Department of Physical Chemistry, Faculty of Pharmacy, Medical University of Warsaw, Poland.
Solid State Nucl Magn Reson. 2010 Feb-Apr;37(1-2):21-7. doi: 10.1016/j.ssnmr.2010.01.001. Epub 2010 Jan 11.
(1)H, (13)C and (31)P magic angle spinning magnetic resonance spectra (MAS NMR) of lyophilized brain tissue specimens were recorded. Among the 35 cases of brain tumors there were 24 glioblastomas, seven meningiomas and a few other types. (1)H NMR measurements were performed with a MAS speed of 33 kHz. The intense CH(3), CH(2) and CH peaks in the (1)H spectrum result from fatty acid residues of phospholipids, which are "mobile enough" besides the anhydrous environment. (13)C CPMAS spectra revealed the resonances of creatine and guanidine carbons; the high intensity signals arise from carbonyl groups and methylene carbons of lipids. In particular we found a fraction of mobile lipids, characterized by narrow resonances and long T(1rho)(H) Overlapped resonances of phospholipids head groups contributed to the peak at 4-7 ppm in the (31)P MAS NMR spectra. Our results indicate that (1)H and (13)C MAS NMR are able to characterize tumor types: differentiate glioblastomas from meningiomas and shed light on tumor biochemical characteristics. However, water soluble metabolites are not observed and macromolecules yield broad overlapped resonances. Generally, lyophilization significantly decreases discriminative potential of NMR analysis.
(1)H、(13)C 和(31)P 魔角旋转磁共振谱(MAS NMR)对冻干脑组织标本进行了记录。在 35 例脑肿瘤中,有 24 例为胶质母细胞瘤,7 例为脑膜瘤,还有一些其他类型。(1)H NMR 测量在 MAS 速度为 33 kHz 的条件下进行。(1)H 谱中强烈的 CH(3)、CH(2)和 CH 峰来自磷脂的脂肪酸残基,这些残基在无水环境中“足够移动”。(13)C CPMAS 谱显示了肌酸和胍基碳的共振;高强度信号来自于羰基和脂类的亚甲基碳。特别是,我们发现了一部分移动的脂质,其特征是窄共振和长 T(1rho)(H)。磷脂头部基团的重叠共振导致了(31)P MAS NMR 谱中 4-7 ppm 处的峰。我们的结果表明,(1)H 和(13)C MAS NMR 能够对肿瘤类型进行特征分析:将胶质母细胞瘤与脑膜瘤区分开来,并揭示肿瘤的生化特征。然而,水溶性代谢物无法观察到,大分子产生宽的重叠共振。一般来说,冻干会显著降低 NMR 分析的辨别能力。