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OBJECTIVE: To investigate the effect of corticosteroid on hospital mortality, hospital length of stay, and time of viral clearance in patients with severe and critical COVID-19. PATIENTS AND METHODS: Patients with severe and critical COVID-19 who had been discharged or expired were enrolled in this study. Patients were divided into corticosteroid group and non-corticosteroid group according to the systemic corticosteroid use or not. Clinical data were collected, and hospital mortality, hospital length of stay, time of viral clearance, time of mechanical ventilation, and duration from illness onset to symptom resolution were compared between the two groups. RESULTS: A total of 72 inpatients who were diagnosed with severe and critical COVID-19 were enrolled, in which 47 patients were divided into corticosteroid group and 25 were involved as the non-corticosteroid group. Baseline characteristics were generally similar between the two groups. Four (5.6%) patients died during hospitalization, and 68 (94.4%) were discharged. Among survivors, the mean duration time from admission to discharge was 19.5d (SD 7.05 d). The mean time of viral clearance among survivors was 17.5d (SD 7.67 d), with a maximum of 37 d, and a minimum of 5 d. Hospital mortality (4.3% vs. 8.0%), length of hospital stay (18.7d vs. 21.0d), and time of viral clearance (16.1d vs. 19.4d) had no significant difference between two groups (p>0.05). The duration of symptoms suffering was shorter in the corticosteroid group than non-corticosteroid group, with statistically significant difference (p<0.05). CONCLUSIONS: Corticosteroid therapy in patients with severe COVID-19 cannot reduce the hospital mortality, and is not associated with delayed viral clearance, but it could relieve the inflammatory storm and improve clinical symptoms in brief. Patients with severe COVID-19 could benefit from low-dose corticosteroid treatment. [ABSTRACT FROM AUTHOR]

We report the demonstration of polymer-based top-emitting diodes that employed environmentally stable cathode materials. The device employed an emissive polymer blend that we reported previously [Deng et al. Appl. Phys. Lett. 84, 3522 (2004)]. By constructing a semitransparent cathode using the stable metals Al and Ag, bright light emission through the top cathode was achieved. An index-matching overlayer deposited by spin coating was shown to enhance the transmission efficiency through the top electrode. Microcavity effects were observed for the device by replacing the indium tin oxide anode with Au, resulting in wavelength tunability of the device. [ABSTRACT FROM AUTHOR]

The parallel computing is used for optimization modelling on multi-level nested genetic algorithm with superior scale to improve efficiency of the algorithm of steel plate operation scheduling problem. A parallel multi-layer genetic algorithm was designed based on the analysis of the present nested algorithm, and some key problems in parallel algorithm implementation were solved. An experimental example was illustrated. The results showed that the speedup of the proposed parallel algorithm comes up to 3.144 on a computer with quad-core processer and the total execution time is shortened greatly. The parallel nested genetic algorithm can meet the requirement for actual operation period. [ABSTRACT FROM AUTHOR]

Size effect on the crystalline phase contents has been investigated for BaTiO3 ceramics and varied from 100 to 8 nm by means of X-ray diffraction and Raman spectroscopy techniques. Mixed phases of tetragonal and orthorhombic at room temperature were corroborated by Raman spectroscopy. Rietveld refinement for X-ray diffraction data revealed that a locally orthorhombic structure preceded the globally tetragonal form with the grain decreasing, and a modified brick wall model was used to predict the dielectric constant between 100 and 8 nm, which demonstrated that grain boundary effects, coexisted structures took the dominant role in determining the ultrafine nanocrystalline BaTiO3 ceramics dielectric constant. [ABSTRACT FROM AUTHOR]

