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Premature senescence of renal tubular epithelial cell (RTEC), which is involved in kidney fibrosis, is a key event in the progression of diabetic nephropathy. However, the underlying mechanism remains unclear. Here we investigated the role and mechanism of decoy receptor 2 (DcR2) in kidney fibrosis and the senescent phenotype of RTEC. DcR2 was specifically expressed in senescent RTEC and associated with kidney fibrosis in patients with diabetic nephropathy and mice with streptozotocin-induced with diabetic nephropathy. Knockdown of DcR2 decreased the expression of α-smooth muscle actin, collagen I, fibronectin and serum creatinine levels in streptozotocin-induced mice. DcR2 knockdown also inhibited the expression of senescent markers p16, p21, senescence-associated beta-galactosidase and senescence-associated heterochromatic foci and promoted the secretion of a senescence-associated secretory phenotype including IL-6, TGF-β1, and matrix metalloproteinase 2 in vitroand in vivo. However, DcR2 overexpression showed the opposite effects. Quantitative proteomics and validation studies revealed that DcR2 interacted with peroxiredoxin 1 (PRDX1), which regulated the cell cycle and senescence. Knockdown of PRDX1 upregulated p16 and cyclin D1 while downregulating cyclin-dependent kinase 6 expression in vitro, resulting in RTEC senescence. Furthermore, PRDX1 knockdown promoted DcR2-induced p16, cyclin D1, IL-6, and TGF-β1 expression, whereas PRDX1 overexpression led to the opposite results. Subsequently, DcR2 regulated PRDX1 phosphorylation, which could be inhibited by the specific tyrosine kinase inhibitor genistein. Thus, DcR2 mediated the senescent phenotype of RTEC and kidney fibrosis by interacting with PRDX1. Hence, DcR2 may act as a potential therapeutic target for the amelioration of diabetic nephropathy progression.

In this report, a new type of double-drive photoelastic modulation effect is studied. Two piezoelectric actuators are connected to a symmetric photoelastic crystal at an angle of 45°. The actuators and crystal have the same resonant frequency. By adjusting the amplitude and phase difference between the driving voltages of the two piezoelectric actuators, two special forms of photoelastic modulation can be realized, namely, a pure standing wave form and a pure traveling wave form. The retardation magnitude and the azimuth angle of the modulation fast axis can be regulated in the pure standing wave, and the modulation axis moves circumferentially in the pure traveling wave. We have experimentally observed the two special photoelastic modulation modes, and the test and calibration methods are also reported.

A rapid thermal annealing at 670° C is performed for 20 s on a titanium film (35 nm) on <0 0 1> silicon. Epitaxial growth of TiSi2of a C49 structure is induced by the annealing, when the substrate is heated to 400° C before titanium sputtering. In contrast, a fibre texture is obtained if the substrate is not heated. The in-plane orientations determined by X-ray and electron diffraction are in good agreement with those theoretically calculated using the method of the maximum number of coincidence sites at the epitaxial interface.

We apply the higher order Cauchy transforms to describe the closures of rational modules with respect to the LP norms, the uniform norm and different Lipschitz norms on a compact set in the plane.