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1.
David Diaz Elisa Lopez-Dolado Sergio Haro Jorge Monserrat Carlos Martinez-Alonso Dimitrios Balomeros Agustín Albillos Melchor Alvarez-Mon 《International journal of molecular sciences》2021,22(2)
Our aim was to investigate the subset distribution and function of circulating monocytes, proinflammatory cytokine levels, gut barrier damage, and bacterial translocation in chronic spinal cord injury (SCI) patients. Thus, 56 SCI patients and 28 healthy donors were studied. The levels of circulating CD14+highCD16−, CD14+highCD16+, and CD14+lowCD16+ monocytes, membrane TLR2, TLR4, and TLR9, phagocytic activity, ROS generation, and intracytoplasmic TNF-α, IL-1, IL-6, and IL-10 after lipopolysaccharide (LPS) stimulation were analyzed by polychromatic flow cytometry. Serum TNF-α, IL-1, IL-6 and IL-10 levels were measured by Luminex and LPS-binding protein (LBP), intestinal fatty acid-binding protein (I-FABP) and zonulin by ELISA. SCI patients had normal monocyte counts and subset distribution. CD14+highCD16− and CD14+highCD16+ monocytes exhibited decreased TLR4, normal TLR2 and increased TLR9 expression. CD14+highCD16− monocytes had increased LPS-induced TNF-α but normal IL-1, IL-6, and IL-10 production. Monocytes exhibited defective phagocytosis but normal ROS production. Patients had enhanced serum TNF-α and IL-6 levels, normal IL-1 and IL-10 levels, and increased circulating LBP, I-FABP, and zonulin levels. Chronic SCI patients displayed impaired circulating monocyte function. These patients exhibited a systemic proinflammatory state characterized by enhanced serum TNF-α and IL-6 levels. These patients also had increased bacterial translocation and gut barrier damage. 相似文献
2.
Lihua Lou Weijie Yu Ronald J. Kendall Ernest Smith Seshadri S. Ramkumar 《应用聚合物科学杂志》2020,137(30):49213
A tensile properties testing study was conducted to understand the influence of thickness, cross-head speed (speed of testing), gauge length (GL; specimen test length), and sample shape on important tensile properties of polyvinyl alcohol (PVA) nanofiber webs. The effects of each testing parameter on load at break, extension at break, Young's modulus, and tensile stress–strain curve of PVA nanofiber webs are analyzed. The Welch two sample t-tests show the significant difference among tested data. Using interaction plots, two-way analysis of variance, and margin mean plots, the interaction effects among testing parameters have been analyzed. Of all the factors, cross-head speed, the interaction among GL, and sample thickness (GL: Thickness) and the interaction among GL, testing speed and sample thickness (GL: Speed: Thickness) have significant influence on the tensile properties of PVA nanofiber webs. Moreover, the hypothesized model of mechanism of tensile strain–stress curve of PVA nanofiber webs has been proposed. Based on the model, the tensile strain–stress curve can be split into three stages: linear elastic, partial break up, and complete breakage. This study will provide a better understanding of tensile testing parameters' effects and their interaction effects on the tensile properties of nanowebs. 相似文献
3.
Daniela Frasca Maria Romero Alain Diaz Denisse Garcia Seth Thaller Bonnie B. Blomberg 《International journal of molecular sciences》2021,22(4)
Senescent cells accumulate in the adipose tissue (AT) of individuals with obesity and secrete multiple factors that constitute the senescence-associated secretory phenotype (SASP). This paper aimed at the identification of B cells with a SASP phenotype in the AT, as compared to the peripheral blood, of individuals with obesity. Our results show increased expression of SASP markers in AT versus blood B cells, a phenotype associated with a hyper-metabolic profile necessary to support the increased immune activation of AT-derived B cells as compared to blood-derived B cells. This hyper-metabolic profile is needed for the secretion of the pro-inflammatory mediators (cytokines, chemokines, micro-RNAs) that fuel local and systemic inflammation. 相似文献
4.
Joo H. Kang Eujin Um Alexander Diaz Harry Driscoll Melissa J. Rodas Karel Domansky Alexander L. Watters Michael Super Howard A. Stone Donald E. Ingber 《Small (Weinheim an der Bergstrasse, Germany)》2015,11(42):5657-5666
Magnetic nanoparticles have been employed to capture pathogens for many biological applications; however, optimal particle sizes have been determined empirically in specific capturing protocols. Here, a theoretical model that simulates capture of bacteria is described and used to calculate bacterial collision frequencies and magnetophoretic properties for a range of particle sizes. The model predicts that particles with a diameter of 460 nm should produce optimal separation of bacteria in buffer flowing at 1 L h−1. Validating the predictive power of the model, Staphylococcus aureus is separated from buffer and blood flowing through magnetic capture devices using six different sizes of magnetic particles. Experimental magnetic separation in buffer conditions confirms that particles with a diameter closest to the predicted optimal particle size provide the most effective capture. Modeling the capturing process in plasma and blood by introducing empirical constants (ce), which integrate the interfering effects of biological components on the binding kinetics of magnetic beads to bacteria, smaller beads with 50 nm diameters are predicted that exhibit maximum magnetic separation of bacteria from blood and experimentally validated this trend. The predictive power of the model suggests its utility for the future design of magnetic separation for diagnostic and therapeutic applications. 相似文献
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Chris Gibbons Corrine Chaves Ronald B. Wilkes Mark N. Frolick 《Information Systems Management》1994,11(3):51-56
Information-based organizations are structured to function with as small and efficient a staff as possible. To this end, executives at The Promus Companies are using IT to spread decision-making authority and responsibility for customer satisfaction and customer service throughout the organization. 相似文献
8.
Ahn Jaeshin Stromsmoe Keith A. Lawson Ronald P. W. 《Industrial Electronics, IEEE Transactions on》1985,(4):405-409
A microprocessor-based system with 32 A/D, 24 D/A, and 16 ac load controllers, has been designed and built to monitor and control an ion beam thin-film deposition system. The A/D and D/A channels have electrical isolation of 7.5 kV between channels and between input and output. The microprocessor system keeps the ion beam deposition parameters stable for extended periods of operation and it is proposed as a means to greatly simplify switching from one deposition species to another to grow thin multilayer or alloy films. 相似文献
9.
A new and simple method of finite-element grid improvement is presented. The objective is to improve the accuracy of the analysis. The procedure is based on a minimization of the trace of the stiffness matrix. For a broad class of problems this minimization is seen to be equivalent to minimizing the potential energy. The method is illustrated with the classical tapered bar problem examined earlier by Prager and Masur. Identical results are obtained. 相似文献
10.
Hypothesized, on the basis of findings from several studies, that rejected children are more disruptive, aggressive, and socially inappropriate than are their classmates. Three groups of 39 rejected, 29 neglected, and 39 accepted children were randomly selected from 282 boys and 210 girls who were identified separately on the basis of sociometric scores for 492 children in Grades 3–6. The 3 groups were compared using multiple analysis of variance (MANOVA) on measures from 4 domains: peer behavioral attributions, teacher ratings, analog assertiveness task, and self-evaluation. Rejected Ss were clearly distinguished from their same-sex neglected and accepted classmates and were described by teachers and peers as aggressive, disruptive and inattentive. Neglected Ss were only marginally discriminable from same-sex accepted children. Neither neglected nor rejected Ss were differentiated from accepted Ss with respect to observed assertiveness and self-ratings of shyness, unhappiness, and feeling unaccepted. The results replicate previous findings for rejected children. Currently, there is not sufficient justification to consider the group of socially neglected children as a clinical category. (21 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献