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OBJECTIVE: Cells answer to biochemical, electrical and mechanical signals in the environment, which regulate their behavior. Mechanical signals can propagate through mechanically stiff structures like focal adhesions (FAs). Zyxin, a LIM domain protein, is localized primarily at focal adhesion plaques. Growing evidence suggests that zyxin is a vital mechanotransductor to regulate the gene expression. In this review, we summarize the features of zyxin and the molecular mechanism of how zyxin participate in the cellular activity. MATERIALS AND METHODS: An English-language literature search is based on a keyword- based query of multiple databases (MEDLINE, Embase) and bibliographies from identified publications. The references in the selected paper are also considered as an additional source of data. The search was last updated in April 2018; no limitations are applied. RESULTS: Zyxin enhances actin polymerization with the aid of Enabled (Ena)/vasodilator- stimulated phosphoprotein (VASP) proteins in response to mechanical tension, to perform its role in stress fibers (SFs) remodeling and repair. Zyxin can translocate from focal adhesions (FAs) to the nucleus responds to stretch, and regulate gene transcription by interaction with transcription factors like nuclear matrix protein 4 (NMP4). Misregulation of nuclear functions of zyxin appears to be associated with pathogenic effects and diseases, such as prostate cancer and non-small-cell lung cancer. CONCLUSIONS: Zyxin is a crucial ingredient of the cellular mechanotransducing system and can modulate the gene expression. Given its clinical relevance, zyxin is also a promising target for the diagnosis and treatment of certain diseases. Understanding the role of zyxin in force sensing and gene expression regulating provides a compelling challenge for future biomechanics studies, and offers attractive evidence for zyxin as a potential diagnostic marker and therapeutic target for clinical diseases. [ABSTRACT FROM AUTHOR]

Abstract: A 10‐week growth trial was run to evaluate effects of myo‐inositol (MI) on growth performance, haematological parameters, antioxidative capacity and salinity stress tolerance of Litopenaeus vannamei. Six practical diets supplemented with graded levels of MI (designated as MI0, MI600, MI1200, MI2400, MI 3600 and MI4800 for 448.8, 974.2, 1568.0, 2810.6, 3835.5 and 4893.6 mg/kg diet, respectively) were fed to six replicate groups of L. vannamei (mean initial body weight 0.63 ± 0.00 g). The results showed that significant increment of growth performance was observed in shrimp fed MI600 diet than those fed MI1200 diet. Lipid concentration in whole body of the shrimp fed MI600 diet was significantly increased. Shrimp fed MI0 diet had lower total protein (TP) as compared to shrimp fed the MI‐supplemented diets (except MI4800 diet). In general, lower activities of antioxidant enzymes and higher malondialdehyde (MDA) content in haemolymph and hepatopancreas were recorded in shrimp fed MI0 diet, compared to those fed the MI‐supplemented diets. Reduced survival after 7‐h salinity stress was present in shrimp fed MI0 diet as compared to those fed MI4800 diet. Dietary MI requirement for glutathione peroxidase activity of L. vannamei was 2705 mg/kg diet. [ABSTRACT FROM AUTHOR]

Cast iron with good mechanical and thermal combination property is preferred material for the cylinder head of high power density diesel engine. Interface between graphite and matrix should play a key role in thermal conductivity of cast iron. However, it is difficult to measure the interfacial contact thermal conductance (ICTC) between graphite inclusion and matrix in cast iron. In this paper, a modeling experimental sample containing a macroscopic interface is designed and ICTC can be estimated with the aid of finite element (FE) calculation. At last the effect of ICTC on the thermal conductivity of cast iron is assessed according to the change of metallographic FE simulation results before and after considering ICTC. Results show that the magnitude of ICTC is between 1.0 × 105 and 2.0 × 105 W m−2·K on the whole. The interface makes the theoretical thermal conductivity of cast iron drop down 34.6%. [ABSTRACT FROM AUTHOR]

(Ti, Zn)-co-doped Bi0.97Nd0.03FeO3(BNFTZ) thin films with different thicknesses were prepared directly on indium tin oxide/glass substrates deriving from the precursor solutions with different solution concentrations. The X-ray diffraction, scanning electron microscopy and insulating/ferroelectric/dielectric measurements were utilised to characterise the BNFTZ thin films. Both BNFTZ thin films with the thicknesses of 160 and 320 nm are crystallised into phase-pure perovskite structure without second phase. Compared to the film of 160 nm, a lower leakage current can be obtained in BNFTZ film of 320 nm due to due to its denser microstructure with smaller grain size. The film with 320 nm thickness possesses a high energy-storage efficiency of 87%, which can be ascribed to the slimP–Eloop. At 100 kHz, the film of 320 nm owns lower dielectric constant (~91) and dissipation factor (~0.10). The possible contributions are discussed to explain the difference in the related performances for BNFTZ thin films with different thicknesses. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To analyze how changes in the levels of brain-derived neurotrophic factor (BDNF) and neuroglobin (NGB) affect learning and memory in rats with intracerebral hemorrhage. MATERIALS AND METHODS: Thirty male Sprague-Dawley rats were randomly divided into the control group, sham operation group and model group with 10 rats each. The rats in the control group were untreated, while those in the sham operation group were treated with sterile saline instead of type VII collagenase injection in the globus pallidus. The model of cerebral hemorrhage was established according to the methods described by Rosenberg. The expression of perihematomal BDNF mRNA was measured by Real-time quantitative PCR (RT-PCR) for 7 days consecutively. Perihematomal NGB-positive cells were detected by immunohistochemistry. The Morris water maze was used to test the spatial learning and memory of rats. RESULTS: Compared with the control group and sham operation group, the expression of BDNF mRNA and number of NGB-positive cells in the model group were significantly higher. Furthermore, the escape latency was significantly prolonged (p < 0.05). The NGB and BDNF mRNA levels and escape latency were positively correlated. The correlation coefficients were as follows: rs (NGB) = 1.1838 (p = 0.008); rs (BDNF) = 0.5948 (p = 0.012). CONCLUSIONS: Cerebral hemorrhage significantly inhibited the spatial learning and memory ability of rats. The mechanism may be related to decreased cerebral expression of BDNF and NGB. [ABSTRACT FROM AUTHOR]

Concrete cover separation is a common failure mode of RC beams strengthened with a fiber-reinforced polymer (FRP) plate externally bonded to the tension face (FRP-plated RC beams). This failure mode initiates at the critical plate end and then propagates at the level of steel tension reinforcement in the direction of increasing moment. Plate-end anchorage by FRP U-jackets has been specified in some design guidelines as a mitigation measure to delay or suppress concrete cover separation, although its effectiveness is far from clear. This mitigation method is more attractive than other options because the same strengthening material is used and the installation procedure is simple. This paper presents the first systematic experimental study on the use of FRP U-jackets for mitigating plate-end concrete cover separation failure, with particular attention to the effect of inclination angle between the U-jacket and the beam axis. A total of 10 fullscale FRP-plated RC beams were tested. The test results show that both the load-carrying capacity and the ductility of an FRP-plated RC beam can be significantly enhanced by FRP U-jacketing at the critical plate end. Inclined U-jacketing at 45° to the beam axis was found to be much more effective than vertical U-jacketing (i.e., at 90° to the beam axis) in mitigating plate-end cover separation failure. [ABSTRACT FROM AUTHOR]