使用基于化学转移编码的成像在3T时绘制omega-3脂肪酸分量的可行性
Julius Honecker1, Olga Prokopchuk2, Claudine Seeliger1
1Else Kröner Fresenius Center for Nutritional Medicine, ZIEL-Institute for Food and Health, Technical University of Munich, Freising, Germany.
NMR in biomedicine
|June 3, 2024
概括
这项研究开发了一种新的MRI方法,用于绘制脂肪组织中的omega-3脂肪酸部分. 该技术与GC-MS有很强的相关性,证明了其在体内表征的可行性.
科学领域:
- 生物医学成像技术 生物医学成像技术
- 磁共振成像是一种磁共振成像技术.
- 生物化学 生物化学
背景情况:
- 欧米茄-3脂肪酸对健康至关重要,但它们在脂肪组织中的分布很难以非侵入的方式量化.
- 准确评估omega-3脂肪酸分数对于了解代谢健康和疾病很重要.
研究的目的:
- 开发和验证3特斯拉 (3T) 磁共振成像 (MRI) 方法,用于绘制omega-3脂肪酸分数的地图.
- 评估这种方法在幻体,体外脂肪组织样本和体内生物中的性能.
主要方法:
- 使用化学转移编码模型和间隔时间的多回声梯度回声 (TIMGRE) 序列来区分脂肪酸替代剂.
- 该方法在校准的油幻体和21个脂肪组织样本中与气相色谱-质谱学 (GC-MS) 进行了验证.
- 在两个健康志愿者的部区域测试了可行性.
主要成果:
- 在幻影和体外研究中,MRI方法与GC-MS对omega-3分数,双键数 (ndb) 和甲中断双键数 (nmidb) 的显著相关性.
- 对于平均脂肪酸链长度 (CL) 的相关性在幻体中是显著的,但在体外并非如此.
- 一个示例的体内测量显示omega-3分数为0.8%±1.9%.
结论:
- 基于渐变回声成像的omega-3脂肪酸分数映射显示了与GC-MS的强烈相关性.
- 开发的MRI技术可用于体内脂肪组织omega-3脂肪酸含量的体内特征.
相关概念视频
NMR Spectroscopy: Chemical Shift Overview
1.5K
The position of the absorption signal of a sample is reported relative to the position of the signal of tetramethylsilane (TMS), which is added as an internal reference while recording spectra. The difference between the absorption frequencies of the sample and TMS (in Hz) is divided by the spectrometer operating frequency (in MHz) to obtain a dimensionless quantity called the chemical shift. It is reported on the δ (delta) scale and expressed in parts per million.
For instance, the proton...
For instance, the proton...
1.5K
Proton (¹H) NMR: Chemical Shift
1.6K
Organic molecules primarily contain carbon and hydrogen atoms. While all the hydrogen isotopes are NMR-active, protium or hydrogen-1 is the most abundant. It has a significant energy separation between its nuclear spin states due to its large gyromagnetic ratio. As per Boltzmann's distribution, an increase in the energy separation implies a greater excess population of nuclei available for excitation, resulting in a strong NMR absorption signal.
Absorption signals of all the protium nuclei...
Absorption signals of all the protium nuclei...
1.6K
¹³C NMR: Distortionless Enhancement by Polarization Transfer (DEPT)
1.0K
When proton-coupled carbon-13 spectra are simplified by a broadband proton decoupling technique, structural information about the coupled protons is lost. Distortionless enhancement by polarization transfer (DEPT) is a technique that provides information on the number of hydrogens attached to each carbon in a molecule. While the DEPT experiment utilizes complex pulse sequences, the pulse delay and flip angle are specifically manipulated. The resulting signals have different phases depending on...
1.0K
Insensitive Nuclei Enhanced by Polarization Transfer (INEPT)
297
Insensitive Nuclei Enhanced by Polarization Transfer (INEPT) is an advanced Nuclear Magnetic Resonance (NMR) technique specifically designed to detect and enhance the signals of low-abundance nuclei, such as carbon-13 and nitrogen-15, in small molecules. The fundamental principle behind INEPT is the transfer of polarization from a more abundant and highly polarizable nucleus, typically hydrogen-1, to the low-abundance nucleus of interest. This process effectively boosts the NMR signal of the...
297
Carbon-13 (¹³C) NMR: Overview
5.6K
Carbon-13 is a naturally occurring NMR-active isotope of carbon with a low natural abundance of 1.1%. In contrast, carbon-12 is the most abundant isotope of carbon with zero nuclear spin. Therefore, it is NMR inactive. The gyromagnetic ratio of carbon-13 is smaller than that of protons. As a result, carbon-13 resonance is about 6000 times weaker than proton resonance. For a given magnetic field strength, the resonance frequency of carbon-13 is about one-fourth of the resonance frequency for...
5.6K
¹H NMR Chemical Shift Equivalence: Enantiotopic and Diastereotopic Protons
1.6K
Replacing each alpha-hydrogen in chloroethane by bromine (or a different functional group) yields a pair of enantiomers. Such protons are called prochiral or enantiotopic and are related by a mirror plane. Enantiotopic protons are chemically equivalent in an achiral environment. Because most proton NMR spectra are recorded using achiral solvents, enantiotopic hydrogens yield a single signal.
In chiral compounds such as 2-butanol, replacing the methylene hydrogens at C3 produces a pair of...
In chiral compounds such as 2-butanol, replacing the methylene hydrogens at C3 produces a pair of...
1.6K


