Gd-DTPA

摘要： 目的:探讨手足口病患儿合并中枢神经系统感染的低场MRI表现.方法:回顾性分析18例EV71感染小儿手足口病合并脑炎的低场0.2 TMRI表现.结果:13例病灶局限在脑桥和延髓交界部,2例病灶以脑桥和延髓交界为主向两侧延伸,2例病灶位于脑桥偏背侧,1例位于中脑.8例病变均呈略长T1、长T2班片状信号,边界欠清,FLAIR成像表现为高信号.结论:小儿手足口病合并脑炎于低场0.2 TMRI表现主要位于脑桥和延髓交界区斑片状信号,MRI能清晰显示手足口病患儿合并中枢神经系统感染的病变特点,是影像学首选检查方法,为临床诊断治疗、评价治疗效果提供了可靠依据.%Objective:To investigate the low-field MRI findings of central nervous system infection in hand-foot-and-mouth disease. Methods:The low-field 0.2 TMRI findings of 18 children with hand-foot-and-mouth disease complicated with encephalitis were retrospectively analyzed. Results:13 cases were confined to the junction of brain bridge and medulla oblongata, 2 cases were extended to both sides by the junction of brain bridge and medulla oblongata, 2 cases were located on the dorsal side of brain bridge.1 case was located in midbrain. All the lesions showed T1 and T2 patchy signals, and the boundary was not clear. The FLAIR imaging showed high signal. Conclusion:The 0.2 TMRI manifestations of handfoot-and-mouth disease with encephalitis in low field are mainly patchy signals at the junction of pons and medulla oblongata. MRI can clearly show the pathological features of hand-foot-and-mouth disease with central nervous system infection.It is the preferred imaging examination method and provides a reliable basis for clinical diagnosis, treatment and evaluation of therapeutic effect.

摘要： 背景:随着现代分子影像学的进步,使骨髓间充质干细胞干预肿瘤效能的实时监测成为可能.目的:构建新型转移相关MRI分子影像探针Gd-RGD,通过MRI成像在体观察骨髓间充质干细胞干预前后肝癌转移和增殖行为的变化.方法:构建MR转移相关因子分子影像探针整合素αvβ3配体cRGD-PEG-DGL-DTPA-Gd(Gd-RGD),并进行1H-MRS及ICP-AES分析鉴定.制作高转移潜能MHCC97-H和低转移潜能MHCC97-L肝癌动物模型,尾静脉注射骨髓间充质干细胞悬液干预6周,计算肿瘤质量抑制率.骨髓间充质干细胞干预后分别用Gd-DTPA和Gd-RGD两种示踪剂进行MRI成像实验,以SNR和CNR为半定量指标.将MHCC97-H和MHCC97-L与骨髓间充质干细胞进行Transwell共培养,置于37°C,体积分数为5%CO2培养箱内培养48 h后采用qPCR法检测转化生长因子β1、骨桥蛋白、整合素亚单位αv和β3的表达.结果与结论:①经骨髓间充质干细胞干预后,肝癌肿瘤组织质量明显降低.在第3周时,肿瘤质量抑制率最高;②对于高转移潜能肝癌(MHCC97-H),骨髓间充质干细胞干预后Gd-RGD成像SNR和CNR低于骨髓间充质干细胞干预前(P0.05),骨髓间充质干细胞干预后CNR低于骨髓间充质干细胞干预前(P0.05).低转移潜能细胞(MHCC97-L)与骨髓间充质干细胞共培养后,骨桥蛋白、β3、转化生长因子β1、αv表达均下降(P<0.05);⑤结果表明,MRI成像中Gd-DTPA和Gd-RGD示踪剂CNR指标可以很好地区分两种具有高低转移潜能肝癌组织,在骨髓间充质干细胞干预后MRI成像中Gd-DTPA和Gd-RGD示踪剂SNR、CNR指标均可以很好地区分两种具有高低转移潜能肝癌组织,且Gd-RGD效果更优.

