The human eyelid adipose-derived stem cells (HEACs) are known as a candidate source for stem cell-based therapy. HEACs possess the ability to proliferate in vitro and multipotency to differentiate into adipogenic, osteogenic and chondrogenic cells. To be used later than the time of collection, a long-term storage is needed. In this study, we investigated stem cell characteristics after cryopreservation of HEACs for 6 months and 1 year in liquid nitrogen. Frozen-thawed stem cells have shown that cumulative cell and doubling numbers were similar to those of fresh HEACs. After thawing, HEACs expressed stem cell-related genes of SCF, NANOG, OCT4, and TERT, ectoderm-related genes of NCAM and FGF5, mesoderm/endoderm-related genes of CK18 and VIM. They also consistently expressed transcripts of the immune-related genes of HLA-ABC and β2M. To induce mesodermal differentiation, cell were cultivated in adipogenic, osteogenic or chondrogenic medium for 2～3 weeks. After each differentiation culture, HEACs expressed adipocyte-, osteocyte- and chondrocytespecific genes. They were also stained with Oil red O, von Kossa, or alcian blue, revealing adipogenic, osteogenic, or chondrogenic character, respectively. The results suggest that long-term storage up to 1 year do not affect their biological properties, HEACs may be suitable for clinical application on cell-based therapies.

This paper aims to describe the characteristics of air pollution using air pollutants concentration and meteorological data observed at Kimhae from December, 1996 to November, 1997. The results are as follows : The concentration distribution of sulfur dioxide(SO2), carbon monoxide(CO), particulate matter(PM-10), and nitrogen dioxide(NO2) is high during the late fall and winter and low during the summer, but ozone concentration is low during the winter season and high during summer season except Jangma period and these distributions appear to be closely connected with insolation and the number of clear day. Diurnal variation of concentrations for sulfur dioxide, particulate matter, and carbon monoxide are high during the rush hours and nighttime and low during the daytime and these variations are distinct toward the winter season. And diurnal variation of nitrogen dioxide concentration has also same pattern and these patterns are closely related to the increasing traffic volume at rush hours. Diurnal variation of ozone concentration is generally increase for daytime and decrease for the late afternoon and are closely related to the insolation and photochemical reaction. The 24 hour average concentrations of air pollutant observed at Kimhae represented a positive correlation and a negative correlation for O3 and also a negative correlation for the meteorological elements such as wind speed and cloud cover.