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21.
Peripheral arterial disease (PAD) of the lower extremities is a chronic illness predominantly of atherosclerotic aetiology, associated to traditional cardiovascular (CV) risk factors. It is one of the most prevalent CV conditions worldwide in subjects >65 years, estimated to increase greatly with the aging of the population, becoming a severe socioeconomic problem in the future. The narrowing and thrombotic occlusion of the lower limb arteries impairs the walking function as the disease progresses, increasing the risk of CV events (myocardial infarction and stroke), amputation and death. Despite its poor prognosis, PAD patients are scarcely identified until the disease is advanced, highlighting the need for reliable biomarkers for PAD patient stratification, that might also contribute to define more personalized medical treatments. In this review, we will discuss the usefulness of inflammatory molecules, matrix metalloproteinases (MMPs), and cardiac damage markers, as well as novel components of the liquid biopsy, extracellular vesicles (EVs), and non-coding RNAs for lower limb PAD identification, stratification, and outcome assessment. We will also explore the potential of machine learning methods to build prediction models to refine PAD assessment. In this line, the usefulness of multimarker approaches to evaluate this complex multifactorial disease will be also discussed.  相似文献   
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23.
Extracellular vesicles (EV) are microparticles released in biological fluids by different cell types, both in physiological and pathological conditions. Owing to their ability to carry and transfer biomolecules, EV are mediators of cell-to-cell communication and are involved in the pathogenesis of several diseases. The ability of EV to modulate the immune system, the coagulation cascade, the angiogenetic process, and to drive endothelial dysfunction plays a crucial role in the pathophysiology of both autoimmune and renal diseases. Recent studies have demonstrated the involvement of EV in the control of renal homeostasis by acting as intercellular signaling molecules, mediators of inflammation and tissue regeneration. Moreover, circulating EV and urinary EV secreted by renal cells have been investigated as potential early biomarkers of renal injury. In the present review, we discuss the recent findings on the involvement of EV in autoimmunity and in renal intercellular communication. We focused on EV-mediated interaction between the immune system and the kidney in autoimmune diseases displaying common renal damage, such as antiphospholipid syndrome, systemic lupus erythematosus, thrombotic microangiopathy, and vasculitis. Although further studies are needed to extend our knowledge on EV in renal pathology, a deeper investigation of the impact of EV in kidney autoimmune diseases may also provide insight into renal biological processes. Furthermore, EV may represent promising biomarkers of renal diseases with potential future applications as diagnostic and therapeutic tools.  相似文献   
24.
Extracellular vesicles (EVs) are cell-derived nanostructures that mediate intercellular communication by delivering complex signals in normal tissues and cancer. The cellular coordination required for tumor development and maintenance is mediated, in part, through EV transport of molecular cargo to resident and distant cells. Most studies on EV-mediated signaling have been performed in two-dimensional (2D) monolayer cell cultures, largely because of their simplicity and high-throughput screening capacity. Three-dimensional (3D) cell cultures can be used to study cell-to-cell and cell-to-matrix interactions, enabling the study of EV-mediated cellular communication. 3D cultures may best model the role of EVs in formation of the tumor microenvironment (TME) and cancer cell-stromal interactions that sustain tumor growth. In this review, we discuss EV biology in 3D culture correlates of the TME. This includes EV communication between cell types of the TME, differences in EV biogenesis and signaling associated with differing scaffold choices and in scaffold-free 3D cultures and cultivation of the premetastatic niche. An understanding of EV biogenesis and signaling within a 3D TME will improve culture correlates of oncogenesis, enable molecular control of the TME and aid development of drug delivery tools based on EV-mediated signaling.  相似文献   
25.
Embryonic implantation is a key step in the establishment of pregnancy. In the present work, we have carried out an in-depth proteomic analysis of the secretome (extracellular vesicles and soluble proteins) of two bovine blastocysts embryonic trophectoderm primary cultures (BBT), confirming different epithelial–mesenchymal transition stages in these cells. BBT-secretomes contain early pregnancy-related proteins and angiogenic proteins both as cargo in EVs and the soluble fraction. We have demonstrated the functional transfer of protein-containing secretome between embryonic trophectoderm and maternal MSC in vitro using two BBT primary cultures eight endometrial MSC (eMSC) and five peripheral blood MSC (pbMSC) lines. We observed that eMSC and pbMSC chemotax to both the soluble fraction and EVs of the BBT secretome. In addition, in a complementary direction, we found that the pattern of expression of implantation proteins in BBT-EVs changes depending on: (i) their epithelial–mesenchymal phenotype; (ii) as a result of the uptake of eMSC- or pbMSC-EV previously stimulated or not with embryonic signals (IFN-τ); (iii) because of the stimulation with the endometrial cytokines present in the uterine fluid in the peri-implantation period.  相似文献   
26.