摘要： 背景：随着现代分子影像学的进步，使骨髓间充质干细胞干预肿瘤效能的实时监测成为可能。目的：构建新型转移相关MRI分子影像探针Gd-RGD，通过MRI成像在体观察骨髓间充质干细胞干预前后肝癌转移和增殖行为的变化。方法：构建MR转移相关因子分子影像探针整合素αvβ3配体cRGD-PEG-DGL-DTPA-Gd（Gd-RGD），并进行1H-MRS及ICP-AES分析鉴定。制作高转移潜能MHCC97-H和低转移潜能MHCC97-L肝癌动物模型，尾静脉注射骨髓间充质干细胞悬液干预6周，计算肿瘤质量抑制率。骨髓间充质干细胞干预后分别用Gd-DTPA和Gd-RGD两种示踪剂进行MRI成像实验，以SNR和CNR为半定量指标。将MHCC97-H和MHCC97-L与骨髓间充质干细胞进行Transwell共培养，置于37 °C，体积分数为5% CO2培养箱内培养48 h后采用qPCR法检测转化生长因子β1、骨桥蛋白、整合素亚单位αv和β3的表达。结果与结论：①经骨髓间充质干细胞干预后，肝癌肿瘤组织质量明显降低。在第3周时，肿瘤质量抑制率最高；②对于高转移潜能肝癌（MHCC97-H），骨髓间充质干细胞干预后Gd-RGD成像SNR和CNR低于骨髓间充质干细胞干预前（P 〈 0.05）。对于低转移潜能肝癌（MHCC97-L），骨髓间充质干细胞干预前后Gd-RGD成像SNR比较差异无显著性意义（P 〉 0.05），骨髓间充质干细胞干预后CNR低于骨髓间充质干细胞干预前（P 〈 0.05）；③骨髓间充质干细胞干预后Gd-RGD成像SNR在高、低转移潜能肝癌之间差异有显著性意义（P 〈 0.05）；Gd-DTPA成像SNR和CNR差异不如Gd-RGD成像差异显著；④高转移潜能细胞（MHCC97-H）与骨髓间充质干细胞共培养后，骨桥蛋白、整合素亚单位β3、转化生长因子β1表达有明显的下降（P 〈 0.05），而αv表达无明显变化（P 〉 0.05）。低转移潜能细胞（MHCC97-L）与骨髓间充质干细胞共培养后，骨桥蛋白、β3、转化生长因子β1、αv表达均下降（P 〈 0.05）；⑤结果表明，MRI成像中Gd-DTPA和Gd-RGD示踪剂CNR指标可以很好地区分两种具有高低转移潜能肝癌组织，在骨髓间充质干细胞干预后MRI成像中Gd-DTPA和Gd-RGD示踪剂SNR、CNR指标均可以很好地区分两种具有高低转移潜能肝癌组织，且Gd-RGD效果更优。

摘要： 目的:探讨CDT序列不同翻转角在肝脏动脉期扫描中的应用,以期确定提高检出率的最佳角度.方法:2014年1月至2015年1月我院收治的120例肝占位的患者行CDT序列增强扫描,应用Gd-DTPA对比剂,以4个不同翻转角12°、15 °、18°、22°分别扫描,测定所得到的肝多动脉期图像的病灶信噪比(SNR)、对比噪声比(CNR),比较4个翻转角的CNR、SNR情况并分析.结果:12°、15°、18°、22°四个翻转角的SNR分别为213.21±30.40、242.12±35.20、252.54±32.82及261.26±41.02;12°、15°、18°、22°四个翻转角的CNR分别为228.72±31.32、241.27±30.44、270.56±36.54及290.48±42.25;SNR、CNR值随着翻转角度数的增加明显增加,四个翻转角组间比较差异均显著有统计学意义(P＜0.05).结论:大翻转角CDT序列增强肝动脉期扫描,有助于提高肝脏小病灶的检出率.

