The expression of cytokeratins 18 and 19 by human retinal pigment epithelial cells (HRPE) has been suspected of being associated with HRPE proliferation. We have investigated the involvement of these cytokeratin subtypes in the proliferative and migratory behaviour of cultured HRPE. Cell proliferation markers (bromodeoxyuridine and proliferating cell nuclear antigen) and the cytokeratins were i...

PURPOSE To examine the modulation of interleukin-1 beta (IL-1 beta)- and tumor necrosis factor-alpha (TNF-alpha)-stimulated monocyte chemotactic protein-1 (MCP-1) and interleukin-8 (IL-8) secretion and transcription in human retinal pigment epithelial (HRPE) cells by dexamethasone (DEX) and cyclosporin A (CSA). METHODS Cultured HRPE cells were stimulated with IL-1 beta (0.2 to 20 ng/ml) or TN...

PURPOSE To investigate the functional involvement of caspase-4 in human retinal pigment epithelial (hRPE) cells. METHODS Expression and activation of caspase-4 in hRPE cells were measured after stimulation with proinflammatory agents IL-1beta (2 ng/mL), TNF-alpha (20 ng/mL), lipopolysaccharide (1000 ng/mL), interferon-gamma (500 U/mL), or monocyte coculture in the absence or presence of immun...

PURPOSE To investigate the role of the phosphatidylinositol 3-kinase (PI3K) pathway and the signal mediator AP-1 in monocyte chemotactic protein (MCP)-1 and interleukin (IL)-8 gene expression in human retinal pigment epithelial (hRPE) cells. METHODS hRPE cells were stimulated with IL-1beta and TNF-alpha and by coculturing with monocytes in the presence or absence of a series of kinase inhibit...

Vertebrate eyes are known to contain circadian clocks, but their regulatory mechanisms remain largely unknown. To address this, we used a cell line from human retinal pigment epithelium (hRPE-YC) with stable coexpression of reporters for molecular clock oscillations (Bmal1-luciferase) and intracellular Ca2+ concentrations (YC3.6). We observed concentration-dependent increases in cytosolic Ca2+ ...

PURPOSE We aimed to elucidate the effects of two epigenetic inhibitors, 5-aza-2'-deoxycytidine (5-aza-dC) and trichostatin A (TSA), on several key secretory mediators of diabetic retinopathy (DR) in human retinal endothelial cells (HRECs) and human retinal pigment epithelial (HRPE) cells treated with high glucose or interleukin-1β (IL-1β). METHODS HRECs and HRPE cells were incubated in 30 mM ...

PURPOSE To determine the mechanism of oxidant-induced cell death in cultured human retinal pigment epithelium (hRPE). METHODS Cultured hRPE cells were treated with different concentrations of a chemical oxidant, t-butylhydroperoxide (tBH), for different periods of time. Apoptosis was determined with terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick-end labeling (TUNEL) and flow c...

A hyperbranched cationic polysaccharide derivative-mediated small interfering (si)RNA interference strategy was proposed to inhibit nuclear transcription factor-kappa B (NF-κB) activation in human retinal pigment epithelial (hRPE) cells for the gene therapy of diabetic retinopathy. Two hyperbranched cationic polysaccharide derivatives containing the same amount of cationic residues, but with di...

Proliferative vitreoretinopathy (PVR) is a common cause of intraoperative failure following retinal reattachment surgery and is mediated in part through the migration, de-differentiation and proliferation of retinal pigment epithelial (RPE) cells. Given the cytotoxic effects of curcumin on epithelial and endothelial cells, in this study, we assessed the effects of curcumin on human RPE (hRPE) c...

Estimating downlink (DL) channel state information (CSI) in frequency division duplex (FDD) massive multi-input multi-output (MIMO) systems generally requires pilots and feedback overheads. Accordingly, this paper investigates the feasibility of zero-feedback FDD MIMO based on extrapolation. We use high-resolution parameter estimation (HRPE), specifically space-alternating generalized expectati...