375 research outputs found
Semilocal Convergence for a Fifth-Order Newton's Method Using Recurrence Relations in Banach Spaces
We study a modified Newton's method with fifth-order convergence for nonlinear equations in Banach spaces. We make an attempt to establish the semilocal convergence of this method by using recurrence relations.
The recurrence relations for the method are derived, and then an existence-uniqueness theorem is given to establish the
R-order of the method to be five and a priori error bounds. Finally, a numerical application is presented to demonstrate
our approach
A Collection-Distribution Center Location and Allocation Optimization Model in Closed-Loop Supply Chain for Chinese Beer Industry
Recycling waste products is an environmental-friendly activity that can result in manufacturing cost saving and economic efficiency improving. In the beer industry, recycling bottles can reduce manufacturing cost and the industry’s carbon footprint. This paper presents a model for a collection-distribution center location and allocation problem in a closed-loop supply chain for the beer industry under a fuzzy random environment, in which the objectives are to minimize total costs and transportation pollution. Both random and fuzzy uncertainties, for which return rate and disposal rate are considered fuzzy random variables, are jointly handled in this paper to ensure a more practical problem solution. A heuristic algorithm based on priority-based global-local-neighbor particle swarm optimization (pb-glnPSO) is applied to ensure reliable solutions for this NP-hard problem. A beer company case study is given to illustrate the application of the proposed model and to demonstrate the priority-based global-local-neighbor particle swarm optimization
Moderate Exercise Enhances Endothelial Progenitor Cell Exosomes Release and Function
Purpose: Exercise has cardiovascular benefits which might be related to endothelial progenitor cells (EPC). Meanwhile, there is evidence suggesting that EPC-derived exosomes (EPC-EX) promote vascular repair and angiogenesis through their carried microRNA (miR)-126. In this study, we investigated whether exercise could increase the levels of circulating EPC-EX and their miR-126 cargo, and by which promote the protective function of EPC-EX on endothelial cells (EC). Methods: Plasma EPC-EX from sedentary, low, or moderate exercise mice, respectively, denoted as EPC-EXS, EPC-EXL, and EPC-EXM, were isolated using microbead-based sorting techniques and characterized by nanoparticle tracking analysis, Western blot, and quantitative real-time polymerase chain reaction assessments of biomarkers and miR-126. High glucose (25 mM) with hypoxia (1% O2) was used for inducing an EC injury model. The injured EC were treated by coculturing with vehicle, EPC-EXS, EPC-EXL, EPC-EXM, or EPC-EXM + anti–miR-126. After that, EC were used for flow cytometry analysis of apoptosis, assessments of tube formation and migration, and measurements of miR-126 level and its downstream sprouty-related protein-1 (SPRED1) and vascular endothelial growth factor (VEGF). Results: 1) Isolated EPC-EX positively expressed exosomal markers (CD63 and Tsg101) and EPC markers (CD34 and VEGFR2). 2) Exercise intensity dependently elevated plasma level of EPC, EPC-EX/EPC ratio, and miR-126 expression in EPC and EPC-EX. 3) Injured EC displayed apoptosis increment, angiogenic dysfunction and miR-126 reduction. 4) EPC-EXM had better effects than EPC-EXS and EPC-EXL on alleviating those changes of injured EC, accompanied with SPRED1 downregulation and VEGF upregulation. 5) The effects of EPC-EXM were abolished by miR-126 knockdown. Conclusions: Our data demonstrate that exercise can increase EPC-EX release and miR-126 level and enhance the effects of EPC-EX on protecting EC against injury through the SPRED1/VEGF pathway
Association of autoantibodies against the M2-muscarinic receptor with perinatal outcomes in women with severe preeclampsia
Microvascular Endothelial Cells-Derived Microvesicles Imply in Ischemic Stroke by Modulating Astrocyte and Blood Brain Barrier Function and Cerebral Blood Flow
Background Endothelial cell (EC) released microvesicles (EMVs) can affect various target cells by transferring carried genetic information. Astrocytes are the main components of the blood brain barrier (BBB) structure in the brain and participate in regulating BBB integrity and blood flow. The interactions between ECs and astrocytes are essential for BBB integrity in homeostasis and pathological conditions. Here, we studied the effects of human brain microvascular ECs released EMVs on astrocyte functions. Additionally, we investigated the effects of EMVs treated astrocytes on regulating BBB function and cerebral ischemic damage. Results EMVs prepared from ECs cultured in normal condition (n-EMVs) or oxygen and glucose deprivation (OGD-EMVs) condition had diverse effects on