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Whether long noncoding RNAs participate in the formation of abdominal aortic aneurysms (AAAs) through the regulation of SMC phenotypic switching is unknown. lincRNA-p21 induced by reactive oxygen species (ROS) is likely functionally associated with SMC phenotypic switching. We thus investigated the role of lincRNA-p21 in SMC phenotypic switching-associated AAA formation and its underlying mechanisms. An analysis of human and mouse abdominal aortic samples revealed that the lincRNA-p21 levels were significantly higher in AAA tissue. Stimulation with hydrogen peroxide upregulated the expression of lincRNA-p21 in a dose-dependent manner and converted SMCs from a contractile phenotype to a synthetic, proteolytic, and proinflammatory phenotype in vitro. Moreover, lincRNA-p21 promoted fracture of elastic fibres, reconstruction of the vascular wall, and AAA formation in vivo by modulating SMC phenotypic switching in two mouse models of AAA induced by angiotensin II or porcine pancreatic elastase (PPE) perfusion. Using a bioinformatics prediction method and luciferase reporter gene assays, we further proved that lincRNA-p21 sponged miR-204-5p to release the transcriptional activity of Mekk3 and promoted the NF-κB pathway and thereby played a role in the SMC phenotypic switch and AAA formation. The ROS levels were positively correlated with the lincRNA-p21 levels in human and mouse AAA tissues. The knockdown of lincRNA-p21 in a PPE-induced mouse AAA model increased the miR-204-5p levels and reduced the expression of Mekk3, whereas lincRNA-p21 overexpression had the opposite effect. Collectively, the results indicated that ROS-induced lincRNA-p21 sponges miR-204-5p to accelerate synthetic and proinflammatory SMC phenotypes through the Mekk3/NF-κB pathway in AAA formation. Thus, lincRNA-p21 may have therapeutic potential for AAA formation.

Low costs (material, energy and time), high joint properties are the eternal pursuit of modern welding. In this paper, mechanisms of an innovative high frequency electric cooperated arc welding (HFAW) in enhancing welding productivity (joint penetration) and weld property control were comprehensively investigated. The process properties and weld mechanisms of this method were systematically compared with that of the traditional GMAW welding under typical process parameters. The results showed that 4.8 mm joint with an large aspect ratio of 4 was achieved by single pass HFAW at a high welding speed (15 mm/s) and a low welding heat input (reduced 1/3 than the traditional GMAW). The research on weld property control shows that the microstructure of weld zone and heat affected zone (HAZ) in the HFAW joint was much smaller than that in the GMAW joint under optimal parameters. The width of each zone in the HAZ, thermal cycle parameters such as elevated temperature holding time and cooling rate can be regulated independently by the high frequency electric heat input ratio. Such regulation is of great significance for high strength steel welding, which needs to control the welding thermal cycle process accurately. Combined with three-dimensional solid reconstruction of liquid filler metal, the mechanism of the HFAW in enhancing joint penetration was demonstrated. An interesting “self-tracking heating” of the high frequency current was found. The cutting-edge of the liquid metal was violently heated and more than half of the weld in thickness direction was achieved by a novel ultra-speed “interfacial tension driving penetrating” weld forming mechanism, which promises the HFAW high welding speed and large aspect ratio on the premise of satisfactory welding quality.

Abdominal aortic aneurysm (AAA) is accepted as a chronic vascular inflammatory disease. However, how the inflammatory response is regulated during AAA formation is not fully understood. This study was undertaken to determine whether the long noncoding RNA (lncRNA) H19 (H19) promotes AAA formation by enhancing aortic inflammation. qRT-PCR detected the upregulation of H19 in human and mouse AAA tissue samples. Co-staining for H19 and the macrophage marker MAC-2 showed that H19 was located in vascular smooth muscle cells (VSMCs) and infiltrating aortic macrophages. In vivo overexpression of H19 increased vascular inflammation and induced AAA formation, which was supported by exacerbated aortic morphology, maximum aortic diameter values, elastin degradation, expression of interleukin-6 (IL-6) and macrophage chemoattractant protein-1 (MCP-1), and macrophage infiltration. H19 suppression resulted in the opposite effects. A rescue experiment indicated that IL-6 neutralization significantly mitigated the aortic inflammation and AAA formation evoked by H19 overexpression. Luciferase reporter assays and ex vivo experiments using VSMCs and macrophages confirmed that H19 induced aneurysm formation in part via endogenous competition with the let-7a microRNA to induce the transcription of its target gene, IL-6. This mechanism was further validated by in vivo experiments using a mutant H19 that could not effectively bind let-7a. Collectively, our study revealed a pathogenic H19/let-7a/IL-6 inflammatory pathway in AAA formation, which offers a new potential therapeutic strategy for AAA.

