438 research outputs found
Effect of bone morphogenetic protein-2 on diabetic retinopathy and its mechanism of action
Purpose: To investigate the effect of bone morphogenetic protein-2 (BMP-2) on human retinal vascular endothelial cells (RECs) and human retinal pigment epithelial cells (RPE) cultured in high glucose (HG) in vitro, and the underlying mechanism.
Methods: Cell counting kit-8 (CCK-8) was used to determine cell proliferation while Western blot was used to assay the expressions of extracellular matrix and angiogenesis-related factors, Expressions of cytokines and chemokines were assessed by quantitative real time polymerase chain reaction (qRTPCR) and enzyme-linked immunosorbent assay (ELISA). Changes in Smad, ERK, JNK and p38MAPK signal pathway were measured by transfection and interference.
Results: The level of expression of BMP-2 in HG group was higher than that in normal glucose (NG) culture group. The expressions of angiogenesis-related factors i.e. vascular endothelial growth factor (VEGF) and intercellular cell adhesion molecule-1 (ICAM1), pro-inflammatory factors i.e. IL-6 and chemokine monocyte chemokine protein-1 (MCP1), increased significantly in HG group compared to NG and HG + BMP-2 groups. Phosphorylation of Smad1/5/8 and activation of ERK, JNK and p38MAPK signaling pathways were enhanced by BMP-2.
Conclusion: These results suggest that BMP-2 promotes angiogenesis and enhances the expressions of inflammatory cytokines via Smad signaling pathway
Hyperbolic Circle Packings and Total Geodesic Curvatures on Surfaces with Boundary
This paper investigates a generalized hyperbolic circle packing (including
circles, horocycles or hypercycles) with respect to the total geodesic
curvatures on the surface with boundary. We mainly focus on the existence and
rigidity of circle packing whose contact graph is the -skeleton of a finite
polygonal cellular decomposition, which is analogous to the construction of
Bobenko and Springborn [4]. Motivated by Colin de Verdi\`ere's method [6], we
introduce the variational principle for generalized hyperbolic circle packings
on polygons. By analyzing limit behaviours of generalized circle packings on
polygons, we give an existence and rigidity for the generalized hyperbolic
circle packing with conical singularities regarding the total geodesic
curvature on each vertex of the contact graph. As a consequence, we introduce
the combinatoral Ricci flow to find a desired circle packing with a prescribed
total geodesic curvature on each vertex of the contact graph.Comment: 26 pages, 7 figure
Distributed State Fusion Kalman Predictor Based on WLS Algorithm
AbstractBased on the weighted least square (WLS) algorithm, a unified multisensor distributed state fusion estimation criterion is presented in this paper, which includes the optimal weighted fusion algorithms weighted by matrices, scalars and diagonal matrices as the special cases. Furthermore, the corresponding optimal distributed state fusion Kalman predictor is presented for the multisensor linear discrete time-varying stochastic control systems with different measurement matrices and correlated noises. A simulation example for a tracking system with 3-sensor shows its effectiveness
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