Incidence, Timing of Screening Examinations and Perinatal Risk Factors for Retinopathy of Prematurity in Very Low Birth Weight Infants / 대한주산의학회잡지

OBJECTIVE: This study was conducted to evaluate the incidence, the optimal timing of screening examinations for retinopathy of prematurity(ROP) and to analyze perinatal risk factors associated with cryotherapy or lasertherapy(CT/LT) in ROP. METHODS: Medical records of 130 very low birth weight(VLBW) infants who admitted to the NICU of Wonkwang University Hospital from July 1997 to June 2002 were reviewed retrospectively. We evaluated the incidence and severity of ROP by gestational age(GA) and birth weight(BW). And the comparisons of perinatal risk factors between ROP with and without CT/LT have been made. RESULTS: Incidence of ROP was 36.9% and mean GA and BW were 29.1+/-1.99 weeks, 1,153+/-209 gm in VLBW infants respectively. ROP Stage II or greater was 15.4% of VLBW infants, 41.7% of ROP infants, and 27.1% of ROP infants were treated with CT/LT. All infants with BW <750gm or GA <26 weeks were developed ROP with stage II or greater and treated with CT/LT. First detection of ROP was performed at chronologic age(CA) 3 weeks, postconceptional age(PCA) 30 weeks, and first identification of threshold ROP needed with CT/LT were at CA 5 weeks and PCA 33 weeks. The perinatal risk factors with CT/LT for ROP were significant in GA, BW, Apgar score at 1 and 5 minutes and number of blood transfusion. The mean time of spontaneous regression is 13.4+/-8.8 weeks in the mild ROP infants without CT/LT. CONCLUSION: The incidence of ROP is 36.9% and the optimal timing of screening for ROP should be selected by earlier time in 2 guidelines of at 5 weeks of CA and 33 weeks of PCA in VLBW infants. And the related risk factors with CT/LT for threshold ROP were GA, BW and Apgar score at 1 and 5 minutes and number of blood transfusions.

Cytotoxicity of Diamide and the Protective Effect of Thioredoxin on Diamide-Induced Vasculotoxicity in Vascular Endothelial Cells

BACKGROUND AND OBJECTIVES: This study was designed to examine the effects of diamide and thioredoxin (TRX) on vascular endothelial cells in order to clarify the mechanism by which vascular damage is mediated by oxygen free radicals. MATERIALS AND METHODS: The pulmonary artery endothelial cell (PAEC) line derived from bovine serum was cultured for 8 hours in media supplemented with various concentrations of diamide and TRX. The XTT assay, MTS assay, SRB assay, LDH activity and lipid peroxidation tests were perfomed. RESULTS: In XTT and MTS assays, diamide significantly decreased the cell viability of cultured PAEC in a dose- and time-dependent manner. Diamide showed a decrease in the amount of total protein, although it showed an increase of lipid peroxidation and LDH activity in cultured PAEC. In regards to the protective effect of TRX on diamide-induced cytotoxicity, this showed an increase of total protein, however it showed a decrease of lipid peroxidation and LDH activity. CONCLUSION: Our results suggest that diamide has a vasculotoxic effect on cultured bovine PAEC and that TRX is very effective in the protection of diamide-induced cytotoxicity by duye to the increase of total protein and the decrease of lipid peroxidation and LDH activity in these cultures.