The diabetic milieu is believed to change the activity, or result in damage of podocytes-a key component of the glomerular filtration barrier and known to secrete matrix for glomerular basement membrane. This in turn contributes to diabetic nephropathy. However, how podocyte dysfunction is triggered in diabetic nephropathy remains ambiguous. Galectin-1 belongs to Galectin family that bind to β-galactoside residues of glycosylated proteins. We explored whether Galectin-1 is dysregulated in diabetic nephropathy using three different techniques, namely real-time polymerase chain reaction, western blotting, and immunofluorescent staining, to follow the expression of Galectin-1 under high glucose levels in podocytes. High glucose consistently induced Galectin-1 expression. Immunohistochemistry using a Galectin-1-specific antibody also showed elevated Galectin-1 in renal tissues of diabetic patients with manifestation of nephropathy, indicating a correlation of Galectin-1 overexpression with diabetic nephropathy. Upregulation of Galectin-1 is associated with loss of podocin, which is important for the physiological function of podocytes and decreases in the renal tissues of diabetic nephropathy. Increased Galectin-1 is a causal event for the high glucose-induced loss of podocin, since silencing Galectin-1 in podocytes increased podocin expression in the presence of 25 mM glucose. Thus expression of Galectin-1 in diabetic nephropathy may serve as a marker and contribute to disease progression by interfering with podocin expression.

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Laser beam machining is one of the most widely used advanced processing techniques, which can be applied to compound materials. As a large number of photons are absorbed into the composite, the subsequent local heat storage, charring and potential delamination make the study for the effect of laser on complex materials become significant. In this paper, a carbon fiber epoxy composite laminated sheet is irradiated by continuous wave chemical oxygen iodine laser. The peak temperature of front surface, the temperature distribution of rear surface, and the appearance of ablation zone are presented. Further, based on the birth-death elements technique of finite element method, a three-dimensional model for simulating the transient temperature distribution and material removal has been developed under the same condition. The results reveal that the peak temperature of irradiated region ranges from 2800 K to 3100 K, and the center point shows a higher temperature rise rate than the surroundings in the irradiated zone. The measured data and predicted data are in a good consistency, which suggests that the numerical model is appropriate for simulating laser ablation of carbon fiber epoxy composites.

In order to study on tensile and fatigue fracture mechanism of friction stir welded (FSW) joints, the tensile and fatigue behavior of FSW joints are studied based on the microstructure and strain distribution. The large plastic deformation and fracture occurred in the thermo-mechanically affected zone (TMAZ) on retreating side in tension tests. High contents of shear texture and small angle grain boundary reduce the tensile mechanical property of TMAZ material. The fatigue weak area for FSW joints is affected by the loading condition. The strain concentration in the welded nugget zone (WNZ) and base material makes the fatigue fracture liable to happen in these areas for the FSW joints under the stress ratios of 0.1 and −0.3. When the fracture occurred in WNZ, the crack initiation mainly occurred in clusters of hardened particles, while when the fracture happened in base material, the crack initiation mainly occurred near the pit. The crack in WNZ propagated in an intergranular pattern and the crack in the other areas extended in a transgranular mode, leading to a higher crack growth rate of WNZ than of other regions.