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Lipopolysaccharide can induce myocardial cell injury, which has been widely used in the preparation of septic cardiomyopathy models. We herein aimed to evaluate the protective effects of sodium hydrosulfide against oxidative stress and endoplasmic reticulum stress on the cell model of septic cardiomyopathy and to explore whether the protein kinase RNA-like endoplasmic reticulum kinase-eukaryotic initiation factor 2 alpha signaling pathways was involved. The sepsis induced cardiomyopathy model which was established by inducing rat cardiomyoblast cell line H9c2 cells with lipopolysaccharide and sodium hydrosulfide and endogenous hydrogen sulfide inhibitor (DL-propargylglycine) were used for intervention treatment. Then, cell viability, endogenous hydrogen sulfide levels, lactate dehydrogenase, reactive oxygen species, superoxide dismutase, glutathione and malondialdehyde were determined using commercial assay kits; enzyme-linked immunosorbent assay was used to determine creatine kinase-myoglobin binding, interleukin-6, tumor necrosis factor alpha and interleukin-10; reverse transcription-polymerase chain reaction was used to determine cystathionine gamma-lyase messenger RNA expression; and Western blot was used to determine glucose-regulated protein 78, protein kinase RNA-like endoplasmic reticulum kinase, phosphorylated protein kinase RNA-like endoplasmic reticulum kinase, eukaryotic initiation factor alpha, phosphorylated eukaryotic initiation factor alpha, activating transcription factor 4 and C/EBP-homologous protein levels. Sodium hydrosulfide increased the hydrogen sulfide contents of cells, but did not affect the messenger RNA expression of cystathionine gamma-lyase. It attenuated the decrease in cell viability caused by lipopolysaccharide; reduced the release of the myocardial enzymes like lactate dehydrogenase and creatine kinase-myoglobin binding; reduced the level of inflammatory factors like interleukin-6 and tumor necrosis factor alpha; reduced the level of oxidative stress; inhibited the expression of protein kinase RNA-like endoplasmic reticulum kinase pathway proteins. Sodium hydrosulfide treatment improves septic cardiomyopathy by inhibiting oxidative stress and endoplasmic reticulum stress via the protein kinase RNA-like endoplasmic reticulum kinase-eukaryotic initiation factor alpha pathway, which may be a theory for the treatment of septic cardiomyopathy. [ABSTRACT FROM AUTHOR]

OBJECTIVE: We investigated the effect of electrical stimulation (ES) of varying pulse frequency on differentiation and proliferation of canine myloglossus satellite cells in vitro. MATERIALS AND METHODS: Cellular viability and proliferation were assayed using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetra-zoliumbromide (MTT) assay and flow cytometry fluorescence-activated cell sorting analysis. Cellular differentiation and expression of mark molecule were assayed by Real Time-PCR and Western blot. RESULTS: With increasing frequency ES, we found a significant increase in Myod (r=0.988, p<0.0001), myogenin (r=0.988, p<0.0001), My-HC-slow (r=0.988, p<0.0001), MyHC-fast (r=0.875, p<0.0001) protein expression, and Pax7 mRNA expression (r=0.712, p=0.001). CONCLUSIONS: Pax7 mRNA expression and MyoD, myogenin, and MyHC protein expression were increased with increment of electrical stimulation frequency in myloglossus muscle satellite. Higher frequency ES enhanced myloglossus satellite cell differentiation, not proliferation and viability. [ABSTRACT FROM AUTHOR]

OBJECTIVE: Intervertebral disc (IVD) degeneration (IDD) is a well-known consequence of low back pain, as characterized by aberrant cell proliferation and apoptosis of nucleus pulposus (NP) cells. In the present study, we aimed to investigate the effect of lncRNA small nucleolar RNA host gene 6 (SN-HG6) on deregulated functions of degenerative NP cells. MATERIALS AND METHODS: After the establishment of rat IDD models, the mRNA and protein levels of collagen-I (Col-I) and collagen II (Col-II), and mRNA level of SNHG6 were detected by using reverse transcription quantitative Real Time-PCR (RT-qPCR) and Western blot. We further investigated the role and molecular mechanisms of SNHG6 by overexpressing or silencing it in degenerative NP cells. Cell proliferation was measured by MTT assay and EdU staning, and apoptosis was measured by flow cytometry. The target of SNHG6 was identified by starBase and Dual-Luciferase reporter assay. RESULTS: Upregulation of SNHG6 was found in IDD NP cells than in normal cells, associated with higher level of Col-I and lower level of Col-II. Overexpression of SNHG6 inhibited cell proliferation and enhanced apoptosis, accompanied by increased expression of Bax, caspase-3, and p21, as well as decreased expression of Bcl-2, which was in reverse to the treatment of SNHG6 silencing. Moreover, miR-101-3p was indicated as a target of SNHG6, and inhibition of miR-101-3p reversed the effects on proliferation and apoptosis induced by SNHG6. CONCLUSIONS: SNHG6 suppressed cell proliferation and induced apoptosis by increasing expression of Bax, caspase-3, p21 and decreasing Bcl-2 through targeting miR-101-3p, which suggested that SNHG6 could be a potential target in the treatment of IDD. [ABSTRACT FROM AUTHOR]

