7.0T nuclear magnetic resonance evaluation of the amyloid beta(1–40) animal model of Alzheimer's disease: comparison of cytology verification

3.0T magnetic resonance spectroscopic imaging brain function in Alzheimer＇s disease. However, is a commonly used method in the research ot the role of 7.0T high-field magnetic resonance spectroscopic imaging in brain function of Alzheimer＇s disease remains unclear. In this study, 7.0T magnetic resonance spectroscopy showed that in the hippocampus of Alzheimer＇s disease rats, the N-acetylaspartate wave crest was reduced, and the creatine and choline wave crest was elevated. This finding was further supported by hematoxylin-eosin staining, which showed a loss of hippocampal neurons and more glial cells. Moreover, electron microscopy showed neuronal shrinkage and mitochondrial rupture, and scanning electron microscopy revealed small size hippocampal synaptic vesicles, incomplete synaptic structure, and reduced number. Overall, the results revealed that 7.0T high-field nuclear magnetic resonance spectroscopy detected the lesions and functional changes in hippocampal neurons of Alzheimer＇s disease rats in vivo, allowing the possibility for assessing the success rate and grading of the amyloid beta （1-40） animal model of Alzheimer＇s disease.

Investigation of formation of dimeric G-quadruplex of HIV-1 integrase inhibitor by nuclear magnetic resonance

In this research, an unusually dimeric G-quadruplex of d（GGGTGGGTGGGTGGGT） （SI）, the potent nanomolar HIV-1 integrase inhibitor, was detected by nuclear magnetic resonance （NMR）. This result has been confirmed by electrospray ionization mass spectrometry （ESI-MS） and circular dichroism （CD）.

利用^(1)H NMR测定姜中姜辣素与姜黄素

该研究采用核磁共振氢谱(proton nuclear magnetic resonance,^(1)H NMR)技术对冻干生姜与烘干生姜中的姜辣素和姜黄素类化合物的变化进行定性定量分析,发现姜中姜辣素提取物主要包括6-姜酚、8-姜酚、10-姜酚等姜酚类物质以及少量姜烯酚。经过烘干处理后,总姜酚的含量由(1.5±0.3)mg/g降低至(0.89±0.06)mg/g(鲜重),总姜辣素的含量由(2.3±0.4)mg/g降低至(1.4±0.1)mg/g,6-姜烯酚的含量由(4.8×10^(-3)±2.7×10^(-3))mg/g升高至(0.0209±0.0004)mg/g。烘干后姜黄素类化合物的含量由(4.4±0.2)mg/100 g降低至(1.5±0.6)mg/100 g,香草醛的含量由(1.20±0.07)mg/100 g升高至(1.87±0.01)mg/100 g,说明热处理会导致生姜中的姜辣素与姜黄素类化合物降解,姜酚类物质向姜烯酚转化。该试验结果为研究姜中姜辣素与姜黄素类化合物的变化机理以及姜制品的生产与工艺优化提供了参考。

3.0T 1H magnetic resonance spectroscopy for assessment ofsteatosis in patients with chronic hepatitis C

AIM To investigate the utility of 1H magneticresonance spectroscopy （1H MRS） as a noninvasivetest for steatosis in patients infected with hepatitis Cvirus.METHODS： Ninety patients with chronic hepatitisC and pathology data underwent 3.0T 1H MRS, andthe results of MRS and pathological analysis werecompared.RESULTS： This group of patients included 26 peoplewith mild fatty liver （28.89%）, 16 people withmoderate fatty liver （17.78%）, 18 people with severefatty liver （20.0%）, and 30 people without fatty liver（33.33%）. The water peak was near 4.7 parts permillion （ppm）, and the lipid peak was near 1.3 ppm.Analysis of variance revealed that differences in thelipid peak, the area under the lipid peak, ratio of thelipid peak to the water peak, and ratio of the areaunder the lipid peak to the area under the waterpeak were statistically significant among the groups.Specifically, as the severity of fatty liver increased, thevalue of each index increased correspondingly. In thepairwise comparisons, the mean lipid peak, area underthe lipid peak, ratio of the lipid peak to the waterpeak, and ratio of the area under the lipid peak to thearea under the water peak were significantly differentbetween the no fatty liver and moderate fatty liver groups, whereas no differences were noted betweenthe severe fatty liver group and the mild or moderatefatty liver group. Area under the ROC curve （AUC） ofarea ratio in lipid and water and ratio in lipid and waterin the no fatty liver group to mild fatty liver group, mildfatty liver group to moderate fatty liver group, andmoderate fatty liver disease group to severe fatty livergroup, were 0.705, 0.900, and 0.975, respectively.CONCLUSION： 1H MRS is a noninvasive techniquethat can be used to provide information on the effectof liver steatosis on hepatic metabolic processes. Thisstudy indicates that the 1H MRS can be used as anindicator of steatosis in patients with chronic hepatitis C.

