰腺的L*值与总类胡萝卜素含量呈显著负相关,卵巢的a*值和b*值均与总类胡萝卜素、虾青素、叶黄素、海胆烯酮和β-胡萝卜素含量呈显著正相关。肝胰腺的a*值与各类胡萝卜素含量无显著相关性, b*值仅与虾青素含量呈显...  相似文献   
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