Ternary Ti–B–C nanocomposite coatings were synthesized on a Si(100) wafer and stainless steel substrates from Ti and \B4\C targets, respectively, by multitarget magnetron cosputtering. Extensive measurements were taken to investigate the influences of deposition temperature and work pressure on microstructure, hardness, elastic modulus, residual stress, friction coefficient, and adhesion strength. The maximum hardness of 42 GPa occurred at the deposition temperature of 400 ^\circ\C and work pressure of 0.5 Pa. The hardest coating also showed the lowest residual stress and the highest critical load. These enhancement effects should be related to nanocrystalline structure formation. [ABSTRACT FROM AUTHOR]

ZrB2, W, WNx coatings and ZrB2/W, ZrB2/WNx multilayered coatings have been synthesized by ion beam assisted deposition at room temperature. X-ray diffraction (XRD), XP-2 surface profiler, scanning electron microscopy (SEM) and nano indenter were employed to investigate the influence of modulation periods and N+ beam bombardment on microstructure and mechanical properties of the coatings. The low-angle XRD patterns and cross-sectional SEM indicate a well-defined composition modulation and layer structure of the multilayers. The multilayers with modulation periods ranging from 9 to 16 nm without N+ bombardment possessed higher hardness and elastic modulus than the rule-of-mixtures value of monolithic ZrB2 and W coatings. The highest hardness was 24 GPa. N+ bombardment to growing multilayers gave a significant contribution to mechanical property enhancement. When modulation period is 9.6 nm, ZrB2/WNx multilayer with 200 eV N+ bombardment reveals the highest hardness (30.2 GPa) and elastic modulus. This hardest multilayer also showed the improved residual stress and fracture resistance. [ABSTRACT FROM AUTHOR]

CNx/TiAlN multilayered coatings with different nanoscale modulation periods and ratio of CNx within each period were prepared by ion-beam-assisted deposition at room temperature. Auger electron spectroscopy (AES), x-ray diffraction (XRD), and nanoindenter and a profiler were used to characterize the microstructure and mechanical properties of the coatings. The low-angle XRD pattern and AES indicated a well-defined multilayered structure of the coating. Although monolithic CNx and TiAlN coatings formed amorphous and nanocrystalline structures, respectively, the CNx/TiAlN multilayers exhibited coherent epitaxial growth due to the mutual growth-promoting effect at small CNx layer thickness (<0.6 nm). At modulation period Λ=2.83 nm and CNx thickness of 10% within each period, the multilayers exhibited strong TiAlN (111) and weak AlN (111) textures and showed the highest hardness (32 GPa), elastic modulus (409 GPa), and critical fracture load (65.7 mN). [ABSTRACT FROM AUTHOR]

We investigated the preparation of bulk dense nanocrystalline BaTiO3 and Ni–Cu–Zn ferrite ceramics using an unconventional two-step sintering strategy, which offers the advantage of not having grain growth while increasing density from about 75% to above 96%. Using nanosized powders, dense ferrite ceramics with a grain size of 200 nm and BaTiO3 with a grain size of 35 nm were obtained by two-step sintering. Like the previous studies on Y2O3, the different kinetics between densification diffusion and grain boundary network mobility leaves a kinetic window that can be utilized in the second-step sintering. Evidence indicates that low symmetry, ferroelectric structures still exist in nanograin BaTiO3 ceramics, and that saturation magnetization is the same in nanograin and coarse grain ferrite ceramics. [ABSTRACT FROM AUTHOR]