Three dimensional structure prediction and proton nuclear magnetic resonance analysis of toxic pesticides in human blood plasma

The purpose of this study was to investigate the nuclear magnetic resonance （NMR） assignments of hydrolyzed products extracted from human blood plasma. The correlations between chemical, functional and structural prop- erties of highly toxic pesticides were investigated using the PreADME analysis. We observed that toxic pesticides possessed higher molecular weight and, more hydrogen bond donors and acceptors when compared with less toxic pesticides. The occurrence of functional groups and structural properties was analyzed using ~H-NMR. The ~H- NMR spectra of the phosphomethoxy class of pesticides were characterized by methyl resonances at 3.7-3.9 ppm （8） with the coupling constants of 11-16 Hz （Je-cns）. In phosphoethoxy pesticides, the methyl resonance was about 1.4 ppm （8） with the coupling constant of 10 Hz （Je-cH2） and the methylene resonances was 4.2-4.4 ppm （8） with the coupling constant of 0.8 Hz （Jp-cH3）, respectively. Our study shows that the values of four parameters such as chemical shift, coupling constant, integration and relaxation time correlated with the concentration of toxic pesticides, and can be used to characterise the proton groups in the molecular structures of toxic pesticides.

Applications of multi-nuclear magnetic resonance spectroscopy at 7T

AIM: To discuss the advantages of ultra-high field (7T) for 1H and 13C magnetic resonance spectroscopy (MRS) studies of metabolism.METHODS: Measurements of brain metabolites were made at both 3 and 7T using 1H MRS. Measurements of glycogen and lipids in muscle were measured using 13C and 1H MRS respectively.RESULTS: In the brain, increased signal-to-noise ratio (SNR) and dispersion allows spectral separation of the amino-acids glutamate, glutamine and γ-aminobutyric acid (GABA), without the need for sophisticated editing sequences. Improved quantification of these metabolites is demonstrated at 7T relative to 3T. SNR was 36% higher, and measurement repeatability (% coefficients of variation) was 4%, 10% and 10% at 7T, vs 8%, 29% and 21% at 3T for glutamate, glutamine and GABA respectively. Measurements at 7T were used to compare metabolite levels in the anterior cingulate cortex (ACC) and insula. Creatine and glutamate levels were found to be significantly higher in the insula compared to the ACC (P < 0.05). In muscle, the increased SNR and spectral resolution at 7T enables interleaved studies of glycogen (13C) and intra-myocellular lipid (IMCL) and extra-myocellular lipid (EMCL) (1H) following exercise and re-feeding. Glycogen levels were significantly decreased following exercise (-28% at 50% VO2 max; -58% at 75% VO2 max). Interestingly, levels of glycogen in the hamstrings followed those in the quadriceps, despite reduce exercise loading. No changes in IMCL and EMCL were found in the study.CONCLUSION: The demonstrated improvements in brain and muscle MRS measurements at 7T will increase the potential for use in investigating human metabolism and changes due to pathologies.

^(1)H-MRS在脑胶质瘤诊断中的研究进展

脑胶质瘤是中枢神经系统最常见的颅内恶性肿瘤,预后差。磁共振波谱成像作为能够无创检测活体组织内化学物质的磁共振功能成像,可以量化感兴趣区的不同代谢物,为更加准确地早期诊断脑胶质瘤提供帮助。本文就氢质子磁共振波谱成像在脑胶质瘤诊断评估中的研究进展进行综述。