摘要： Observation of flow distribution pattern in the hemodialyzers is significant as it is a valuable in-dication of the performance of these modules. Therefore, in this study, a feasible non-destructive Magnetic Resonance Imaging (MRI) technique is proposed to characterize the flow distribution in the blood compartment of hemodialyzers using Gd-DTPA MRI contrast agent. The distribution of flow is qualitatively observed in two commercial clinical dialyzers through an in-vitro experiment. The contrast enhanced T1 weighted images are acquired along the dialyzer length using Spin Echo (SE) pulse sequence after an injection of 0.5 mmol/L Gd-DTPA solution into the blood compartment. Although relatively uniform flow distribution pattern over the spatial volume of transverse images, close the dialyzer inlet is observed, the heterogeneity of flow distribution can be identified towards the blood outlet port. Furthermore, the signal intensity profiles formed by the injected Gd-DTPA are gradually decreased towards the outlet port. These results of the study suggest that although no advanced techniques and protocols available, MRI and Gd-DTPA contrast agent can be utilized to characterize the flow distribution within a dialyzer qualitatively.

摘要： Objective To investigate the imaging characteristics of USPIO-enhanced and Gd-enhanced MRI in atherosclerosis and to compare the detection rate of atherosclerotic plaque between them. Methods Thirty-five healthy male rabbits were assigned to experimental group (n=30) to establish a model of atherosclerosis by damaging aortic tunica intima with Foley′s tube in combination with a high fat diet and 5 to control group without any intervention. At week 12, USPIO-enhanced and Gd-enhanced MRI scanning were conducted to compare the signal changes of atherosclerotic plaque before and after enhancement with the 2 contrast media. Ninety seven pictures were randomly selected respectively from the pictures enhanced by the 2 contrast media to compare the detection rate plaque between them. Pthology examination was used for detection standard. For the control group , pictures were randomly selected. Results In the experimental group, 7 rabbits died of Foley′s tube damaging, 2 died of raising and 1 died of anesthesia. All 5 rabbits in control group survived. A total of 172 pathological sections were made with 134 plaques and 72 vulnerable plaques pathologically confirmed. In pictures enhanced by USPIO , 84 plaques were confirmed by HE staining with a detection rate of 86.6%. In pictures enhanced by Gd, 72 plaques were confirmed by HE staining with a detection rate of 74.2%. Detection rate of USPIO-enhanced MRI in atherosclerosis plaque was significantly higher than that of Gd-enhanced MRI (X2=3.96, P=0.046). Conclusion USPIO shows its superiority as a new contrast medium in detection of atherosclerosis plaque.%目的：初步探讨USPIO（羧基化三氧化二铁磁性纳米颗粒）增强MR与Gd-DTPA增强MR在动脉粥样硬化中的成像特点，比较两者对动脉粥样硬化斑块的检出率。方法：健康雄性新西兰大白兔35只，随机分为两组，实验组30只采用球囊导管损伤腹主动脉结合高脂饮食的方法建立兔动脉粥样硬化模型。对照组5只不做干预。12周后给予平扫、Gd-DTPA增强扫描、USPIO增强扫描。分别从两种对比剂增强的图像中各随机挑选97幅，与病理检查结果行对照研究，比较两者斑块的检出率。对照组任意取材对照。结果：实验组7只球囊损伤时意外死亡，2只死于喂养，1只死于实验麻醉，20只存活。对照组5只全部存活。制成172张病理切片，病理证实134个斑块组织，易损斑块72个。USPIO增强图像中经病理HE证实斑块84幅，检出率为86．6％；钆剂增强图像中HE切片证实斑块72幅，检出率为74．2％。斑块检出率比较字2＝3．96，P＝0．046。结论：USPIO增强MRA对斑块的检出率明显高于传统钆剂增强MR对斑块的检出率。 USPIO作为新型核磁对比剂对于动脉粥样硬化的检测具有明显的优越性。