The interfaces between graphene and graphane play an important role in developing graphene-graphane-based electronic devices. We identify three most common types of graphane-graphene interface, and perform atomistic simulations to determine three key parameters that characterize the interface structural properties: mismatch strain, tilt angle, and interfacial stress. Further through atomistic simulations, we find that the composite sheets can develop complex morphologies, such as ripples, warps and wedges. These morphologies can be accurately reproduced by our finite-element modeling with interfacial properties explicitly included. We further show that mismatch in the lattice parameters between graphene and graphane is the dominant factor that causes the complex morphologies. Our work provides a quantitative framework for analyzing and designing graphene-graphane composite sheet architectures, and further for exploring their electronic properties. [ABSTRACT FROM AUTHOR]

Examines the spatial distribution of the superconducting properties of high Curie temperature thin films. Value of the maximum local critical current density; Electron-beam irradiation of the thin film sample; Use of the four-probe transport measurement of the critical current density.

Presents a study that observed the harmonic mixing experiments in the waveband. Use of a high temperature superconducting grain boundary Josephson junction; Purpose of the study; Dependencies of intermediate frequency output on direct current bias, harmonic number and frequency of local oscillator.

Experimental evidence of the existence of multi-wall platinum (Pt) nanowires (NWs) has been reported. In this paper, we investigated structural formation of Pt NWs using the classical molecular dynamics (MD) simulation method. The simulations began from initial configurations with random distributions of atomic positions. The initial configuration was minimised by the steepest descent method, and assigned a temperature of 601 K with a random distribution of atomic velocities. Then simulated annealing was applied such that the temperature of the system was reduced gradually to I K and a stable NW structure was obtained. Types of hexagonal solid Pt NWs featuring different structures than those of previously reported NWs were found. Details of structural characteristics and mechanical properties of these Pt NWs are presented. [ABSTRACT FROM AUTHOR]

Derived expressions of equivalent elastic constants of a truss-core sandwich panel are presented in this paper. The truss-core sandwich panel is similar to conventional sandwich systems, but the panel eliminates most of the attendant problems associated with the fabrication process of conventional sandwich systems. The 3-D trusscore sandwich panel is transformed into an orthotropic thick plate continuum for which 2- D closed-form and 2-D finite element solutions are obtained. Comparison of closed-form solution and finite element results showed good agreement. Using closed-form solution, deflection coefficients are computed and presented in the form of data tables to aid rapid assessment of maximum elastic deflection of truss-core panels; linear interpolation allows the response to be determined, and from which effective preliminary design may proceed without hindrance. [ABSTRACT FROM PUBLISHER]

Under increasing tensile load, the lifetime of a single catch bond counterintuitively increases up to a maximum and then decreases exponentially like a slip bond. So far, the characteristics of single catch bond dissociation have been extensively studied. However, it remains unclear how a cluster of catch bonds behaves under tensile load. We perform computational analysis on the following models to examine the characteristics of clustered catch bonds: (i) clusters of catch bonds with equal load sharing, (ii) clusters of catch bonds with linear load sharing, and (iii) clusters of catch bonds in micropipette-manipulated cell detachment. We focus on the differences between the slip and catch bond clusters, identifying the critical factors for exhibiting the characteristics of catch bond mechanism for the multiple-bond system. Our computation reveals that for a multiple-bond cluster, the catch bond behaviour could only manifest itself under relatively uniform loading conditions and at certain stages of decohesion, explaining the difficulties in observing the catch bond mechanism under real biological conditions.

Several mechanisms have been proposed in the literature to explain the robust attachment and rapid, controllable detachment of geckos' feet on vertical walls or ceilings, yet, it is still debatable, which one is ultimately responsible for geckos' extraordinary capabilities for robust and reversible adhesion. In this paper, we re-examine some of the key movements of geckos' spatula pads and seta hairs during attachment and detachment, and propose a sequence of simple mechanical steps that would lead to the extraordinary properties of geckos observed in experiments. The central subject under study here is a linear distribution of pre-tension along the spatula pad induced by its sliding motion with respect to a surface. The resulting pre-tension, together with a control of setae's pulling force and angle, not only allows for robust and strong attachment, but also enables rapid and controllable detachment. We perform computational modelling and simulations to validate the following key steps of geckos' adhesion: (i) creation of a linear distribution of pre-tension in spatula through sliding, (ii) operation of an instability envelope controlled by setae's pulling force and angle, (iii) triggering of an adhesion instability leading to partial decohesion along the interface, and (iv) complete detachment of spatula through post-instability peeling. The present work not only reveals novel insights into the adhesion mechanism of geckos, but also develops a powerful numerical simulation approach as well as additional guidelines for bioinspired materials and devices.