利用^1H MRS进行在体乳腺癌中复合胆碱外参照法定量的研究

目的探讨如何用外参照法利用氢质子磁共振波谱(1HMRS)对在体乳腺癌中的复合胆碱进行绝对定量。方法配制5个不同浓度的胆碱测试模型及一个胆碱校对模型。在基本相同的条件下,对各测试模型的同一位置进行MRS采集,统计胆碱峰峰下面积与胆碱浓度之间是否呈线性相关。对水模进行T1WI成像,绘制不同位置信号强度的变化曲线。对同一校对模型的同一位置采用不同大小的体素进行MRS采集,统计体素大小与胆碱峰峰下面积是否呈线性相关。测量胆碱测试模型及校对模型中胆碱的T1及T2值。验证胆碱浓度绝对定量的校对公式。对7例乳腺癌病人进行乳腺MRS采集,利用校对公式以胆碱校对模型中的胆碱浓度为参照计算出乳腺癌中复合胆碱的浓度。结果胆碱测试模型的胆碱峰峰下面积与胆碱浓度之间呈线性相关。同一模型同一位置胆碱峰峰下面积与体素大小呈线性相关。测试模型及校对模型中胆碱的T1及T2值分别为1902.5/1032.8、2426.3/989.4。利用校对公式估计出的校对模型的胆碱浓度为(5.2±1.0)mM,与校对模型的实际浓度比较二者无显著差异(t=0.6,P>0.05)。7例乳腺癌中的复合胆碱浓度为(3.64±2.52)mM。结论外参照法是进行乳腺癌中复合胆碱浓度定量的可行及可靠的方法。

短暂性脑缺血发作与脑梗死的1^H-MRS比较研究

目的比较短暂性脑缺血发作(TIA)和脑梗死的氢质子磁共振波谱(1H-MRS)改变,探讨1H-MRS在TIA中的应用价值。资料与方法对30例TIA和24例脑梗死患者行1H-MRS检查,同期选择24名健康志愿者作为对照。分别比较TIA患者病变侧和对侧半卵圆中心、脑梗死患者梗死灶与对侧正常脑组织代谢物氮-乙酰天门冬氨酸(NAA)、胆碱(Cho)和肌酸(Cr)含量的差异,并观察有无乳酸(Lac)峰出现,再对TIA患者、脑梗死患者及正常对照组之间脑内NAA、Cho、Cr和Lac含量的差异进行比较。结果TIA患者病变侧半卵圆中心NAA降低、Cho升高,与对侧相应区域以及正常对照组比较差异均有统计学意义(P<0.01),而两侧Cr含量差异无统计学意义(P>0.05),脑梗死患者梗死灶内NAA、Cho和Cr与对侧正常脑组织和正常对照组比较均有下降,差异有统计学意义(P<0.01),但TIA患者NAA下降幅度明显小于脑梗死患者,差异有统计学意义(P<0.01);10例TIA患者、23例脑梗死患者于病侧发现Lac峰,TIA的Lac含量低于脑梗死,差异有统计学意义(P<0.01)。结论TIA患者缺血脑组织存在代谢异常,但较脑梗死轻微,1H-MRS能够早期发现这种异常,对TIA的早期诊断和治疗具有重要价值。

H-MCM-22沸石分子筛中Brnsted/Lewis酸协同效应的~1H和^(27)Al双量子魔角旋转固体核磁共振研究

采用各种固体核磁共振 (NMR) 技术详细研究了 H-MCM-22 分子筛中 Brnsted/Lewis 酸的协同效应. 二维 1H 双量子魔角旋转 (DQ-MAS) NMR 结果表明, 在脱铝 H-MCM-22 分子筛中 Brnsted 酸位 (骨架桥式羟基) 和 Lewis 酸位 (非骨架铝羟基) 之间是空间邻近的, 暗示着可能存在 B/L 酸协同效应. 二维 27Al DQ-MAS NMR 结果揭示了各种铝物种之间的空间邻近性, 表明 B/L 酸协同效应优先发生在 H-MCM-22 分子筛超笼中的骨架 T6 位铝和非骨架铝物种之间. 2-13C-丙酮探针分子实验发现, 因 B/L 酸协同效应而导致脱铝 H-MCM-22 分子筛酸性明显增强, 氘代吡啶探针分子实验也证实在 H-MCM-22 分子筛的超笼中发生了 B/L 酸协同效应. 上述结果将有助于我们理解在脱铝 H-MCM-22 分子筛上发生的多相催化机理.