astrocytes. The n-EMVs promoted, while the OGD-EMVs inhibited the proliferation of astrocytes via regulating PI3K/Akt pathway. Glial fibrillary acidic protein (GFAP) expression (marker of astrocyte activation) was up-regulated by n-EMVs, while down-regulated by OGD-EMVs. Meanwhile, n-EMVs inhibited but OGD-EMVs promoted the apoptosis of astrocytes accompanied by up/down-regulating the expression of Caspase-9 and Bcl-2. In the BBB model of ECs-astrocytes co-culture, the n-EMVs, conversely to OGD-EMVs, decreased the permeability of BBB accompanied with up-regulation of zonula occudens-1(ZO-1) and Claudin-5. In a transient cerebral ischemia mouse model, n-EMVs ameliorated, while OGD-EMVs aggravated, BBB disruption, local cerebral blood flow (CBF) reduction, infarct volume and neurological deficit score. Conclusions Our data suggest that EMVs diversely modulate astrocyte functions, BBB integrity and CBF, and could serve as a novel therapeutic target for ischemic stroke
Phenotypic and genotypic characterization of Human Immunodeficiency Virus type 1 CRF07_BC strains circulating in the Xinjiang Province of China
BACKGROUND: HIV-1 CRF07_BC recombinant previously circulated mainly among the intravenous drug users (IDUs) in Xinjiang province of China and is currently spreading in the entire country. The aim of this study is to characterize the genotypic and phenotypic properties of HIV-1 CRF07_BC isolates in comparison with those of the subtype B' (Thailand B) which is prevalent in the former plasma donors (FPDs) in China. RESULTS: Twelve HIV-1 CRF07_BC variants were isolated from the blood of the HIV-1-infected IDUs in Xinjiang province, and 20 subtype B' isolates were obtained from the FPDs in Anhui and Shanxi provinces of China. All the CRF07_BC viruses utilized CCR5 co-receptor, whereas 12 subtype B' viruses were R5-tropic, and the remaining B' isolates were dual (R5X4) tropic. CRF07_BC viruses had lower net charge value in the V3 loop and exhibited slower replication kinetics than subtype B' viruses. The number and location of the potential N-linked glycosylation sites in V1/V2 and the C2 region of the CRF07_BC viruses were significantly different from those of the subtype B' viruses. CONCLUSION: The HIV-1 CRF07_BC recombinant strains with relatively lower net charges in the V3 loop exclusively utilize CCR5 co-receptor for infection and exhibit slow replication kinetics in the primary target cells, suggesting that CRF07_BC may be superior over B' and other HIV-1 subtypes in initiating infection in high-risk population. These findings have molecular implications for the adaptive evolution of HIV-1 circulating in China and the design of tailored therapeutic strategy for treatment of HIV-1 CRF07_BC infection
miR-132-3p Priming Enhances the Effects of Mesenchymal Stromal Cell-Derived Exosomes on Ameliorating Brain Ischemic Injury
Backgrounds/aims: Mesenchymal stromal cell-derived exosomes (MSC-EXs) could exert protective effects on recipient cells by transferring the contained microRNAs (miRs), and miR-132-3p is one of angiogenic miRs. However, whether the combination of MSC-EXs and miR-132-3p has better effects in ischemic cerebrovascular disease remains unknown. Methods: Mouse MSCs transfected with scrambler control or miR-132-3p mimics were used to generate MSC-EXs and miR-132-3p-overexpressed MSC-EXs (MSC-EXsmiR-132-3p). The effects of EXs on hypoxia/reoxygenation (H/R)-injured ECs in ROS generation, apoptosis, and barrier function were analyzed. The levels of RASA1, Ras, phosphorylations of PI3K, Akt and endothelial nitric oxide synthesis (eNOS), and tight junction proteins (Claudin-5 and ZO-1) were measured. Ras and PI3K inhibitors were used for pathway analysis. In transient middle cerebral artery occlusion (tMCAO) mouse model, the effects of MSC-EXs on the cerebral vascular ROS production and apoptosis, cerebral vascular density (cMVD), Evans blue extravasation, brain water content, neurological deficit score (NDS), and infarct volume were determined. Results: MSC-EXs could deliver their carried miR-132-3p into target ECs, which functionally downregulated the target protein RASA1, while upregulated the expression of Ras and the downstream PI3K phosphorylation. Compared to MSC-EXs, MSC-EXsmiR-132-3p were more effective in decreasing ROS production, apoptosis, and tight junction disruption in H/R-injured ECs. These effects were associated with increased levels of phosphorylated Akt and eNOS, which could be abolished by PI3K inhibitor (LY294002) or Ras inhibitor (NSC 23766). In the tMCAO mouse model, the infusion of MSC-EXsmiR-132-3p was more effective than MSC-EXs in reducing cerebral vascular ROS production, BBB dysfunction, and brain injury. Conclusion: Our results suggest that miR-132-3p promotes the beneficial effects of MSC-EXs on brain ischemic injury through protecting cerebral EC functions
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