Magnetic resonance imaging of the pancreas in streptozotocin-induced diabetic rats: Gadofluorine P and Gd-DOTA

AIM: To investigate the performance of Gadofluorine P-enhanced magnetic resonance imaging(MRI) on the diagnosis of diabetes in a streptozotocin(STZ)-induced diabetic rat model.METHODS: Fischer 344 rats were treated with STZ.Rats not treated with STZ served as controls. T1-weighted MRI was performed using a 3T scanner before and after the injection of Gd-DOTA or Gadofluorine P(6 diabetic rats, 5 controls). The normalized signal intensity(SI) and the enhancement ratio(ER) of the pancreas were measured at each time point, and the values were compared between the normal and diabetic rats using the Mann-Whitney test. In addition,the values were correlated with the mean islet number.Optimal cut-off values were calculated using a positive test based on receiver operating characteristics.Intrapancreatic Gd concentration after the injection of each contrast media was measured using laser ablation-inductively coupled plasma-mass spectrometry in a separate set of rats(4 diabetic rats, 4 controls for Gadofluorine P; 2, 2 for Gd-DOTA).RESULTS: The normalized SI and ER of the pancreas using Gd-DOTA were not significantly different between diabetic rats and controls. With Gadofluorine P, the values were significantly higher in the diabetic rats than in the control rats 30 min after injection(P < 0.05). The area under the receiver operating characteristic curve that differentiated diabetic rats from the control group was greater for Gadofluorine P than for Gd-DOTA(0.967 vs 0.667, P = 0.085). An increase in normalized SI 30 min after Gadofluorine P was correlated with a decrease in the mean number of islets(r 2 = 0.510, P = 0.014). Intra-pancreatic Gd was higher in rats with Gadofluorine P injection than Gd-DOTA injection(Gadofluorine P vs Gd-DOTA, 7.37 vs 0.00, P < 0.01). A significant difference in the concentration of intrapancreatic Gd was observed between the control and diabetic animals that were sacrificed 30 min after Gadofluorine P injection(control vs diabetic, 3.25 ng/g vs 10.55 ng/g, P < 0.05)CONCLUSION: In this STZ-induced diabetes rat model,Gadofluorine P-enhanced MRI of the pancreas showed high accuracy in the diagnosis of diabetes.

在短、宽口径,1.5T系统中的全身增强MR血管成像:Gd-BOPTA和Gd-DOTA的个体对照

全身增强磁共振血管成像(CE-MRA)"一站式"扫描能够提供全部循环系统的信息。短、宽口径扫描仪可能因Z轴视野受限而还未能应用于全身CE-MRA。

新型Gd基T_2造影剂的制备和应用

设计并合成了结构为TPP-Lys(Acp-DOTA-Gd)-COOH(简称Gd-DOTA-TPP)的小分子磁共振探针,通过电转染的方式用探针标记人源脐带间充质干细胞(hMSCs).11.7 T磁共振成像(MRI)扫描结果表明,Gd-DOTA-TPP标记的hMSCs在细胞内Gd含量为9×10~9 Gd/cell时,T_2加权信号强度即可低至背景信号强度,呈现较强暗信号.将Gd-DOTA-TPP标记的hMSCs移植入小鼠脑室,可明显提高移植干细胞在MRI设备上的检测灵敏度,检测限可低至10~3个细胞.

α-十四烷基-DOTA及其钆(Ⅲ)螯合物的合成与表征(英文)

Synthesis and characterization of the ligand,[10-( α -tetradecylcarboxymethyl)-1,4,7,10-tetraazacyclododecane-1,4,7-triacetic acid,H 4 L]and its Gd (Ⅲ) chelate are described.Protonation constants for H 4 L(lgK iH =10.62,9.50,4.74,4.12)and the stability constant for GdL - (lgK GdL - =24.60)were determined by potentiometric titrations.The results obtained show that the basicity of the ligand is not significantly altered and the ligand still maintains the strong chelating properties of the parent DOTA after introduction of a linear chain tetradecyl group at the acetic side chain of DOTA.