An efficient and rapid method for quantifying pyrethroids pesticide residue in fruits samples was developed in the present study. The application of lab prepared polystyrene magnetic nanoparticles based magnetic solid phase extraction technique combined with liquid-solid extraction helped clean-up the sample and preconcentrate the targeted analytes prior to HPLC quantification. The lab prepared nanoparticles were characterised with Fourier transform infrared spectroscopy, atomic force microscopy, X-ray diffraction spectroscopy, as well as vibrating sample magnetometer to study their size, morphology, crystal structure, functional groups and magnetism properties, respectively. Afterwards, optimisation of the parameters affecting extraction efficiency was carried out in order to achieve optimum conditions for extracting pyrethroids residue from fruit samples. Analytical performances were evaluated by carrying out experiments at optimum conditions. Results showed that the limit of detection and limit of quantification were below 0.1445 and 0.5116 ng g−1, respectively for the six pyrethroids tested. The recovery rates were within the range of 73.6%–123.1% with intra-day and inter-day relative standard deviation being less than 16.5% and 15.4%, respectively, suggesting satisfactory reproducibility of the proposed method. Real sample analysis was performed using 6 kinds of commonly consumed fruits obtained from local supermarkets in Singapore, including apples, pears, oranges, lemons, grapes and nectarines. The peel and flesh were tested separately to study the difference of pyrethroids residue in different parts of fruits. The grape sample tested was detected with permethrin residue on its peel. There was no violation since the permethrin amount detected was way much lower than the maximum residue limit set by local government.

3 mm thick Al-steel dissimilar metals were butt welded by a newly developed high frequency electric cooperated arc welding-brazing (HFAW-B) without grooves or shaping board. Microstructure characteristics and mechanical property of the joint were investigated and compared with that of the traditional single MIG joint. Results showed that sound joint with satisfactory weld appearance was achieved by the HFAW-B process under a low welding heat input (826 J/cm), while much higher heat input (1036 J/cm) was required for the traditional MIG process. The interfacial IMCs layer of the HFAW-B joint was homogeneous and thin (limited to 4.0 μm). In the traditional MIG joint, even with the same heat input, the maximum thickness of the IMCs layer exceeded 5.0 μm and massive Al-Fe brittle IMCs were found in the weld seam. When acceptable back weld appearance was obtained, a 20 μm IMCs layer was observed in the traditional MIG joint, which was extremely uneven and cracked after welding. Detailed analysis revealed that the uniform heating in thickness direction, preheating ahead of weld pool and differentiate heating of the HFAW-B process were beneficial to realize compatible regulation of interface characteristics and (back) weld appearance of Al/steel joint, i.e., to achieve not only a good weld appearance but also a thin compound layer under a low heat input. Benefitted from the sound weld appearance, thin interfacial IMCs layer and uniform stress distribution, the HFAW-B joint necked at Al side, and presented a tensile strength exceeded 90 % the strength of Al base metal.

Carvacrol is an effective antimicrobial agent originated from essential oils, this natural antimicrobial agent has higher consumer acceptance compared to chemical agents. Due to the low solubility of carvacrol in water, carvacrol was delivered as a nanoemulsion. A carvacrol nanoemulsion contained 3.5% (w/w) oil phase (1% carvacrol and 2.5% corn oil, w/w) and 3.5% (w/w) Tween 80 was produced by ultrasonification at 10 min using 100% amplitude; the median particle size was 309 ± 19 nm. The nanoemulsion was shelf-life stable for 1 month without any significant changes in particle size. When applied against Escherichia coli ATCC 25922 and Pichia pastoris GS115 growth in nutrient broth, carvacrol nanoemulsion (0.5% w/w carvacrol) achieved 3 log reductions of microorganisms. When microorganisms were fixed and dried on stainless steel coupon surface, the carvacrol nanoemulsion treatment was more effective on E. coli than P. pastoris with about 5 and 0.3 log reduction of viable count, respectively. The native microflora on shredded cabbages was challenged by combining carvacrol nanoemulsion and acidic electrolysed water (AEW) that contained ≤ 4 mg/L free available chlorine (FAC). The treatment reduced about 0.5 log of aerobic mesophilic and psychrotropic bacteria counts and the antimicrobial activity of carvacrol nanoemulsion and AEW lasted up to 2 days. The results indicated that carvacrol nanoemulsion is promising in controlling the safety of fresh-cut vegetables.