Optimizing endothelial cell growth and adhesion on the surface of metallic stents implanted in the vascular system is a fundamental issue in understanding and improving their long-term biocompatibility. The ability of the endothelial cell to attach and adhere to the luminal stent surface as well as the capacity to withstand the significant shear stress associated with blood flow are important determinants. The adhesive characteristics of human umbilical vein endothelial cells (HUVEC) on stent surfaces coated with either Poly-L-Lysine (PLL) or fibronectin (FN) were compared with uncoated controls. Increasing concentrations of PLL and FN were measured using a micropipette aspiration system. The adhesive properties of HUVECs under static flow conditions were compared to a dynamic environment on endovascular stents using a parallel-plate-flow chamber. A scanning electron microscope picture was used to measure the number and the adhesive cell ratio as well as the percentage of surface coverage of stent by endothelial cells. The adhesive forces of HUVECs on foreign surfaces coated with PLL and FN were higher compared to uncoated surfaces, and were dependent on increasing concentrations. These coatings resulted in significant increase of the adhesive force of HUVECs. The influence of substrates on the adhesion of the endothelial cell monolayer under static or dynamic flow conditions was highly significant compared with controls (p <0.01). No significant differences were observed between PLL and FN substrates. Both PLL and FN coated surfaces can significantly increase the adhesion and growth of HUVECs on metallic stent surfaces. [ABSTRACT FROM AUTHOR]

Micromagnetic simulations of Co domain walls on nanometer crossbars that join two oppositely magnetized parallel legs of “H” shaped patterns are studied. The crossbar domain walls can twist in the plane of the H-pattern, out of the plane, or swirl, forming Néel, Bloch, or vortex structures, respectively, depending on the initial configurations. An energy phase diagram as a function of the crossbar constriction yields the Néel wall as the energetically most favorable, followed by the Bloch wall, which becomes unstable and changes into a vortex-like wall with increasing crossbar size. Most interestingly, the Néel wall width can either shrink or expand depending on the crossbar dimensions. In the case that both the crossbar length and width are small, desirable, ultranarrow domain walls can be obtained. These findings are useful for spintronic device design based on domain wall pinning via nanonotch and domain-wall magnetoresistance approaches. [ABSTRACT FROM AUTHOR]

ZrN/TiAlN multilayers with various modulation periods and ratios were grown by ion beam assisted deposition. The nanoscale multilayered modulation was confirmed by Auger electron spectroscopy. All multilayers possess higher hardness than the rule-of-mixture value of monolithic coatings. These properties critically depend on both modulation period and ratio. The multilayer with modulation period of 6.5 nm and ratio of 2:3 displays the highest hardness (>30 GPa) and critical fracture load (53.3 mN). These improvements in properties are likely the result of nanoscale strain optimization as the evolution of layer crystallinity finally reaches the formation of (111) textures in all layers. [ABSTRACT FROM AUTHOR]

The authors present a method for fabricating three-color polymer light-emitting devices by low-cost spin-coating and dry photopatterning processes. This method employed two emissive polymer layers in tandem, with each layer separately patterned by a photo-oxidation process. Different combinations of the two patterned layers give rise to the three primary colors, with the emission spectrum of each color essentially the same as that from individual constituent red-, green-, or blue-emitting polymers, and with luminous efficiencies comparable to that from the corresponding standard single-color devices. This method may provide a low-cost, high throughput procedure to manufacture polymeric flat-panel display devices. [ABSTRACT FROM AUTHOR]

We report that an ultrathin layer of tris-(8-hydroxyquinoline) aluminum (Alq[sub 3]) interposed between a bilayer cathode of LiF/Al and an emissive layer can significantly improve electroluminescence efficiency in a polymer light-emitting device (PLED). At a current density of 35 mA/cm², a poly[2-methoxy-5-(2'-ethyl-hexyloxy)-l,4-phenyl-enevinylene] (MEH-PPV)-based PLED with a cathode of Alq[sub 3]/LiF/Al has a quantum efficiency of 2.5%, considerably higher than that of a MEH-PPV-based PLED with a bare A1 or a LiF/A1 cathode. Interfacial characteristics of MEH-PPV/ LiF/A1 and MEH-PPV/Alq[sub 3]/LiF/A1 were investigated by photoelectron spectroscopy, and the results were used to explain the difference in device performance. [ABSTRACT FROM AUTHOR]

