Biomedical subjects

Yoon Jung Lee

Publications and source records attributed to Yoon Jung Lee.

3 recordsLinked to original sources

PubMed2006

Conjunctival changes induced by LASIK suction ring in a rabbit model.

PURPOSE: To study histopathological changes in rabbit conjunctiva after suction ring application. METHODS: A suction ring was applied to adult albino rabbit eyes (n = 30) with a vacuum pressure of 508 mm Hg for 40 s. Three rabbits were sacrificed at 3 h (3-hour group), 6 h (6-hour group), 1 day (1-day group), 3 days (3-day group), and 7 days (7-day group) after the suction ring application. Histopathological examinations included hematoxylin and eosin, Alcian blue pH 2.5-periodic acid-Schiff (AB2.5-PAS), and Alcian blue pH 1.0-periodic acid-Schiff (AB1.0-PAS) staining. TdT-dUTP-terminal nick-end labeling (TUNEL) assay and immunohistochemical staining for p65 were also performed. RESULTS: The site of suction ring application and adjacent areas did not show transient inflammation. AB2.5-PAS staining revealed that the percentage of neutral mucin was significantly different between 54.5 +/- 1.6% in the control group and 22.3 +/- 1.3% in the 7-day group (p = 0.04). Apoptosis occurred not only at the site of suction ring application, but also in adjacent regions. At all time points, conjunctival epithelium showed no positive staining for p65. CONCLUSION: The transient elevation of pressure induced by a suction ring is sufficient to cause conjunctival damage. These histological results support the finding that conjunctival damage caused by suction ring application is one of many etiologies of dry eye syndrome following laser in situ keratomileusis.

Alcian Blue↗

PubMed2006

Ocular hypertensive response to topical dexamethasone ointment in children.

PURPOSE: To investigate the rate and the degree of the ocular hypertensive response to dexamethasone ointment in children undergoing eyelid surgery. METHODS: Dexamethasone ointment (Dexcosil) was applied three times a day for the first week and twice a day for the second to third week postoperatively to children undergoing epiblepharon surgery. Intraocular pressure (lOP) was measured on the day before surgery, postoperative day 1, 7, 14, 21, 28 and 2 weeks thereafter until the IOP reached preoperative levels. Peak IOP, IOP net increase and time to reach a peak IOP were analyzed. Dexamethasone ointment was discontinued if the IOP was 25 mmHg or more. RESULTS: A total of 96 children (mean age, 6.5 +/- 2.7 years) were included. Preoperative mean IOP was 13.6 +/- 2.9 mmHg (range 7-19). After dexamethasone ointment treatment, the children showed a significant rise in IOP as compared with the preoperative values. The peak IOP was 20.6 +/- 4.9 mmHg (range 11-39) and the time to reach peak IOP was 8.5 +/- 5.9 days. The low responders (delta IOP < or = 5 mmHg) of our group comprised 35.4% (34/96) of patients, intermediate responders (delta IOP 6-15 mmHg) comprised 56.3% (54/96) of patients and high responders (delta IOP > or =16) comprised 8.3% (8/96) of patients. A net increase in IOP was significantly higher in children 5 years old or less as compared with those older than 5 years (age < or =5, 9.4 +/- 7.5 mmHg vs. age > 5, 6.3 +/- 4.4 mmHg; p = 0.015, unpaired t-test). CONCLUSIONS: Ocular hypertensive response after dexamethasone ointment to the eyelids occurred frequently in children, especially those 5 years old or younger.

Administration, Topical↗

PubMed2003

[The effects of tamoxifen on human hepatocellular carcinoma cell proliferation and transforming growth factor-beta1 expression].

BACKGROUND/AIMS: Tamoxifen has been tried in patients with hepatocellular carcinoma (HCC), however, its inhibitory mechanism remains unknown. In this study, we evaluated the effects of tamoxifen on HCC cell growth and the expression of transforming growth factor-beta1 (TGF-beta1) which had been known as an important cytokine in growth of HCC. METHODS: Hep 3B cells were cultivated in estrogen free media with 0.1 micro M, 0.5 micro M, 1 micro M, 5 micro M, and 10 micro M of tamoxifen for 6 days. Viable cells were counted daily and the TGF-beta1 concentrations in supernatant were measured by ELISA method. RESULTS: The number of viable HCC cells increased rather significantly after the treatment of tamoxifen of lower concentration (0.1micro M) compared with that of the control (2.59x10(7) vs. 1.97x107; p<0.05). As the concentration of treated tamoxifen was higher, the number of viable HCC cells became gradually less, resulting in the significant decrease of it at the highest concentration (10micro M) compared with that of the control (1.40x10(7) vs. 1.97x10(7); p<0.05). TGF-beta1 concentration in supernatant of tamoxifen-treated samples was significantly decreased compared with those of controls, regardless of the amount of treated tamoxifen. CONCLUSIONS: These results suggest that tamoxifen may suppress TGF-beta1 expression to an extent, although it has different effects on the proliferation of HCC cells, at the various concentrations of this agent in vitro. Such effects of tamoxifen on TGF-beta1 expression may inhibit the growth and progression of HCCs over-expressing TGF-beta1 in vivo.

Antineoplastic Agents, Hormonal↗