Effect of vascular endothelial growth factor small interfering RNA (siRNA) on retinal microvascular endothelial cells under hypoxia condition in vitro / 中华儿科杂志

<p><b>OBJECTIVE</b>To explore VEGF siRNA's effect on the immature fetal retinal microvascular endothelial cells in vitro.</p><p><b>METHOD</b>The fresh retinal micrangium was primarily cultured to obtain microvascular endothelial cells. CoCl2 was used to simulate oxygen-deficient conditions. siRNA directed against human VEGF was designed and chemically synthesized. There were 3 groups in our experiment: VEGF siRNA group, hypoxia control group, and negative siRNA control group. The fetal retinal micrangium vascular endothelial cells were transfected by using liposome. The expression levels of VEGF mRNA and protein were evaluated by RT-PCR and Western blotting 24, 48, 72 h after transfection, cell proliferation was evaluated by MTT method.</p><p><b>RESULT</b>The expression levels of VEGF mRNA decreased by 21.05%, 79.67%, and 90.48% 24 h, 48 h, and 72 h after transfection as compared to those in hypoxia control group, the expression level of VEGF protein had decreased by 14.58%, 66.97%, and 81.61% as compared to those in hypoxia control group. The siRNA could decrease cell proliferation under hypoxia too, the multiplication rate after 12, 24, 48, and 72 h decreased by 15.0%, 42.9%, 78.3% and 65.9%.</p><p><b>CONCLUSION</b>VEGF siRNA could down-regulate the expression of VEGF in immature fetal retinal microvascular endothelial cells and suppressed cell proliferation. Application of siRNA to inhibit expression of VEGF may be a hopeful way to prevent and cure ROP.</p>

Study on the changes of incidence rates on birth defects through hospital based surveillance program in Guangdong province during 1997-2007 / 中华流行病学杂志

Objective To analyze the tendency of hospital based surveillance incidence rates of birth defects in Guangdong province to provide reference evidence for related intervention program. Methods Data from hospital based birth defects surveillance of Guangdong province during 1997-2007 were analyzed retrospectively. Results The overall surveillance rates of birth defects in Guangdong province showed an increasing trend form 98.9 per 10 000 birth in 1997 to 244.2 per 10 000 birth in 2007. Among the frequently seen birth defects, the rate of congenital heart diseases increased sharply, but the rates of congenital talipes equinovarus, polydactyly, cleft lip with/without cleft palate showed a slight increasing trend.It seemed that there was a significant difference between different maternal age interval and gender of the infants. Mother's illness, drug use, and exposure to environment harmful factors in early pregnancy stage, high maternal age, negative bearing history were the suspect risk factors for birth defects. Conclusion The increasing trend of surveillance rate of birth defects seemed to be comprehensively affected by the factors as: method being adopted, target and extension of birth defects surveillance, technology used for diagnosis, kinds of risk factor,and quality control on surveillance programs.