BACKGROUND AND PURPOSE 3-Hydroxy-octanoate, recently identified as a ligand for, the orphan GPCR, HCA(3), is of particular interest given its ability to treat lipid disorders and atherosclerosis. Here we demonstrate the pathway of HCA(3)-mediated activation of ERK1/2. EXPERIMENTAL APPROACH Using CHO-K1 cells stably expressing HCA(3) receptors and A431 cells, a human epidermoid cell line with high levels of endogenous expression of functional HCA(3) receptors, HCA(3)-mediated activation of ERK1/2 was measured by Western blot. KEY RESULTS HCA(3)-mediated activation of ERK1/2 was rapid, peaking at 5 min, and was Pertussis toxin sensitive. Our data, obtained by time course analyses in combination with different kinase inhibitors, demonstrated that on agonist stimulation, HCA(3) receptors evoked ERK1/2 activation via two distinct pathways, the PLC/PKC pathway at early time points (≤ 2 min) and the MMP/ epidermal growth factor receptor (EGFR) transactivation pathway with a maximum response at 5 min. Furthermore, our present results also indicated that the βγ-subunits of the G(i) protein play a critical role in HCA(3)-activated ERK1/2 phosphorylation, whereas β-arrestins and Src were not required for ERK1/2 activation. CONCLUSIONS AND IMPLICATIONS We have described the molecular mechanisms underlying the coupling of human HCA(3) receptors to the ERK1/2 MAP kinase pathway in CHO-K1 and A431 cells, which implicate the G(i) protein-initiated, PLC/PKC -and platelet-derived growth factor receptor/EGFR transactivation-dependent pathways. These observations may provide new insights into the pharmacological effects and the physiological functions modulated by the HCA(3)-mediated activation of ERK1/2., (© 2012 The Authors. British Journal of Pharmacology © 2012 The British Pharmacological Society.)

Carbon nanotubes (CNTs) are a class of new allotrope of carbon. Different functionalized CNTs may vary from their physical and chemical properties to the biological property. In this study, the toxicity of water-soluble taurine multi-walled CNTs (tau-MWNTs), raw MWNTs and positive control crystalline silicon dioxide particles on mouse lungs via intratracheal instillation (i.t.) was investigated. The dosages we used were 0.125, 0.25, 0.5 or 1 mg/kg of tau-MWNTs and raw MWNTs, and 1 mg/kg of silicon dioxide particles; Serum and lungs were collected at 1, 7, 14 or 28 days postexposure. The biochemical and cellular parameters were assessed, which include the ratio of the lung weight and body weight (lung indices), lactate dehydrogenase (LDH), alkaline phosphatase (ALP) and angiotensin converting enzyme (ACE) in serum, and malondialdehyde (MDA), reduced glutathione (GSH), total sulfhydryl group (TSH) in lung tissue homogenates as well as the hydroxyproline in lungs. The characteristic recovery of the lung injury at 28 days postexposure was examined by the assessment of LDH, ALP, lung indices, and histopathology. ACE, MDA, GSH, TSH and histopathological changes showed that tau-MWNTs were less toxic than the raw MWNTs. Histopathological and ultrastructural investigation indicated that the acute pulmonary inflammation in lungs alleviated after 7d postexposure, and were greatly recovered within 28d. Meanwhile, the entrapment of tau-MWNTs reduced greatly by the 28d postexposure. Whereas the heavier pathologic changes induced by raw MWNTs lasted 7 days more than that of tau-MWNTs. Notably, no occurrence of granulomas and fibrosis were found in this study both in the two CNTs samples through 28d postexposure. Silicon dioxide particles, on the contrary, produced more severe damage to lungs than CNTs did in lung index, as well as other biochemical and cellular parameters. These findings indicate that water-soluble tau-MWNTs in low and medium doses induce slight and recoverable pulmonary inflammation in mice, and are less toxic than the insoluble raw MWNTs.