Prediction of Vapor-Liquid Equilibria of Alcohol-Hydrocarbon Systems by ^1H NMR and Azeotropic Point

With the energy parameters obtained from1H nuclear magnetic resonance(NMR)chemical shifts data by local composition model and coupled with azeotropic point,the low-pressure vapor-liquid equilibrium is satisfactorily predicted for alcohol+hexane,alcohol+cyclohexane,and alcohol+benzene binary systems at different temperatures.The relationship between the spectroscopic information and thermodynamic property is presented.

^1H MRS在足月新生儿缺氧缺血性脑病中的应用

目的 通过探讨氢质子磁共振波谱与足月新生儿缺氧缺血性脑病代谢变化的关系,以评估氢质子磁共振波谱在诊断足月新生儿缺氧缺血性脑病及预后的作用.方法 研究对象为30例在临床诊断为新生儿缺氧缺血性脑病的足月新生儿与7例足月正常对照儿.所有研究对象于出生13天内进行头颅氢质子磁共振波谱检查,测量右侧基底节和右侧额叶代谢产物波峰下面积值,同时记录研究对象的胎龄、性别、分娩方式、出生体重、头颅氢质子磁共振波谱检查时的日龄、新生儿缺氧缺血性脑病临床分度等资料,于其生后第3天、第7天、第14天、第28天进行新生儿行为神经评分,并对上述资料进行统计学分析.结果 ①新生儿缺氧缺血性脑病组与对照组比较,右侧基底节和右侧额叶乳酸/肌酸、N-乙酰天门冬氨酸/肌酸、谷氨酸盐和谷氨酰胺/肌酸的比值均有统计学意义（均P〈0.05）;而右侧基底节和右侧额叶肌醇/肌酸、胆碱/肌酸的比值均无统计学意义（均P〉0.05）;②新生儿缺氧缺血性脑病轻度与中重度比较,右侧基底节和右侧额叶乳酸/肌酸、N-乙酰天门冬氨酸/肌酸、谷氨酸盐和谷氨酰胺/肌酸的比值均有统计学意义（均P〈0.05）;③新生儿缺氧缺血性脑病组右侧基底节和右侧额叶乳酸/肌酸、N-乙酰天门冬氨酸/肌酸、谷氨酸盐和谷氨酰胺/肌酸的比值与临床分度有显著相关性（均P〈0.01）;④新生儿缺氧缺血性脑病组右侧基底节和右侧额叶乳酸/肌酸、N-乙酰天门冬氨酸/肌酸、谷氨酸盐和谷氨酰胺/肌酸的比值与患儿第14天新生儿行为神经评分具有显著相关性（均P〈0.01）.结论 氢质子磁共振波谱对新生儿缺氧缺血性脑病的临床诊断及短期预后评估具有重要临床意义,值得深入研究及推广.

依达拉奉对急性脑梗死患者^1H MRS的影响

目的观察依达拉奉对急性脑梗死患者磁共振氢质子波谱(1H magnetic resonance spectroscopy,1H MRS)的影响,评价依达拉奉治疗急性脑梗死的疗效。方法选择发病24h内的急性脑梗死患者66例,随机分为依达拉奉组(35例)及对照组(31例)。对2组治疗前及4周后美国国立卫生研究院脑卒中量表评分(NIHSS评分)、N-乙酰天冬氨酸(NAA),N-乙酰天冬氨酸与肌酸(Cr)比值(NAA/Cr)进行比较。结果4周后依达拉奉组NIHSS评分(5.71±1.74)较对照组(7.26±2.87)降低明显,差异有统计学意义(P<0.05)。4周后NAA、NAA/Cr值对照组(514±118、1.67±0.23)和依达拉奉组(613±169、1.82±0.28)均较治疗前(对照组345±108、1.34±0.18;治疗组336±115、1.32±0.19)升高,但依达拉奉组升高明显,差异有统计学意义(P<0.05)。结论依达拉奉是一种有效的治疗急性脑梗死的神经保护剂。

