钆(Ⅲ)-钙试剂络合物吸附波研究

在含有 0 .1 0 mol/L KCl,p H=1 0 .2的 NH3- NH4 Cl缓冲溶液中 ,用线性扫描示波极谱法测得 Gd( ) - Cal- red络合物有一灵敏的导数波 ,峰电位在 - 0 .84V,峰电流与钆 ( )的浓度在 1 .0× 1 0 - 7～ 5 .0× 1 0 - 6 mol/L范围内呈线性关系 ,检出限达1 .0× 1 0 - 7mol/L ;另外 ,试剂本身在 - 0 .61 V有导数极谱波 ,该波的峰电流随钆( )的浓度增加而降低 ,也具有一定的线性关系     

Study on supported combined liquid membrane containing HEH（EH）P and HNO3 for trivalent gadolinium transfer

A novel kind of supported combined liquid membrane（SCLM） has been studied for the Gd（Ⅲ） transfer.SCLM contained polyvinylidene fluoride membrane（PVDF） as the liquid membrane support and renewal solution including HNO₃ solution as the stripping solution and 2-ethyl hexyl phosphonic acid-mono-2-ethyl hexyl ester（HEH（EH）P） as the carrier dissolved in kerosene. The mixed solution of carrier and kerosene was membrane solution.The optimum transport conditions of Gd（Ⅲ） were that concentration of HNO₃ solution was 4.00 mol/L,concentration of carrier was 0.16 mol/L,and volume ratio of membrane solution to stripping solution was 30:30 of the renewal phase,and pH value was 4.80 of the feed phase.Under the optimum condition studied, when initial concentration of Gd（Ⅲ） was 1.00×10^-4 mol/L,the transfer rate of Gd（Ⅲ） was 96.8%during 130 min.     

Synthesis, binding affinity, and relaxivity of target-specific MRI contrast agents

Although magnetic resonance imaging (MRI) is one of the most important imaging modalities of the central nervous system (CNS), one of the main drawbacks of MRI is its limited specificity. This can potentially be partially alleviated by target-specific contrast agents. In the present paper we describe a simple high yield synthesis of two such gadolinium-based spiperone targeted MRI contrast agents, 1a and 1b. The R₁ relaxivities of 1a and 1b were evaluated and found to be 5.94 and 8.31 mM⁻¹ s⁻¹, respectively at 9.4T, while their R₂ relaxivities at the same magnetic field were found to be 18.05 and 22.60 mM⁻¹ s⁻¹, respectively. In addition and very importantly compound 1a, which is a gadolinium-based, spiperone-targeted MRI contrast agent, was found to preserve some of the spiperone affinity toward the dopamine D2 receptor. Compounds 1a and 1b thus represent potential agents for in vitro dopamine receptor imaging using MRI in experimental models. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

三乙四胺六乙酸钆单核配合物的合成及晶体结构

在水溶液中合成了三乙四胺六乙酸(H₆ttha)钆单核配合物(NH₄)₂[Gd(Httha)]·6H₂O,获得了单晶,并测定了其结构.晶体属单斜晶系,P2₁/c空间群.晶胞参数a=1.0400(4)nm,b=1.2761(4)nm,c=2.3132(4)nm,β=90.89(3)°,V=3.070(2)nm³,Z=4,D_c=1.709g/cm³.R₁=0.0394,F(000)=1612.配合物是单核分子,每个钆离子与来自同一个三乙四胺六乙酸的4个氮原子和5个羧基氧原子配位,配位数为9,形成单帽四方反棱柱型配位多面体.     

Effect of gadolinium injection on diffusion-weighted imaging with background body signal suppression (DWIBS) imaging of breast lesions

Objectives

Diffusion-weighted imaging with background body signal suppression (DWIBS) provides both qualitative and quantitative imaging of breast lesions and are usually performed before contrast material injection (CMI). This study aims to assess whether the administration of gadolinium significantly affects DWIBS imaging.

