No abstract

Epigallocatechin-3-gallate (EGCG) is a major polyphenol component of green tea (Camellia sinensis) and demonstrates anti-oxidant, anticancer and anti-inflammatory properties. EGCG has been shown to protect retinal pigment epithelium (RPE) against oxidative stress-induced cell death. The pathogenesis of diseases in the retina is usually initiated by local inflammation at the RPE cell layer, and inflammation is mostly associated with leukocyte migration and the secretion of pro-inflammatory cytokines. Whether EGCG can modulate the cytokine-induced inflammatory response of RPE, particularly leukocyte migration, has not been clearly elucidated, and was therefore the objective of this study. ARPE-19 cells were cultured with different concentrations of TNF-α in the presence or absence of EGCG to different time points. Intracellular reactive oxygen species (ROS) levels were determined. Intercellular adhesion molecule (ICAM)-1 and phosphor-NF-κB and IκB expression were determined by Western blot analysis. Phosphor-NF-κB nuclear translocation and monocyte-RPE adhesion were investigated using immunofluorescence confocal laser scanning microscopy. Scanning electron microscopy (SEM) was carried out to further determine the ultrastructure of monocyte-RPE adhesion. The results demonstrated that TNF-α modulated inflammatory effects in ARPE-19 by induction of ROS and up-regulation of ICAM-1 expression. Moreover, TNF-α-induced phosphor-NF-κB nuclear translocation, increased phosphor-NF-κB expression and IκB degradation, and increased the degree of monocyte-RPE adhesion. Pretreating the cells with EGCG ameliorated the inflammatory effects of TNF-α. The results indicated that EGCG significantly exerts anti-inflammatory effects in ARPE-19 cells, partly as a suppressor of TNF-α signaling and that the inhibition was mediated via the NF-κB pathway.

Introduction Occupation-based practice is a core tenet of occupational therapy. This study explores perspectives and experiences with occupation-based practice among Thai occupational therapists. Method Using mixed methods, a focus group was conducted with eight occupational therapists, and the results were interpreted using thematic analysis. A questionnaire survey was also completed concerning practitioner perspectives ( n = 216). Findings Three major themes were identified: (a) perspectives on occupation-based practice were related to practice areas and felt to strengthen the identity of occupational therapy (52% strongly agree), leading to improved services and better outcomes for clients (44% strongly agree); (b) approaches focused on activities of daily living were appropriate for cross-practice areas; and (c) occupation-based practice is consistent with integrated medical sciences and occupations for clients (52% strongly agree). Conclusion Implementing occupation-based practice will be of value to clients, provide benefits as a compass to direct processes, and enhance clinical reasoning and outcomes.

Epigallocatechin-3-gallate (EGCG), the most abundant polyphenolic flavonoids in green tea has been shown to possess strong antioxidant activities. Oxidative stress causes the defect of retinal pigment epithelial (RPE) cells that contribute to several retinal diseases. Several studies have shown that increasing the body's defenses against oxidative stress with specific antioxidants and mineral supplements could preserve the vision. Therefore, the purpose of this study was to determine the protective role of EGCG against exogenous reactive oxygen species hydrogen peroxide (H 2 O 2 )-induced cell death in ARPE-19 cells, human retinal pigment epithelial cell line. ARPE-19 cells were pretreated with EGCG in the presence/absence of H 2 O 2 . The protective effects of EGCG and the underlined mechanisms against H 2 O 2 were evaluated. The present study demonstrated that 400 µM H 2 O 2 significantly decreased cell viability, increased the accumulation of intracellular reactive oxygen species (ROS) and increased the number of terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL)-positive cells and chromatin condensed nuclei. In addition, H 2 O 2 induced p53 nuclear translocation, up-regulated Bax and down-regulated Bcl-2 expression thereby increased Bax/Bcl-2 ratio. These toxic effects of H 2 O 2 were reversed by 100 µM EGCG pretreatment. These studies suggest that EGCG protects H 2 O 2 -induced cell death in ARPE-19 cells by its antioxidant property and attenuation of p53 nuclear translocation.