用^(1)H定量核磁共振法同时确定成盐化合物的质量分数和各组分的比例

^(1)H定量核磁共振(^(1)H quantitative nuclear magnetic resonance,^(1)H qNMR)方法具有操作简便、实验快速等优点.本文通过该方法可准确测定富马酸丙酚替诺福韦在样品中的含量,并给出丙酚替诺福韦和富马酸的比例,结果与其他分析测试所得结果相符.该方法以氘代二甲基亚砜(DMSO-d^(6))为溶剂,采集待测样品的核磁共振氢谱,对比丙酚替诺福韦定量峰、富马酸定量峰与内标物响应峰面积,分别计算丙酚替诺福韦和富马酸的质量分数.富马酸丙酚替诺福韦和富马酸与内标物的质量比值在0.91~1.24范围内线性关系良好,^(1)H qNMR法测得二者质量分数分别为100.06%和10.90%,与质量平衡法测得的结果基本一致.本研究建立的核磁共振定量方法不仅可准确、快速地测定丙酚替诺福韦和富马酸这2种成分的质量分数和比例,还为多组分、成盐的化学原料药的比例确定、绝对含量测定提供参考.

^1H—MRS对碘异常引起脑损伤的诊断价值

目的探讨氢质子磁共振波谱分析(1H-MRS)在碘异常引起脑损伤病变中的应用价值。方法收集临床诊断碘异常引起脑损伤的病例28例,其中低碘组16例,高碘组12例。使用西门子1.5 T MRI,多体素相位矩阵扫描。检测低碘组和高碘组病人海马区与正常参照区域的代谢物浓度,利用SPSS12.0分析各种代谢物的变化。结果1H-MRS示低碘组胆碱降低、γ-氨基丁酸、N-乙酰天门冬氨酸减少;高碘组胆碱增加、谷氨酸升高,γ-氨基丁酸、N-乙酰天门冬氨酸减少。结论1H-MRS在碘异常引起脑损伤病变定性诊断中有重要的临床价值。

基于^(1)H NMR的代谢组学技术在食品掺假及溯源分析中的研究进展

受产地、加工、贮存以及运输过程中的各种影响,引起食品的复杂性和可变性,导致食品的掺假及溯源分析具有一定的挑战性。现有的食品掺假溯源方法主要集中在理化测试及分子生物学技术等方面,相关鉴别的准确性有待提高。基于核磁共振氢谱(^(1)H NMR)的代谢组学技术与多元统计分析相结合,可以完整地描述食品的整体特征,收集食品的产地、品质等信息,近来在食品领域应用较为广泛,已成为食品质量分析和溯源等的有力工具。本文阐述了^(1)H NMR组学技术在农产食品掺假及溯源分析中的应用进展,在概述^(1)H NMR技术原理的基础上,针对^(1)H NMR与化学计量学分析方法的结合及其应用进行了介绍,对其在典型性食品的掺假及产地溯源上的研究进行了概括总结,旨在为^(1)H NMR组学技术在食品品质分析中的研究及应用提供理论参考。

利用^(1)H NMR分析小龙虾的特征性滋味组成

为深入研究小龙虾的非挥发性滋味活性物质,利用^(1)H核磁共振(nuclear magnetic resonance,NMR)对小龙虾中游离氨基酸、核苷酸、有机酸、可溶性糖和生物碱等滋味成分进行定性定量分析,并采用味道强度值(taste activity value,TAV)分析其味觉活性成分,以及通过味精当量(equivalent umami concentration,EUC)评价鲜味。结果表明,使用^(1)H NMR共检测到小龙虾中33种滋味化合物,其中精氨酸、组氨酸、谷氨酸、丙氨酸、赖氨酸、甘氨酸、5’-单磷酸腺苷二钠、5’-单磷酸肌苷二钠、琥珀酸和乳酸的TAV大于1,它们对小龙虾的滋味有重要影响。EUC值以谷氨酸钠质量计,发现小龙虾样品的EUC值为9.1 g/100 g,说明小龙虾具有非常强烈的鲜味。

