评估胺分子起源的质子转移加权成像
Casey Sun1,2, Yu Zhao1,3,4, Zhongliang Zu1,3,5
1Vanderbilt University Institute of Imaging Science, Vanderbilt University Medical Center, Nashville, Tennessee, USA.
Magnetic resonance in medicine
|September 26, 2023
概括
胺基质子转移加权 (APTw) 成像信号受到蛋白质和脂质的影响. 高和幅度揭示了蛋白质贡献,而低幅度则通过中继核Overhauser增强 (rNOE) 突出显示了脂质效应.
科学领域:
- 生物医学成像技术 生物医学成像技术
- 磁共振成像技术 磁共振成像技术
- 化学交换和转移 (CEST) 是一种
背景情况:
- 胺质子转移加权 (APTw) 成像被认为主要反映移动蛋白和.
- 这种假设依赖于胺质子转移 (APT) 效应在其他化学交换和转移 (CEST) 效应上占主导地位,例如来自氨基胺/瓜尼丁的效应,以及中继核Overhauser增强 (rNOE).
研究的目的:
- 评估假设APT效应在APTw成像中占主导地位的有效性.
- 为了区分APT,氨基/瓜尼丁CEST和rNOE对APTw信号的贡献.
- 研究生物组织中APTw信号的分子起源.
主要方法:
- 开发和应用两种辅助不对称分析指标,以改变氨/ CEST 和其他影响的贡献.
- 辅助指标与常规不对称分析对健康的老鼠大脑进行比较,以评估氨酸/瓜尼丁的贡献.
- 对透析的组织同质物和超级物进行分析,以分离宏分子,小代谢物和脂质的贡献.
主要成果:
- 在高和幅度 (2-3μT) 的正APTw信号表明氨基/瓜尼丁的显著贡献.
- 来自透析同质物的APTw信号的微不足道变化表明大分子,而不是小代谢物,是主要来源.
- 组织同质体中低和幅度 (1μT) 的负APTw信号,与超级生物中的正信号相比,表明脂质有负的贡献,蛋白质有积极的贡献.
结论:
- 在高和幅度的积极APTw信号受到可溶性蛋白质通过CEST的显著影响,包括胺基,氨基和瓜尼丁质子转移.
- 在低和幅度的负APTw信号主要是由脂质通过rNOE贡献的.
- APTw信号的起源是复杂的,由蛋白质转移效应和脂质rNOE的贡献,取决于和幅度.
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