Intermolecular Multiple-Quantum Coherence Effects in NMR

描述（由申请人提供）：本提案要求继续 资助分子间多量子相干（iMQCs）的应用 在核磁共振光谱（NMR）中，体内磁共振 磁共振成像（MRI）和磁共振波谱（MRS）。iMQCs，对应于 在溶液中分离的分子上同时自旋翻转（分离 10 μ m-10 mm是典型的），根据常规的 核磁共振的理论框架;然而，在过去的几年里，沃伦博士 实验产生的iMQCs的信号几乎与传统的一样大， 磁化，从理论上描述了这种复杂的现象，并开发了 有用的应用。例如，沃伦博士已经证明，iMQC成像提供了 大鼠脑肿瘤增强和人脑成像中的新型对比剂 （包括功能激活），在低磁场下具有可接受的灵敏度 1.5特斯拉其他演示的应用包括消除 不均匀加宽而不去除化学位移差异， 空间定位MRS（无磁化率展宽和匀场 伪影限制了该技术在肿瘤中的当前应用 检测和分级），以及溶质之间的异相磁化传递 和溶剂峰。 下一个资助期的临床应用包括改进iMQC 成像方法（对比度优化，引入流量补偿， 预饱和），功能性MRI研究的新3特斯拉MRI在普林斯顿大学， 验证BOLD机制并确定子体素激活结构， 空间定位的体内iMQC成像的各种应用。沃伦医生 建议使用现有的高分辨率1066 MHz NMR对大分子进行分析， 产生不均匀磁场的磁体（并通过 iMQCs），以确定蛋白质的核磁共振场的潜在价值 问题研究沃伦博士还建议将他的工作扩展到检测 磁化波动与偶极场，这可能会演变成另一个 独特的成像对比机制，可以完全改变 在NMR中检测到低γ或低浓度物质。

DESCRIPTION (provided by applicant): This proposal requests continuation funding for applications of intermolecular multiple-quantum coherences (iMQCs) in nuclear magnetic resonance spectroscopy (NMR), in vivo magnetic resonance imaging (MRI) and magnetic resonance spectroscopy(MRS). iMQCs, which correspond to simultaneous spin flips on separated molecules in solution (separations of 10 um-l0 mm are typical), should be unobservable according to the conventional theoretical framework of NMR; yet over the last few years, Dr. Warren has experimentally generated iMQCs with signals nearly as large as the conventional magnetization, theoretically described this complex phenomenon, and developed useful applications. For example, Dr. Warren has shown that iMQC imaging gives tumor enhancement in rat brains and novel contrast in human brain imaging (including functional activation), with acceptable sensitivity at fields as low at 1.5 Tesla. Other demonstrated applications include elimination of inhomogeneous broadening without removal of chemical shift differences, spatially localized MRS (without susceptibility broadening and shimming artifacts which limit current applications of this technique for tumor detection and grading), and heteronuclear magnetization transfer between solute and solvent peaks. Clinical applications in the next grant period include refinement of iMQC imaging methods (contrast optimization, introduction of flow compensation and presaturation), functional MRI studies on the new 3 Tesla MRI at Princeton to validate the BOLD mechanism and determine sub-voxel activation structure, and a variety of applications of spatially localized in vivo iMQC imaging. Dr. Warren proposes to do high resolution 1066 MHz NMR of macromolecules using existing magnets which give inhomogeneous fields (and removing the inhomogeneity with iMQCs) to determine the potential value of ultrahigh field NMR for protein studies. Dr. Warren also proposes to extend his work on detection of magnetization fluctuations with dipolar fields, which could evolve into another unique contrast mechanism in imaging, and which could totally transform the way low-gamma or low-concentration species are detected in NMR.