测试一个化三甲基旋探针的评估,用于以R2 为基础的EPR氧度成像,以增强动态范围
Shun Kishimoto1,2, Nallathamby Devasahayam1, Gadisetti V R Chandramouli3
1Radiation Biology Branch, Center for Cancer Research, NCI, Bethesda, Maryland, USA.
Magnetic resonance in medicine
|September 7, 2023
概括
Ox071是一种三甲基 (TAM) 旋转探头,由于其增强的灵敏度和更广泛的氧气 (pO2) 部分压力动态范围,它在使用电子磁共振 (EPR) 氧度测量组织氧气水平时,比Ox063表现出更高的性能.
科学领域:
- 生物医学工程 生物医学工程
- 医学物理 医学物理
- 化学 化学 化学
背景情况:
- 组织氧气水平 (pO2) 是细胞功能和疾病的关键指标.
- 电子偏磁共振 (EPR) 氧计为测量pO2.2提供了一种非侵入性的方法.
- 三甲基 (TAM) 旋转探针用于EPR氧度,但它们的比较有效性需要评估.
研究的目的:
- 为了比较两个TAM旋转探头Ox071和Ox063的有效性,用于测量组织氧气水平.
- 在低氧和正常氧条件下使用基于R2*的EPR氧计来评估探头的性能.
主要方法:
- 校准R2*依赖于自旋探头度和氧气水平 (0-21%O2) 的依赖性.
- 在低氧条件下的小鼠瘤异种移植 (MIA PaCa-2) 的体内EPR氧度.
- 在正常条件下对健康小鼠脏进行体内EPR氧测.
- 使用单点成像和多梯度技术进行3D图像重建,以确定R2*地图.
主要成果:
- 在测试的pO2范围内,Ox071的信号强度大约是Ox063的三倍.
- 瘤pO2组图显示了两个探针的偏,Ox071捕获了更高的pO2计数 (>32 mm Hg).
- 在正常性脏中,Ox071清楚地划分了高p O2皮质和低p O2髓,达到高达55 mm Hg,而Ox063成像错过了这些更高的范围.
结论:
- 与Ox063相比,Ox071表现出更高的灵敏度和更广泛的pO2动态范围.
- Ox071是一种更有效的氧度探针,用于在低氧和正常氧环境中表征组织氧化.
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