Search

Summary Insufficient trophoblast invasion often occurs in patients experiencing preeclampsia. The 67-kDa laminin receptor (LR1) is a multifunctional protein that binds to laminin and interacts with the extracellular matrix. We recently demonstrated that LR1 is implicated in trophoblast migration and invasion. However, whether LR1 is involved in hypoxia-mediated trophoblastic invasion remains unclear and requires further investigation. This study demonstrates that two trophoblast-like cell lines (JEG3 and BeWo cells) cultured at 3% oxygen exerted enhanced migratory and invasive capabilities as compared with their counterparts exposed to 20% oxygen. LR1 expression was increased in hypoxic JEG3 cells but decreased after transfection with hypoxia-inducible factor 1 alpha (HIF-1α) specific siRNA. Moreover, shRNA targeting LR1 mRNA significantly inhibited hypoxia-induced increase in matrix metalloproteinase (MMP)-9 activity in JEG3 cells. Forced overexpression of LR1 augmented JEG3 cell migration and invasion, and enhanced MMP-9 expression and activity. Additionally, the blockade of the MMP-9 effect with its neutralizing antibody reduced LR1 elevation-promoted trophoblastic invasion. In summary, this study demonstrates that LR1 contributes to hypoxia-induced migration and invasion of trophoblast cells at least partly by mediating MMP-9 in vitro.

A low order characteristic-nonconforming finite element method is proposed for solving a two-dimensional convection-dominated transport problem. On the basis of the distinguish property of element, that is, the consistency error can be estimated as order O(h2), one order higher than that of its interpolation error, the superclose result in broken energy norm is derived for the fully discrete scheme. In the process, we use the interpolation operator instead of the so-called elliptic projection, which is an indispensable tool in the traditional finite element analysis. Furthermore, the global superconvergence is obtained by using the interpolated postprocessing technique. Lastly, some numerical experiments are provided to verify our theoretical analysis. Copyright © 2013 John Wiley & Sons, Ltd.