钆特酸葡胺与钆喷酸葡胺在肝脏血管增强效能中的对比研究

目的:通过对比钆特酸葡胺(Gd-DOTA)与钆喷酸葡胺(Gd-DTPA)在肝脏血管中的应用,观察两种对比剂的MRI增强效能。方法:收集我院2016年11月-2017年2月期间参与肝脏血管增强受试者146例,其中Gd-DOTA组81例,男性67例,女性14例,年龄26~74岁,平均年龄52.53±10.73岁;GdDTPA组65例,男性41例,女性24例,年龄27~86岁,平均年龄52.16±10.89岁。所有受试者均在同台机器进行、应用相同序列,采用Siemens Skyra 3.0T智多星DOT技术行肝脏MRI平扫及动态增强扫描,分别测量肝脏动态增强过程中蒙片、动脉期、门脉期、延迟期各期图像的噪声及肝动脉、门静脉、腹主动脉的信号强度,计算得到信噪比、对比噪声比。并对整体图像质量与增强效果进行评分。结果:Gd-DOTA组腹主动脉在肝脏动态增强动脉期、门脉期、延迟期的SNR、CNR均高于Gd-DTPA组(P值分别为0.544、0.508;0.940、0.962;0.496、0.553),两者差异无统计学意义;Gd-DOTA组门静脉在肝脏动态增强动脉期、门脉期、延迟期的SNR、CNR值分别高于Gd-DTPA组(P值分别为0.494、0.383;0.766、0.766;0.535、0.654),两者差异无统计学意义。Gd-DOTA组肝动脉在肝脏动态增强动脉期、门脉期、延迟期的SNR、CNR值分别高于Gd-DTPA组(P值分别为0.790、0.920;0.443、0.236;0.338、0.248),但两者差异无统计学意义。两组在图像质量与增强效果评分上无明显统计学差异,P值均>0.05。结论:Gd-DOTA在肝脏血管动态增强各期的信噪比、对比噪声比均非劣于Gd-DTPA。

两种具有高弛豫率的双核非离子型磁共振对比剂（英文）

磁共振成像技术被广泛应用于诊断医学和软组织成像,而磁共振对比剂有助于提高成像对比度.报道了两种基于钆-DOTA-酰肼结构的新型双核非离子型磁共振对比剂[(Gd-DOTAH)2-DYMB和(Gd-DOTAH)2-DYMBP]的设计、合成及弛豫性能.在0.5 T磁场下,测得其纵向弛豫率分别为每分子11.4和11.7 L·mmol^(-1)·s^(-1)或5.7和5.9 L·mmol^(-1)·Gd^(-1)·s^(-1),高于目前临床使用的单核大环对比剂钆-DOTA.体外磁共振成像研究显示该两种磁共振对比剂具有提高诊断灵敏度和准确度的应用潜力.

一种大环类双核非离子型磁共振对比剂的合成及弛豫性能

磁共振成像技术被广泛应用于诊断医学和软组织成像,而磁共振对比剂有助于提高成像对比度.报道了一种基于钆-DOTA-酰肼结构(DOTA=1,4,7,10-四氮杂环十二烷^(-1),4,7,10-四乙酸)的新型双核非离子型磁共振对比剂(Gd-DOTAH)2-SBDC的设计、合成及弛豫性能.在0.5 T磁场下,测得其纵向弛豫率为每分子10.6 L•mmol^(-1)•s^(-1)或5.3 L•mmol^(-1)•Gd^(-1)•s^(-1),高于目前临床使用的单核大环对比剂钆-DOTA.体外磁共振成像研究显示该磁共振对比剂具有提高诊断灵敏度和准确度的特点.同时,该对比剂分子中含有能与髓鞘特异性结合的二苯乙烯结构,具有成为髓鞘靶向磁共振对比剂的应用潜力.另外,探讨了该对比剂的两条合成路线(A和B),总收率分别为70%和75%.综合考虑适用性,合成路线B更优.