Topical cell-free conditioned media harvested from adipose tissue-derived stem cells promote recovery from corneal epithelial defects caused by chemical burns.

Corneal chemical burns can lead to blindness following serious complications. As most of these complications are caused by failure of reepithelization during the acute phase, treatment at this stage is critical. Although there have been some studies on corneal injury recovery using adipose tissue-derived stem cells (ADSCs), none has reported the effect of topical cell-free conditioned culture media (CM) derived from ADSCs on corneal epithelial regeneration. Here, the best conditions for CM were selected and used for in vitro and in vivo experiments. Corneal burn in rats was induced using 100% alcohol. The chosen CM was administered to corneal burn rats (CM-treated [CT] group) four times a day for three days and this group was compared with the normal control and corneal burn (CB) groups. Biomicroscopic fluorescence images and the actual physical corneas were taken over time and used for analysis. mRNA levels of hepatocyte growth factor and epidermal growth factor (EGF) were significantly increased, whereas those of vascular endothelial growth factor, interleukin (IL)-1ß, IL-6, IL-10, and matrix metalloproteinase-9 were significantly decreased in the CT group compared with those in the CB group. The numbers of proliferating cell nuclear antigen- and zonular occludens-1-positive cells in the CT group were significantly higher than those in the CB group. The macrophage-infiltrating corneas in the CT group expressed significantly more of the M2 marker arginase than corneas in the CB group. Optimal CM (× 0.5 concentration) treatment significantly accelerated the migration of corneal epithelial cells and induced upregulation of the expression of IL-6, EGF, and C-X-C chemokine receptor type 4 mRNAs. Overall, in this study, topical administration of cell-free CM promoted regeneration of the corneal epithelium after induction of chemical burns.

Time Series Changes in Cataract Surgery in Korea.

PURPOSE: We analyzed time series changes in cataract surgeries in Korea, and provide basic data to enhance the efficiency of medical services for cataract surgery. METHODS: Among cataract surgery statistics registered in the Korean National Health Insurance Cooperation from 2006 to 2012, we used data regarding the number of patients and operations and the number of patients and operations per 100,000 people. We analyzed various time series changes, including differences by sex and age. RESULTS: The total numbers of patients from 2006 to 2012 by year were 207,370; 228,170; 250,289; 268,548; 289,867; 308,111; and 302,182, respectively. The total numbers of operations from 2006 to 2012 by year were 272,920; 305,807; 338,332; 365,874; 398,338; 428,158; and 420,905, respectively. The number of patients and operations per 100,000 people were highest in men 80 to 84 years old and women 75 to 79 years old. Comparing the number of operations in 2006 and after, the patient age group with the highest increase rate changed from over 85 years old to 75-79 years old since 2010 in men and from over 85 years old to 50-54 years old since 2009 in women. For each year investigated, the number of operations performed was higher than the number of patients who received operations. CONCLUSIONS: Over the study period, the number of cataract surgeries increased, while the age of cataract patients decreased. Additionally, the number of cataract-related surgeries increased in relation to the number of patients.