Sun Li-xia, Yao Ke, Jiang Huai, He Ji-liang, Lu De-qiang, Wang Kai-jun, Li Hong-wu
Eye Center of the Second Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou 310009, China.
Zhonghua Yan Ke Za Zhi. 2006 Dec;42(12):1084-8.
To investigate the effects of acute exposure of low-power 217 Hz modulated 1. 8 GHz microwave radiation on the DNA damage of human lens epithelial cells (hLECs) and repair.
Cultured hLECs were exposed to 217 Hz modulated 1. 8 GHz microwave radiation at SAR (specific absorption rate) of 1. 0, 2. 0, 3. O0 and 4. 0 W/kg for 2 hours in an sXc-1800 incubator and irradiate system, the DNA single strand breaks were detected with comet assay ( single-cell gel electrophoresis) in sham-irradiated cells and irradiated cells incubated for varying periods: 0, 30 and 60 minutes after irradiation. Images of comets were digitized and analyzed using an Imagine-pro plus software, and the indexes used in this study were tail length (TL) and tail moment (TM). BrdU was added into the medium with additional one hour incubation after radiation, the cell proliferation rate was determined using a BrdU-kit.
The difference of DNA-breaks between the exposure and sham exposure groups induced by 1.0 and 2.0 W/kg irradiation were not significant in each time points (P > 0.05) ; there were significant difference in both groups at the exposure dose of 3. 0 and 4. 0 W/kg immediately and at the time of 30 minutes after irradiation (P <0. 01) ; if the radiation exposure time was beyond one hour no differences were be able to detected in 3.0 W/kg group (P > 0. 05) compared with control, but the evidence of significant DNA damage still existed in 4. 0 W/kg group at the same time point. Cell proliferation rate had no significant difference when the application of SAR was < or = 3. 0 W/kg (P >0. 05) , however the cell proliferation was decreased significantly at the dose of 4. 0 W/kg irradiation ( P < 0. 01).
No effective DNA damage was induced using comet assay after 2 hours irradiation of 1. 8 GHz microwave on hLECs at the dose SAR < or = 3.0 W/kg. 4.0 W/kg irradiation caused significantly DNA damage and inhibition of hLECs proliferation.
探讨低功率217Hz调制的1.8GHz微波辐射急性暴露对人晶状体上皮细胞（hLECs）DNA损伤及修复的影响。
将培养的hLECs置于sXc - 1800培养箱和辐照系统中，分别以比吸收率（SAR）为1.0、2.0、3.0和4.0W/kg暴露于217Hz调制的1.8GHz微波辐射2小时，对假照射细胞和照射后分别孵育0、30和60分钟的照射细胞，采用彗星试验（单细胞凝胶电泳）检测DNA单链断裂情况。用Imagine - pro plus软件对彗星图像进行数字化处理和分析，本研究采用的指标为尾长（TL）和尾矩（TM）。辐射后在培养基中加入BrdU并额外孵育1小时，用BrdU试剂盒测定细胞增殖率。
1.0和2.0W/kg照射的暴露组与假暴露组在各时间点的DNA断裂差异无统计学意义（P>0.05）；3.0和4.0W/kg暴露剂量在照射即刻及照射后30分钟时两组差异有统计学意义（P<0.01）；3.0W/kg组辐射暴露时间超过1小时后与对照组相比差异无统计学意义（P>0.05），但4.0W/kg组在同一时间点仍存在明显的DNA损伤证据。当SAR≤3.0W/kg时细胞增殖率差异无统计学意义（P>0.05），然而4.0W/kg照射剂量时细胞增殖显著降低（P<0.01）。
1.8GHz微波以SAR≤3.0W/kg剂量照射hLECs 2小时后，彗星试验未诱导有效的DNA损伤。4.0W/kg照射导致明显的DNA损伤并抑制hLECs增殖。