In this work, we focus on the diameter effects on cytotoxicity of different diametered multi-walled carbon nanotubes (MWNTs). Cellular viability, phagocytotic ability, and apoptosis of guinea pig alveolar macrophages (AM) exposed to MWNTs were studied. MWNTs in smaller diameter showed less cytotoxicity than the larger ones at the same dosage. The phagocytosis ability of AM was partially impaired when the concentration of MWNTs was up to 20 microg/ml, where a further characteristic feature of AM apoptosis was observed. The results indicate that MWNTs in different diameters exhibited quite different cytotoxicity, and for the first time revealed the diameter-effect of MWNTs on cytotoxicity.

To further clarify the priming mechanism of liver regeneration, proteins and protein complexes from rat plasma (normal group, partial hepatectomy (PHx) group and sham-operation group) were comparatively studied by two-dimensional gel electrophoresis and two-dimensional blue native gel electrophoresis. Our results suggested that Kupffer cell--NF-kappaB/ROS might trigger the liver regeneration.

A specific, simple and sensitive HPLC method with UV detection was developed and validated for the pharmacokinetic studies of indirubin in rat plasma for the first time. Indirubin, with osthole as the internal standard, was extracted from plasma samples by liquid-liquid extraction. Chromatographic separation was conducted on a reverse-phase ODS column (200 mm x 4.6 mm, i.d., 5 microm), using a mixture of methanol-water (75:25, v/v) as the mobile phase at a flow rate of 1.0 ml/min with UV detection at 289 nm. The calibration curve of indirubin was linear over the range of 6.5-1950 ng/ml in rat plasma. The lower limit of quantification (LLOQ) was found to be 6.5 ng/ml. The present method was successfully applied for estimating the pharmacokinetic parameters of indirubin following intravenous and intraperitoneal administration of indirubin to rats.

Recently we confirmed that latent membrane protein 1 (LMP1) encoded by Epstein-Barr virus (EBV) accelerates a newly forming active c-Jun/Jun B heterodimer, a transcription factor, but little is known about the target gene regulated by it. In this paper, results indicated that a c-Jun/Jun B heterodimer induced by LMP1 upregulated cyclin D1 promoters activity and expression, on the contrary, downregulated p16, and maladjustment of cyclin D1 and p16 expression accelerated progression of cell cycle. Firstly, we found a c-Jun/Jun B heterodimer regulated synchronously and directly cyclin D1 and p16 in the Tet-on-LMP1-HNE2 cell line, in which LMP1 expression is regulated by Tet-on system. This paper investigated in depth function of the newly forming active c-Jun/Jun B heterodimer, and built new connection between environmental pathogenic factor, signal transduction and cell cycle.

The primary factors that predispose humans to the development of alcoholic pancreatitis are unknown. One of the earliest observations in humans in whom this disease develops is pancreatic hypersecretion caused by unknown mechanisms. Messenger RNA (mRNA) differential display was performed in a rat model to investigate the molecular mechanisms associated with ethanol-induced pancreatic hypersecretion. Male Wistar rats were pair-fed Lieber-DeCarli diets with or without ethanol for 7 days or 4 weeks. Total RNA was extracted from the pancreas and its neurohormonal control sites. Differentially expressed complementary DNA (cDNA) tags were isolated, cloned, and sequenced. One 248-bp cDNA was consistently and strongly induced in the pancreata of rats fed ethanol for 4 weeks. The sequence was highly homologous to both rat pancreatic monitor peptide (MP) and pancreatic secretory trypsin inhibitor (PSTI-56), also known as serine protease inhibitor, Kazal type 1 (SPINK1). Confirmatory reverse-transcription-polymerase chain reaction showed that PSTI-56 expression remained unchanged, whereas MP mRNA levels were elevated more than four times in the pancreata of ethanol-fed rats. These results indicate that long-term ethanol ingestion increases MP mRNA levels in the rat pancreas. Because MP stimulates cholecystokinin release and cholecystokinin is an important stimulant of pancreatic secretion, the enhanced MP gene expression may contribute to pancreatic hypersecretion.