miR-126 promotes angiogenesis and attenuates inflammation after contusion spinal cord injury in rats

AbstractMicroRNAs are a class of small RNAs that regulate the expression of target mRNAs by inhibiting translation or destabilizing target mRNAs. miR-126 is a microRNA that is highly enriched in endothelial cells. miR-126 has been found to promote angiogenesis and inhibit vascular inflammation in endothelial cells by repressing three target genes Sprouty-related EVH1 domain-containing protein 1 (SPRED1), phosphoinositol-3 kinase regulatory subunit 2 (PIK3R2), and vascular cell adhesion molecule 1 (VCAM1). Our previous study showed that the expression of miR-126 was downregulated after spinal cord injury (SCI). Therefore, we wanted to examine whether upregulation of miR-126 could promote angiogenesis, inhibit inflammation, and exert a positive effect on recovery after contusion SCI. In this study, we found that increased levels of miR-126 promoted angiogenesis, and inhibited leukocyte extravasation into the injured spinal cord, which was concurrent with downregulation of mRNA and protein expression of three validated miR-126 target genes, SPRED1, PIK3R2, and VCAM1. Moreover, a dose-dependent effect of miR-126 was observed in rescuing tissue damage and improving the functional deficit after SCI. Thus, the present study indicated that miR-126 played an important role in angiogenesis and inflammation after SCI

Restoration of soil quality of degraded grassland can be accelerated by reseeding in an arid area of Northwest China

Grassland restoration measures control soil degradation and improve soil quality (SQ) worldwide, but there is little knowledge about the effectiveness of restoration measures affecting SQ in arid areas, and the restoration rate of degraded grasslands to natural restoration grasslands and reseeded grasslands remains unclear. To establish a soil quality index (SQI) to evaluate the effects of different grassland restoration measures on SQ, continuous grazing grassland (CG) (as a reference), grazing exclusion grassland (EX), and reseeding grassland (RS) were selected and sampled in the arid desert steppe. Two soil indicator selection methods were conducted (total data set (TDS) and minimum data set (MDS)), followed by three SQ indices (additive soil quality index (SQIa), weighted additive soil quality index (SQIw), and Nemoro soil quality index (SQIn)). The results indicated that SQ was better assessed using the SQIw (R2 = 0.55) compared to SQIa and SQIn for indication differences among the treatments due to the larger coefficient of variance. The SQIw-MDS value in CG grassland was 46% and 68% lower than that of EX grassland and RS grassland, respectively. Our findings provided evidence that restoration practices of grazing exclusion and reseeding can significantly improve the SQ in the arid desert steppe, and native plant reseeded can accelerate soil quality restoration

A Novel Graphene Quantum Dot-Based mRNA Delivery Platform

During the last decades, there has been growing interest in using therapeutic messager RNA (mRNA) together with drug delivery systems. Naked, unformulated mRNA is, however, unable to cross the cell membrane and is susceptible to degradation. Here we use graphene quantum dots (GQDs) functionalized with polyethyleneimine (PEI) as a novel mRNA delivery system. Our results show that these modified GQDs can be used to deliver intact and functional mRNA to Huh-7 hepatocarcinoma cells at low doses and, that the GQDs are not toxic, although cellular toxicity is a problem for these first-generation modified particles. Functionalized GQDs represent a potentially interesting delivery system that is easy to manufacture, stable and effective

Control of sunroof buffeting noise by optimizing the flow field characteristics of a commercial vehicle

When a commercial vehicle is driving with the sunroof open, it is easy for the problem of sunroof buffeting noise to occur. This paper establishes the basis for the design of a commercial vehicle model that solves the problem of sunroof buffeting noise, which is based on computational fluid dynamics (CFD) numerical simulation technology. The large eddy simulation (LES) method was used to analyze the characteristics of the buffeting noise with different speed conditions while the sunroof was open. The simulation results showed that the small vortex generated in the cab forehead merges into a large vortex during the backward movement, and the turbulent vortex causes a resonance response in the cab cavity as the turbulent vortex moves above the sunroof and falls into the cab. Improving the flow field characteristics above the cab can reduce the sunroof buffeting noise. Focusing on the buffeting noise of commercial vehicles, it is proposed that the existing accessories, including sun visors and roof domes, are optimized to deal with the problem of sunroof buffeting noise. The sound pressure level of the sunroof buffeting noise was reduced by 6.7 dB after optimization. At the same time, the local pressure drag of the commercial vehicle was reduced, and the wind resistance coefficient was reduced by 1.55% compared to the original commercial vehicle. These results can be considered as relevant, with high potential applicability, within this field of researchThis work was supported by the National Natural Science Foundation of China (No. 52065013), the Guangxi Youth Science Fund Project (2018GXNSFBA281012), the Innovation-Driven Development Special Fund Project of Guangxi (Guike AA19182004), and the Liuzhou Scientific Research and Planning Development Project (2018AA20301)S

Effects of Tert-Butylhydroquinone on Intestinal Inflammatory Response and Apoptosis following Traumatic Brain Injury in Mice

Traumatic brain injury (TBI) can induce intestinal inflammatory response and mucosal injury. Antioxidant transcription factor nuclear factor erythroid 2-related factor 2 (Nrf2) has been shown in our previous studies to prevent oxidative stress and inflammatory response in gut after TBI. The objective of this study was to test whether tert-butylhydroquinone (tBHQ), an Nrf2 inducer, can protect against TBI-induced intestinal inflammatory response and mucosal injury in mice. Adult male ICR mice were randomly divided into three groups: (1) sham + vehicle group, (2) TBI + vehicle group, and (3) TBI + tBHQ group (n = 12 per group). Closed head injury was adopted using Hall's weight-dropping method. Intestinal mucosa apoptosis and inflammatory-related factors, such as nuclear factor kappa B (NF-κB), tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), interleukin-6 (IL-6) and intercellular adhesion molecule-1 (ICAM-1), were investigated at 24 h after TBI. As a result, we found that oral treatment with 1% tBHQ prior to TBI for one week markedly decreased NF-κB activation, inflammatory cytokines production, and ICAM-1 expression in the gut. Administration of tBHQ also significantly attenuated TBI-induced intestinal mucosal apoptosis. The results of the present study suggest that tBHQ administration could suppress the intestinal inflammation and reduce the mucosal damage following TBI

The Manufacture and Mechanical Analysis of the PVDF Flexible Sensors

Polyvinylidene fluoride (PVDF) is a widely used sensing material with piezoelectricity property. Applying microelectronic technology to this material could result in multifunctional sensing unit. Based on the previous researches, a manufacturing process and flexible structure are proposed to manufacture the PVDF film and the PVDF flexible sensor using stretchable electronic technology. The sensor is designed to be paved on the surface of airfoil to monitor the structural behaviors. Two systems are compared, one with a polydimethylsiloxane (PDMS) layer and the other without. The finite element results show that the Au electrodes films are harder to be destructed for the system with PDMS, because the PVDF flexible sensor can realize the strain-isolation, therefore the resistance to destruction of the sensors could be improved. However, the deformation of duralumin is increased, so the substrate that the flexible sensor paves on will undertake a majority portion of stresses and strains, and a substrate with reasonable stiffness will contribute to the structure integrity