Methods

200 patients were prospectively evaluated by MRI with STIR, TSE-T2, pre-CMI DWIBS, contrast enhanced THRIVE-T1 and post-CMI DWIBS sequences. Pre and post-CMI DWIBS were analyzed searching for the presence of breast lesions and calculating the ADC value. ADC values of ≤ 1.44 × 10^- 3 mm²/s were considered suspicious for malignancy. This analysis was then compared with the histological findings. Sensitivity, specificity, diagnostic accuracy (DA), positive predictive value (PPV) and negative (NPV) were calculated for both sequences and represented by ROC analysis. Pre and post-CMI ADC values were compared by using the paired t test.

Results

In 150/200 (59%) patients, pre and post-CMI DWIBS indicated the presence of breast lesions, 53 (35%) with ADC values of > 1.44 × 10^- 3 mm²/s and 97 (65%) with ADC ≤ 1.44 × 10^- 3 mm²/s. Pre-CMI and post-DWIBS sequences obtained the same sensitivity, specificity, DA, PPV and NPV values of 97%, 83%, 89%, 79% and 98%. The mean ADC value of benign lesions was 1.831 ± 0.18 × 10^- 3 mm²/s before and 1.828 ± 0.18 × 10^- 3 mm²/s after CMI. The mean ADC value of the malignant lesions was 1.146 ± 0.16 × 10^- 3 mm²/s before and 1.144 ± 0.16 × 10^- 3 mm²/s after CMI. No significant difference was found between pre and post CMI ADC values (p > 0.05).

Conclusion

DWIBS imaging is not influenced by CMI. Breast MR protocol could be modified by placing DWIBS after dynamic contrast enhanced sequences in order to maximize patient cooperation.     

密度泛函理论研究Gd（H2O）n^3＋（n=8，9）化合物的结构及相对稳定性

用密度泛函理论方法研究了气相和水溶液中Gd（H2O）n^3＋（n=8,9）化合物的结构和相对稳定性,其中水溶剂效应利用极化连续介质方法结合多种溶质空腔模型进行模拟．气相计算得到的化合物结构与实验观察结果一致．计算结果表明,在气相中9配位Gd（H2O）9^3＋比8配位Gd（H2O）8^3＋稳定,而在水溶液中稳定顺序刚好相反,这一结果不依赖于计算中采用的空腔模型种类,而且也与实验结果吻合．最后,通过采用各种空腔模型计算Gd^3＋的水合自由能,并与实验值比较,发现当化合物只包含第一层配位水分子时,UA0、UAHF及UAKS空腔模型最适合研究Gd^3＋在水溶液中的性质．     

Syntheses,Structures, and Magnetic Properties of Two DMTCNQ and DETCNQ Gadolinium Complexes

Two DMTCNQ (DMTCNQ = 2,5‐dimethyl‐7,7,8,8‐tetracyano‐p‐quinodimethane) and DETCNQ (DETCNQ = 2,5‐diethyl‐7,7,8,8‐tetracyano‐p‐quinodimethane) gadolinium complexes [Gd(DMTCNQ)₂(CH₃OH)(H₂O)₆][DMTCNQ] · 4H₂O ( 1 ) and [Gd(DETCNQ)(H₂O)₇][2DETCNQ] ( 2 ) were synthesized by reactions of GdCl₃ · 6H₂O with Li(DMTCNQ) or Li(DETCNQ). X‐ray diffraction analysis reveals that complexes 1 and 2 are discrete complexes. The central metal atom in 1 is coordinated by two DMTCNQ ligand radicals whereas that in 2 is coordinated by just one DETCNQ ligand radical. The adjacent molecules are connected by the intermolecular hydrogen bonds to form the two‐dimensional (2D) supramolecular layer structures, which are further packed into a three‐dimensional (3D) supramolecular architecture through the π–π interactions between ligand radicals in 1 and 2 . Magnetic investigation indicates that the antiferromagnetic interactions between spin carriers exists in 1 and 2 .