综述了阴/阳离子表面活性剂混合溶液在浓度比较高时出现的双水相和囊泡现象,并对这种双水相形成条件和囊泡的稳定性进行了比较详细的讨论。阴/阳离子表面活性剂混合溶液中的双水相现象只能在两个非常狭窄的区域形成,可能由不同浓度的胶束溶液、胶束溶液与液晶相或囊泡等组成。在一定的条件下,比较稳定的囊泡可以自发或经过超声处理形成。  相似文献   
27.
Supramolecular assemblies from chitosan-graft-β-cyclodextrin (CS-g-CD) and benzimidazole ended poly(ethylene glycol)-block-poly(ε-caprolactone) (PEG-b-PCL-BM) were formed based on the inclusion complexation between β-cyclodextrin and benzimidazole. The supra-amphiphiles self-assembled into complex vesicles with PCL/β-CD as the hydrophobic membrane, hydrophilic PEG and CS as the corona. The hydrophobic membrane and aqueous lumen of vesicles exhibited efficient entrapment both for hydrophobic curcumin (CUR) and hydrophilic doxorubicin (DOX). The drug loading of vesicles was more than 20.2% and 38.4% for CUR and DOX, respectively. Decreasing pH to acidic condition or increasing temperature, more controllable and rapid release of two drugs was observed. Cytotoxicity assays revealed that dual drug-loaded vesicles retained high cell proliferation inhibition efficiency than free drugs.GRAPHICAL ABSTRACT  相似文献   
28.
研究了异养菌和自养菌颗粒污泥的特性:与异养菌相比,自养菌颗粒污泥粒径小、密度大、胞外多聚物(EPS)含量高但强度小。通过对粒径、EPS等特性与密度的变化规律分析,研究发现,自养菌颗粒污泥的粒径与密实度呈现出一致性,颗粒趋于稳定;而异养菌颗粒污泥粒径成长同时伴随着密度减小,粒径与密实度呈现不一致性,颗粒容易解体。颗粒强度的分析结果表明:在自养菌系统中EPS与孔隙率能够达到动态平衡是其长期维持稳定的主要原因,而异养菌中粒径与孔隙率无法达到平衡,操作条件无法控制高强度丝状菌的繁殖是其不稳定的主要因素。  相似文献   
29.
水质条件对厌氧氨氧化颗粒污泥EPS含量的影响   总被引:5,自引:2,他引:3  
为研究水质条件对厌氧氨氧化颗粒污泥EPS含量的影响,采用16个SBR反应器研究同周期内基质利用阶段与基质匮乏阶段EPS含量的变化以及总氮质量浓度、IC/TN、COD/TN对于厌氧氨氧化颗粒污泥EPS含量的影响.结果表明,同周期内,基质利用阶段的EPS含量不断升高,基质匮乏阶段EPS含量不断降低;总氮质量浓度为35~280 mg/L时,提高总氮质量浓度可以提高EPS的含量,总氮质量浓度280 mg/L时EPS含量有所减少;IC/TN为0.01~0.2时,EPS及其各组分含量随无机碳质量浓度的升高而增加,IC/TN0.2时,无机碳质量浓度对于EPS及其各组分含量无明显影响;COD/TN0.5时,有机物对于EPS含量具有促进作用,COD/TN0.5时,有机物的提高对于EPS含量有抑制作用.在厌氧氨氧化颗粒污泥工艺的实际运行过程中,应避免过长的基质利用阶段与基质匮乏阶段,总氮质量浓度应保持在150~210 mg/L,无机碳质量浓度应保持在IC/TN为0.1~0.2,有机物质量浓度应保持在COD/TN0.5.  相似文献   
30.
不同活性污泥胞外聚合物提取方法优化   总被引:3,自引:0,他引:3  
活性污泥胞外聚合物( extracellular polymeric substances, EPS)是污水生物处理过程中污泥结构、脱水性能、絮凝性能以及沉降性能的重要决定因素,而提取方法不同EPS的剥离程度存在很大的差别.因此EPS提取方法的建立至关重要.采用6种方法提取不同污泥EPS,分析了不同污泥每g干污泥中分层EPS的质量及组成,并考察了污泥粒径及脱水性能与污泥EPS的关系.结果表明:不同工艺不同污泥每g干污泥中EPS质量不同;甲醛+NaOH法提取EPS效率高且对细胞破坏程度小,试验中不同污泥EPS提取量为15.88~39.30 mg;每g干污泥中黏液层EPS质量越高,蛋白质与多糖质量浓度之比越大,污泥脱水性能越差;污泥EPS的提取效率与污泥粒径存在一定的相关性,污泥粒径越大,提取效率越高.  相似文献   
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