The effects of low-concentration electrolysed water (LcEW) (4 mg/L free available chlorine) combined with mild heat on the safety and quality of fresh organic broccoli (Brassica oleracea) were evaluated. Treatment with LcEW combined with mild heat (50 °C) achieved the highest reduction in naturally occurring microorganisms and pathogens, including inoculated Escherichia coli O157:H7 and Listeria monocytogenes (P

Electrolysed water (EW) is an activated liquid with a high oxidation-reduction potential. EW causes oxidative damage to pathogenic microorganisms and as a result, may have utility in the food industry. The molecular mechanism of EW's action is not understood. In this study, we exposed Escherichia coli ATCC 25922 to a sub-lethal concentration of EW and examined structural and metabolic changes. Atomic force microscopy revealed that EW caused damage to E. coli membranes. To understand the metabolic responses to EW perturbations in of E. coli, multivariate data analysis of NMR spectroscopy demonstrated that EW significantly influenced the metabolic state. This included reducing nucleotide and amino acid biosynthesis, suppressing energy-associated metabolism, altering osmotic adjustment, and promoting fatty acid metabolism. The results enrich our understanding of E. coli metabolic changes caused by EW perturbation and support the effectiveness of the NMR metabolomics as a valuable tool to analyse and evaluate such a complex biological system.

Background The impact of remote ischaemic preconditioning (RIPC) on major clinical outcomes in patients undergoing cardiovascular surgery remains controversial. We systematically reviewed the available evidence to evaluate the potential benefits of RIPC in such patients. Methods PubMed, Embase, and Cochrane Library databases were searched for relevant randomised controlled trials (RCTs) conducted between January 2006 and March 2016. The pooled population of patients who underwent cardiovascular surgery was divided into the RIPC and control groups. Trial sequential analysis was applied to judge data reliability. The pooled relative risks (RRs) with 95% confidence intervals (CIs) between the groups were calculated for all-cause mortality, major adverse cardiovascular and cerebral events (MACCEs), myocardial infarction (MI), and renal failure. Results RIPC was not associated with improvement in all-cause mortality (RR, 1.04; 95%CI, 0.82–1.31; I 2 =26%; P>0.05) or MACCE incidence (RR, 0.90; 95%CI, 0.71–1.14; I 2 =40%; P>0.05) after cardiovascular surgery, and both results were assessed by trial sequential analysis as sufficient and conclusive. Nevertheless, RIPC was associated with a significantly lower incidence of MI (RR, 0.87; 95%CI, 0.76–1.00; I 2 =13%; P≤0.05). However, after excluding a study that had a high contribution to heterogeneity, RIPC was associated with increased rates of renal failure (RR, 1.53; 95%CI, 1.12–2.10; I 2 =5%; P≤0.05). Conclusions In patients undergoing cardiovascular surgery, RIPC reduced the risk for postoperative MI, but not that for MACCEs or all-cause mortality, a discrepancy likely related to the higher rate of renal failure associated with RIPC.

In this paper, we investigate the dynamical behavior of in-host viral models with humoral immunity and intracellular delays. For both models, using the method of Lyapunov functional, we establish that the global dynamics are determined by two threshold parameters R0 and R1. If R0 ⩽ 1, the uninfected equilibrium E0 is globally asymptotically stable, and the viruses are cleared. If R1 ⩽ 1 E 1 ∗ is globally asymptotically stable, and the infection becomes chronic but with no persistent B cells response. If R1 > 1, the infected equilibrium with B cells response E 2 ∗ is globally asymptotically stable, and the infection is chronic with persistent B cells response. Alone with some numerical simulations.

Background: In response to injury, adult human heart has limited regeneration capacity and progression to heart failure, while fetal heart has robust regenerative capacity. Long non-coding RNAs (IncRNAs) have been implicated in cardiac development or heart failure, but little is known about the role