Speck W T, Chen C C, Rosenkranz H S
Pediatr Res. 1975 Mar;9(3):150-3. doi: 10.1203/00006450-197503000-00009.
The widespread use of phototherapy for neonatal hyperbilirubinemia has caused some concern since substances other than bilirubin may be photoactivated. The toxic properties of these photoactivated substances might prove to be more harmful to the neonatal infant than bilirubin. The purpose of the present study was to investigate the effect of photoactivated riboflavin in low concentration, on purified DNA. The results demonstrate extensive changes in the structure of DNA (see Table 1) manifested by (1) a change in the peak absorbance in the ultraviolet, (2) a decrease in the temperature of the thermal helix-coil transition, (3) a slight decrease in the sedimentation coefficient, and (4) an increase in the buoyant density values (1.704-1.709). These observations are consistent with the interpretation that there has been an alteration of one of the base moieties with minimal cleavage of the phosphodiester linkages. Results with human cells in tissue culture indicate that a similar photodynamic effect of riboflavin on the DNA occurs in living cells.
由于除胆红素外的其他物质可能被光激活，光疗在新生儿高胆红素血症中的广泛应用引起了一些关注。这些光激活物质的毒性特性可能被证明对新生儿比胆红素更有害。本研究的目的是研究低浓度光激活核黄素对纯化DNA的影响。结果表明DNA结构发生了广泛变化（见表1），表现为：（1）紫外线吸收峰的变化；（2）热螺旋-卷曲转变温度降低；（3）沉降系数略有降低；（4）浮力密度值增加（1.704 - 1.709）。这些观察结果与以下解释一致，即碱基部分之一发生了改变，而磷酸二酯键的断裂最少。组织培养中的人体细胞结果表明，核黄素对DNA的类似光动力作用也发生在活细胞中。
