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21.
Martina Mazzariol Giovanni Camussi Maria Felice Brizzi 《International journal of molecular sciences》2021,22(8)
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
22.
The vinyl ester-type glycomonomer 6-O-vinyladipoyl-d-glucopyranose was polymerized in water and alcohol solutions. In all cases, long polymerization times were necessary to achieve reasonable conversions. Depending on the nature of the solvent, polydisperse glycopolymers were obtained possessing a molecular weight ranging between 10,000 and 122,000 Da (PS equivalent). Higher alcohols appeared to act as chain transfer agents and oligomers with DPn between 2 and 6 were indeed obtained when 2-propanol was the solvent. Also, thorough oxygen removal from the reaction mixture proved to be essential for the success of the experiment, plain nitrogen sparging being ineffective in most cases. 相似文献
23.
Extreme-scale computing is set to provide the infrastructure for the advances and breakthroughs that will solve some of the hardest problems in science and engineering. However, resilience and energy concerns loom as two of the major challenges for machines at that scale. The number of components that will be assembled in the supercomputers plays a fundamental role in these challenges. First, a large number of parts will substantially increase the failure rate of the system compared to the failure frequency of current machines. Second, those components have to fit within the power envelope of the installation and keep the energy consumption within operational margins. Extreme-scale machines will have to incorporate fault tolerance mechanisms and honor the energy and power restrictions. Therefore, it is essential to understand how fault tolerance and energy consumption interplay. This paper presents a comparative evaluation and analysis of energy consumption of three different rollback-recovery protocols: checkpoint/restart, message logging and parallel recovery. Our experimental evaluation shows parallel recovery has the minimum execution time and energy consumption. Additionally, we present an analytical model that projects parallel recovery can reduce energy consumption more than 37% compared to checkpoint/restart at extreme scale. 相似文献
24.
Jhon Harley Muñoz Romero Cindy Alejandra Sepúlveda Cadavid Natalie Cortés Julián Esteban López Correa 《臭氧:科学与工程》2020,42(1):36-42
ABSTRACTIn this study, the efficiency of gaseous ozone (O3) injected in the soil as an oxidizing agent for the inactivation of F. oxysporum was evaluated under laboratory conditions. The results show the treatment reached an inactivation efficiency of 76% after an applied dose of 0.40 g O3 kg ?1 soil. This shows that the injection of O3 can be a viable alternative to control pathogenic organisms in the soils. Nevertheless, it is clear that more studies on determining the effects of this treatment on soil quality are needed. 相似文献
25.
E. E. Vicente S. Bermúdez A. Esteban R. Tendler B. Arcondo H. Sirkin 《Journal of Materials Science》1991,26(5):1327-1332
Invariant three- and four-phase equilibria in the magnesium-rich corner of the Mg-Cu-Sn ternary system have been studied by differential thermal analysis, optical microscopy, electron probe microanalysis and X-ray diffraction. The L(Mg) + Mg2 Cu + Mg2Sn ternary eutectic reaction was found to be at 467 °C and at Mg–13.5 at % Cu–4.4 at% Sn. The LMg2Cu + Mg2Sn pseudo-binary eutectic reaction is tentatively located at 522°C and at Mg–26.0 at % Cu–7.7 at % Sn. 相似文献
26.
27.
Huy Minh Dao Amit Raviraj Pillai Rishi Thakkar Sanjiv Parajuli Esteban Urena-Benavides Seongbong Jo 《应用聚合物科学杂志》2021,138(2):49665
Light-sensitive drug delivery systems are considered ideal for applications in the biomedical fields for their ability to release the payload in an on-demand spatiotemporal controlled manner through the manipulation of the light source. Among the broad radiation spectrum, near infrared (NIR) light is considered advantageous compared to UV and visible light, due to its inherently lower photodamage to normal tissues and deeper penetration to lesion areas. In this study, we report a successful synthesis of a polymer capable of undergoing partial degradation upon irradiation with NIR light by conjugating 10-N-carbamoyl linkage methylene blue (MB) moiety, a NIR photocleavable ligand, with polyethylene glycol (PEG). Through effective coupling of MB, a hydrophobic moiety, to the hydrophilic PEG molecule, an amphiphilic polymer was synthesized, as demonstrated by a lowered surface tension (55 mN/m at 0.1% wt/vol). Subsequently, photo-induced reversal of surface activity associated with self-assembled structure disruption, was displayed by surface tension measurements, size distribution analysis, and burst release profile of paclitaxel (PTX) from polymeric micelles upon the exposure to NIR irradiation. 相似文献
28.
Miguel Gallardo-Cervantes Yolanda González-García Aida Alejandra Pérez-Fonseca Martín Esteban González-López Ricardo Manríquez-González Denis Rodrigue Jorge Ramón Robledo-Ortíz 《应用聚合物科学杂志》2021,138(15):50182
In this work, biocomposites made of polyhydroxyalkanoates (PHA) with natural fibers were produced via compression molding. In particular, polyhydroxybutyrate (PHB) and polyhydroxybutyrate-co-hydroxyvalerate (PHBV) were reinforced with 20 wt% of agave fibers. Different compatibilization strategies were investigated to improve the fiber-matrix interaction: fiber surface treatment in PHA solution, fiber surface treatment in maleated PHA solution, fiber propionylation, and extrusion with maleated PHA. The biocomposites were characterized in terms of morphology, mechanical properties, water absorption, and biodegradability by CO2 production tracking. In general, fiber propionylation was the best strategy for mechanical properties enhancement and water uptake decreasing. Biocomposites with propionylated fibers showed improved flexural strength (170% for PHB and 84% for PHBV). The flexural modulus was also enhanced with propionylated fibers up to 19% and 18% compared to uncompatibilized biocomposites (PHB and PHBV, respectively). Tensile strength increased by 16% (PHB) and 14% (PHBV), and the water absorption was reduced using propionylated fibers going from 6.6% to 4.4% compared with biocomposites with untreated fibers. Most importantly, the impact strength was also improved for all biocomposites by up to 96% compared with the neat PHA matrices. Finally, it was found that the compatibilization did not negatively modify the PHA biodegradability. 相似文献
29.
Esteban J. Palomo Enrique Domínguez Rafael M. Luque-Baena José Muñoz 《Neural Processing Letters》2013,37(1):69-87
Both image compression based on color quantization and image segmentation are two typical tasks in the field of image processing. Several techniques based on splitting algorithms or cluster analyses have been proposed in the literature. Self-organizing maps have been also applied to these problems, although with some limitations due to the fixed network architecture and the lack of representation in hierarchical relations among data. In this paper, both problems are addressed using growing hierarchical self-organizing models. An advantage of these models is due to the hierarchical architecture, which is more flexible in the adaptation process to input data, reflecting inherent hierarchical relations among data. Comparative results are provided for image compression and image segmentation. Experimental results show that the proposed approach is promising for image processing, and the powerful of the hierarchical information provided by the proposed model. 相似文献
30.
C. Melody Carswell Cindy H. Lio Martina I. Klein Duncan Clarke Stephen Strup 《Applied ergonomics》2010,42(1):138-145