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Aim: To investigate the effects of curcumin (Cur) nanoparticles loaded with chitosan derivatives grafted by deoxycholic acid (Chit-DC) on human retinal pigment epithelial (hRPE) cell proliferation and vascular endothelial growth factor (VEGF) mRNA expression., Methods: Cur nanoparticles were synthesized with Chit-DC as the carrier and Cur as the supported drug. Cell counting kit-8 (CCK-8) method was used to detect the effects of different concentrations of Cur/Chit-DC, Chit-DC, and Cur on the proliferation of hRPE cells for different times. The changes of Cur/Chit-DC and Cur on hRPE cell cycle were determined by flow cytometry. Semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR) was used to detect the mRNA expression levels of VEGF in hRPE cells treated with Cur, Chit-DC and Cur/Chit-DC at 10 µg/mL for 24h., Results: Different concentrations of Chit-DC nanoparticle treated hRPE cells had no significant difference in terms of optical density (OD) values compared with the control group at 24h and 48h. Moreover, there was no change in the cell morphology under a light microscope. After 24h treatment with Cur/Chit-DC and Cur, the percentage of G0-G1 phase cells increased and the percentage of S phase cells decreased in all concentration groups. Cur/Chit-DC and Cur in all concentration groups inhibited the proliferation of hRPE cells in a time and dose dependent manner, and reduced the expression level of VEGF mRNA., Conclusion: The Cur/Chit-DC nanoparticles can release Cur continuously and have sustained release function. Both Cur/Chit-DC nanoparticles and Cur could inhibit hRPE cells cultured in vitro , and could reduce the expression level of VEGF mRNA in hRPE cells., (International Journal of Ophthalmology Press.)

Toilet hygiene is an important preventive measure for infectious diseases, including severe acute respiratory syndrome (SARS) and COVID-19. This study explored public's opinions on improving toilet environment and hygiene practices in Hong Kong. A mixed-method approach was applied. We conducted 4 focus groups plus 3 individual interviews among the Hong Kong Chinese, followed by a questionnaire survey with 300 respondents recruited from various districts. Difference in response distributions between groups with different demographics was tested by Pearson χ 2 test. Instead of advocating for advanced toilet facilities, respondents were mostly concerned about basic hygiene issues. Malfunctioning facilities resulting from poor toilet management, such as clogged toilets, stained facilities, and problematic flushing systems, were most cited as barriers to toilet hygiene practices. Three quarters of the survey respondents expressed concerns over worn and poorly maintained toilets, shortage of janitors, and cleansing supplies. However, respondents who were older ( P < .001), less educated ( P < .001), and had lower income ( P = .001) were significantly more likely to find hygiene conditions in public toilets satisfactory. The findings reflected the substandard of the current provisions as a developed city in Asia. Enhanced efforts by the government to maintain basic toilet supplies and facilities is the key to improving public compliance to toilet hygiene practices.