基于^(1)H-NMR的冠心病血瘀证、痰浊证的代谢组学研究

目的:冠心病以其极高的发病率严重威胁着人类的健康,对冠心病药物治疗及作用靶点的研究仍非常迫切。本研究旨在运用核磁共振氢谱(^(1)H nuclear magnetic resonance spectroscopy,^(1)H-NMR)代谢组学技术建立冠心病血瘀证及痰浊证的指纹代谢图谱,寻找这2种证型的血浆标志性代谢物,并揭示血府逐瘀汤治疗冠心病血瘀证的机制。方法:采集符合纳入标准的69例冠心病血瘀证患者、60例冠心病痰浊证患者及40例健康对照受试者的清晨空腹血浆,基于^(1)H-NMR构建冠心病血瘀证及痰浊证的^(1)H-NMR指纹代谢图谱。使用多元统计分析方法主成分分析(principal component analysis,PCA)、正交化偏最小二乘判别分析(orthogonal partial least squares discriminant analysis,OPLS-DA)寻找冠心病血瘀证及冠心病痰浊证的标志性代谢物。随机抽取冠心病血瘀证患者30例,予血府逐瘀汤治疗30 d,对治疗前后的清晨空腹血浆进行^(1)H-NMR检测,分析冠心病血瘀证患者服药前后标志性代谢物的变化。结果:冠心病血瘀证组与对照组存在显著性差异的代谢物有以下15种:3-羟基丁酸、乳酸、丙氨酸、谷氨酸、谷氨酰胺、丙酮酸、磷脂酰胆碱、甘油磷脂酰胆碱、甘氨酸、葡萄糖、苯丙氨酸、柠檬酸、酪氨酸、甲酸盐、极低密度脂蛋白,除葡萄糖、3-羟基丁酸、极低密度脂蛋白水平升高外,其他12种代谢物水平均下降。冠心病痰浊证组与对照组存在显著性差异的代谢物有以下16种:缬氨酸、乳酸、丙氨酸、N-乙酰-β-葡萄糖苷酶、谷氨酸、谷氨酰胺、丙酮酸、肌酸、胆碱、甘氨酸、葡萄糖、苯丙氨酸、柠檬酸、组氨酸、酪氨酸、甲酸盐,除葡萄糖和胆碱2种水平升高外,其他14种代谢物水平均下降。冠心病血瘀证患者服用血府逐瘀汤治疗后胆碱、磷脂/甘油磷脂类、肌酸、脂质、柠檬酸水平升高,乳酸水平下降。结论:^(1)H-NMR结合多元统计学方法能够建立诊断冠心病血瘀证和痰浊证证型的有效模型,找到证型相关标志性代谢物;血府逐瘀汤可通过调节脂质代谢、能量代谢治疗冠心病血瘀证。

高场磁共振成像^(1)H/^(31)P双调谐射频线圈研究进展

在众多可产生磁共振现象的原子核中,1H核凭借其在生物体中含量高、磁共振信号强的优势,成为磁共振成像的主要研究对象.但其它杂核在生命科学相关研究中同样具有不可替代的独特性,如31P核广泛参与了生物体内的能量代谢过程,是非质子成像研究领域的重要内容.MRI向更高场强的发展使得杂核成像逐渐普及,其核心部件是高质量的^(1)H/^(31)P双调谐射频线圈.本文总结了与^(1)H/^(31)P双调谐射频线圈相关的研究与应用,展示了9.4 T下小鼠脑的质子磁共振成像及磁共振磷谱,并讨论了高场^(1)H/^(31)P双调谐射频线圈的潜在应用价值.

^(1)H-MRS、Dixon水脂分离与Z谱成像技术在大鼠棕色脂肪上的量化比较

目的比较^(1)H-MRS、Dixon水脂分离与Z谱成像技术在体模以及大鼠棕色脂肪上的脂肪量化结果。方法首先,制作6个脂肪含量分别为0%、20%、40%、60%、80%、100%的油水混合体模,共同放置于50 mL离心管内。依次采用ZS-MRI、^(1)H-MRS和Dixon水脂分离技术对体模的脂肪含量进行定量评估,其结果与体模脂肪真实值相比较。其次,使用ZS-MRI和Dixon水脂分离技术分别采集了六只大鼠肩胛间的数据,并计算出水脂分布图,并将结果与^(1)H-MRS定量结果进行比较。结果ZS-MRI可以很好地准确定量并区分出各个不同脂肪含量的体模(Y=0.95*X+1.48);能较好地区分棕色脂肪与白色脂肪,并与Dixon方法得到的脂肪含量在空间分布上高度一致。在棕色脂肪的量化上,ZS-MRI结果与^(1)H-MRS结果相比无显著性差异(P=0.35)。结论ZS-MRI作为一种新的脂肪定量方法,可以生成无伪影的脂肪分布图,用于定量测量大鼠体内棕色脂肪的含量以及分布。