The z-spectrum from human blood at 7T.
The z-spectrum from human blood at 7T.
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DOI：
10.1016/j.neuroimage.2017.10.053
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发表时间：
2018-02-15
期刊：
影响因子：
5.7
通讯作者：
Gowland PA
中科院分区：
文献类型：
--
作者：
Shah SM;Mougin OE;Carradus AJ;Geades N;Dury R;Morley W;Gowland PA
化学交换饱和转移(CEST)已被用来评估动物和人类的健康和病理组织。然而，来自血液的CEST信号还没有得到充分的评估。本文介绍了通过z谱分析在人体血液中检测到的CEST和核Overhauser增强(NOE)信号。我们评估了血氧水平、红细胞压积、细胞结构和pH对7T下不同饱和功率的体外人血中z谱的影响。用洛伦兹差(LD)模型拟合和AREX(补偿T1变化)对数据进行了分析，这两种方法已成功地用于研究CEST的体内效应。还进行了完整的Bloch-McConnell拟合，以提供各种池的汇率和横向松弛速率的初步估计。在3.5ppm、−1.7ppm和−3.5ppm处观察到CEST和NOE信号，发现它们主要来自红细胞(RBC)，尽管存在酰胺质子转移(APT)CEST效应，NOE与氧合水平无关。裂解后，APT和NOE信号显著下降。血液中不同的pH水平导致了APT和NOE的变化(−为3.5ppm)，这表明这种NOE信号在一定程度上是一个交换传递过程。这些结果将对在体Z谱的评估具有重要意义。
Chemical Exchange Saturation Transfer (CEST) has been used to assess healthy and pathological tissue in both animals and humans. However, the CEST signal from blood has not been fully assessed. This paper presents the CEST and nuclear Overhauser enhancement (NOE) signals detected in human blood measured via z-spectrum analysis. We assessed the effects of blood oxygenation levels, haematocrit, cell structure and pH upon the z-spectrum in ex vivo human blood for different saturation powers at 7T. The data were analysed using Lorentzian difference (LD) model fitting and AREX (to compensate for changes in T1), which have been successfully used to study CEST effects in vivo. Full Bloch-McConnell fitting was also performed to provide an initial estimate of exchange rates and transverse relaxation rates of the various pools. CEST and NOE signals were observed at 3.5 ppm, −1.7 ppm and −3.5 ppm and were found to originate primarily from the red blood cells (RBCs), although the amide proton transfer (APT) CEST effect, and NOEs showed no dependence upon oxygenation levels. Upon lysing, the APT and NOE signals fell significantly. Different pH levels in blood resulted in changes in both the APT and NOE (at −3.5 ppm), which suggests that this NOE signal is in part an exchange relayed process. These results will be important for assessing in vivo z-spectra.
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来自Z频谱拟合的2ppm（CEST@2ppm）处的CEST信号与脑肿瘤中的肌酸分布相关。
影响因子：
2.9
作者：
Cai, Kejia;Singh, Anup;Poptani, Harish;Li, Weiguo;Yang, Shaolin;Lu, Yang;Hariharan, Hari;Zhou, Xiaohong J.;Reddy, Ravinder
通讯作者：
Reddy, Ravinder
影响因子：
3.3
作者：
Jones, Craig K.;Polders, Daniel;Hua, Jun;Zhu, He;Hoogduin, Hans J.;Zhou, Jinyuan;Luijten, Peter;van Zijl, Peter C. M.
通讯作者：
van Zijl, Peter C. M.
影响因子：
2.2
作者：
Ward, KM;Aletras, AH;Balaban, RS
通讯作者：
Balaban, RS
影响因子：
3.3
作者：
GASPAROVIC, C;MATWIYOFF, NA
通讯作者：
MATWIYOFF, NA
影响因子：
3.3
作者：
Ma, Yuhan;Berman, Avery J. L.;Pike, G. Bruce
通讯作者：
Pike, G. Bruce