摘要： 目的 应用MRI示踪技术,定量分析与观察手十二井穴刺络放血后脑卒中好发脑区(丘脑及大脑中动脉供血区)脑细胞外间隙的解剖与组织液流动速率的变化规律,探讨该法对脑卒中神经保护的可能机制.方法 成年雄性SD大鼠(32只),随机分为丘脑放血组、丘脑对照组、尾状核放血组、尾状核对照组,每组各8只.丘脑放血组及尾状核放血组接受手十二井穴放血后,将2 μL 10 mmol/L GD-DTPA分别导入成年大鼠丘脑区及尾状核区,在导入前后分别进行脑MRI动态扫描(0,15 min、30 min、1h、2h、3h、4h、5h、6h、7h),利用图像后处理技术,定量分析丘脑区及尾状核区脑组织液引流以及脑细胞周围间隙迂曲度等参数的变化规律.结果 丘脑放血组脑组织液流动速率下降,清除时间延长,半衰期达(1.34±0.19)h,长于丘脑区对照组(0.51±0.13)h,差异有统计学意义(P＜0.05);局部微观清除率为(7.60±4.18)×10-5/s,明显小于丘脑对照组[(14.40±4.50) ×10-5/s],差异有统计学意义(P＜0.05).丘脑放血组丘脑区脑细胞周围间隙迂曲度为(1.29±0.32),与丘脑对照组(1.28±0.17)比较,差异无统计学意义(P＞0.05).尾状核放血组及对照组之间的各项参数未见明显变化,差异无统计学意义(P＞0.05).结论 手井穴刺络放血可明显改变丘脑区组织液流速,但对大脑中动脉供血区的脑组织液引流速率没有明显影响.由于刺络放血后丘脑区细胞外间隙的迂曲度没有明显变化,因此,其流速下降应与神经元代谢水平的下调有关,而代谢水平的下调可能是卒中时该法神经保护的机制.

摘要： Gd-DTPA was the contrast agent widely used in clinical MRI for contrast enhancement. However, the short imaging time and the nonspecific distribution in vivo limit its utility in focal lesion detection and diagnosis. 5-(4-Aminophenyl)-10, 15, 20-tripyridineporphyrin (APTMPyP) was chosen as a tumor-targeting group. A ligand containing porphyrin groups was then synthesized by the incorporation of APTMPyP into diethylenetriaminepentaacetic dianhydride (DTPAA). This ligand obtained was further reacted with gadolinium chloride to make corresponding tumor-targeting gadolinium complex Gd-DTPA-2APTMPyP. The ligand and gadolinium complex were characterized by infrared spectrum,Fourier Transform Infrared Spectrometer(FT-IR), Ultraviolet spectrometry(UV) , etc and their properties in vitro were also evaluated. Gd-DTPA-2APTMPyP possesses obviously higher relaxation effectiveness and slightly higher cytotoxicity to Hela cells than those of Gd-DTPA. Therefore Gd-DTPA-2APTMPyP can be used as a potential contrast agent in targeted MRI to tumors.%针对临床上广泛应用的磁共振成像造影剂二乙三胺五乙酸钆(Gd-DTPA)是一种离子型造影剂,由于其成像时间短、渗透压较高,没有组织或器官选择性(靶向性),尤其对早期肿瘤的成像检测效果较差的问题,利用卟啉对肿瘤的特异亲和性,将5-(4-氨基苯基)-10,15,20-三吡啶基卟啉与二乙三胺五乙酸双酸酐(DTPAA)进行化学反应,合成了一种小分子配体(DTPA-2APTMPyP),再与金属钆离子Gd(Ⅲ)配合,从而制备了小分子磁共振成像造影剂(Gd-DTPA-2APTMPyP).并对所合成的配体及其配合物进行了红外光谱、紫外光谱与核磁共振等结构表征,证明产品为目标产物.同时初步测定了配合物的体外弛豫率与细胞毒性.实验表明,与临床应用的小分子造影剂二乙三胺五乙酸钆(Gd-DTPA)相比,这种小分子造影剂具有较高的弛豫率与略高的体外细胞毒性.