EFFECTS OF GAMMA-IRRADIATION ON CELLS AND THEIR CONSTITUENTS

伽马射线对细胞及其成分的影响

• 批准号: 3939522
• 负责人: P RIESZ
• 金额: --
• 依托单位: DIVISION OF CANCER TREATMENT
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/3939522
• 关键词: DNA; antineoplastics; cytotoxicity; electron spin resonance spectroscopy; free radicals; gamma radiation; ionizing radiation; light adverse effect; neoplasm /cancer photoradiation therapy; neoplasm /cancer thermotherapy; nonvisual photosensitivity; phthalocyanin; radiobiology; radiopharmacology; radiosensitizer; tissue /cell culture; ultraviolet radiation

Certain water soluble sulfonated phthalocyanines are efficient photosensitizers for killing mammalian cells are appear to be promising candidates for replacing hematoporphyrin derivative in photodynamic therapy (PDT) of human tumors. The post- illumination photohemolysis of human red blood cells was used as a model system for studying membrane damage sensitized by various sulfonated phthalocyanines. Scavenger studies with tryptophan (which reacts rapidly with singlet oxygen) and mannitol (which reacts rapidly with hydroxyl radicals but not with singlet oxygen) are consistent with the predominant role of singlet oxygen in the photohemolysis sensitized by sulfonated aluminum phthalocyanine. Similar results have been obtained in preliminary experiments for the photosensitized cell killing of V- 79 Chinese hamster cells. The chemical effect of ultrasound are being investigated in relation to hyperthermia (used in combination with radiation therapy) and the possible effects of diagnostic and therapeutic applications. In the process of transient cavitation, the collapsing cavitation bubbles result in very high temperatures (greater than 5000 degrees C) and pressures which lead to the dissociation of water to hydrogen atoms and hydroxyl radicals. For solutions containing volatile compounds such as alcohols, the reaction products are those typical of combustion processes (in the collapsing bubbles) and those similar to the effects of ionizing radiation due to the hydrogen atoms and hydroxyl radicals which escape into the bulk of the solution to react with solute molecules. In the case of methanol, methyl radicals formed by the high temperature dissociation of the carbon-oxygen bond, as well as radicals formed by the reactions of hydrogen atoms and hydroxyl radicals with methanol were detected by spin trapping and electron spin resonance. The radicals produced in the sonochemistry of nucleic acid bases, nucleosides, amino acids and peptides have been identified by spin trapping.

某些水溶性磺化酞菁是有效的 用于杀死哺乳动物细胞的光敏剂似乎 替代血卟啉衍生物的有希望的候选物 光动力疗法（PDT）的应用。 邮报- 人红细胞的光照光溶血被用作 一个研究致敏膜损伤的模型系统， 各种磺化酞菁。 清除剂研究， 色氨酸（与单线态氧快速反应）， 甘露醇（其与羟基自由基快速反应，但不 与单线态氧）的主要作用一致， 单重态氧在磺化敏化光溶血中的作用 酞菁铝 类似的结果已经在 初步实验的光敏细胞杀伤V- 79个中国仓鼠细胞。 超声波的化学效应是 正在研究与高温有关的问题（用于 联合放射治疗）以及 诊断和治疗应用。 过程中 瞬时空化，破裂的空化气泡导致 非常高的温度（大于5000摄氏度）， 导致水分解成氢的压力 原子和羟基。 对于含有挥发性物质的溶液 化合物如醇，反应产物是那些 典型的燃烧过程（在破裂的气泡中）， 这些类似于电离辐射的影响， 氢原子和羟基自由基， 与溶质分子反应。 的情况下 甲醇，甲基自由基形成的高温 碳-氧键的解离，以及自由基 由氢原子和羟基反应形成 通过自旋捕获和电子自旋检测甲醇 共振 声化学中产生的自由基 核酸碱基、核苷、氨基酸和肽具有 通过自旋捕获来识别。