二乙基二硫代氨基甲酸钠驱镍作用的实验研究

本文用大鼠研究了带-SH基的二乙基二硫代氨基甲酸钠(Dithiocarb,简称Na-DDC或称铜试剂)和不带-SH基的新螯合剂(H-73-10)的驱镍作用。结果表明,Na-DDC对羰基镍(Ni(CO)_4〕的驱镍作用明显优于H-73-10;与此相反,H-73-10对硝酸镍〔Ni(NO_3)_2〕染毒大鼠的驱镍作用却明显优于Na-DDC。     

螯合吸附分离功能纤维的研究进展

螯合纤堆是一类能与金属离子形成多配位络合物的纤堆状吸附功能材料，是近年来发展起来的一种新型离子交换纤堆，具有吸附选择性高、易洗脱、容易再生等优点。综述了近年来螯合纤堆的制备方法及种类，对其螯合机理进行了探讨，概括了该纤堆的应用范围并指出了其应用前景。     

细胞内钙离子螯合剂抑制HSV-1诱导Hela细胞的凋亡作用

目的：探讨HSV-1在诱导Hela细胞凋亡中，细胞内游离钙浓度的变化及钙离子螯合剂对HSV-1诱导Hela细胞凋亡的抑制作用。方法：HSV-1感染Hela细胞后，用扫描电镜及透射电镜观察凋亡情况。用荧光探针标记细胞内游离Ca^2 ，在不同时间观察细胞内游离Ca^2 浓度的变化。结果：HSV-1感染Hela细胞后，出现了典型的凋亡形态学变化。细胞内游离Ca^2 浓度在HSV-1感染Hela细胞后12h达高峰；典型的凋亡形态学变化出现在HSV-1感染Hela细胞后24h。细胞内Ca^2 螯合剂能显著抑制HSV-1诱导的Hela细胞凋亡。结论：细胞内游离Ca^2 在HSV-1诱导的Hela细胞凋亡过程中，具有重要作用，此实验结果为临床治疗相关疾病提供了有用的线索。     

含有纯化标签的重组人表皮生长因子的构建及表达

目的:高效表达和制备有活性的人表皮生长因子(hum an ep iderm al growth factor,hEGF)。方法:用DNA重组技术构建EGF基因并插入表达载体pQE-40,与载体上的6×H is标签融合,获得的表达质粒pQE-EGF转化E.coliM15[pREP4],得工程菌M15[pQE-EGF]。MTT法测定活性,培养工程菌M15[pQE-EGF]并诱导目的蛋白表达,镍离子螯合亲和层析纯化重组EGF。结果:所构建的EGF序列正确,重组EGF在大肠杆菌中以包涵体形式存在,表达量占菌体总蛋白的21.2%,经镍离子亲和层析一步纯化后的重组EGF纯度达90%,得率为94%。复性后的重组EGF具有促Hela细胞生长活性。结论:以E.coliM15[pREP4]/pQE-40系统表达EGF具有技术路线简单、目的蛋白得率高、成本低等优点,是一种制备活性hEGF的有效手段。     

离子络合紫外分光光度法测定葛根素及其制剂的含量

目的:建立葛根素及其制剂含量测定的新方法.方法:在一定pH条件下,葛根素和Al3 形成络合物,在339.8 nm波长处通过测定吸收度的改变来测定含量.结果:吸收度和含量之间存在一定的线性关系,C=-103.741△A-5.3437(r=-0.9994,线性范围在3.648～29.184 mg· L-1),平均加样回收率为99.87%,RSD为0.53%.结论:可用本方法测定葛根素及其制剂的含量.     

Reversible lesions in the brain parenchyma in Wilson’s disease conifrmed by magnetic resonance imaging：earlier administration of chelating therapy can reduce the damage to the brain

The aim of this study was to evaluate the resolution of brain lesions in patients with Wilson’s disease during the long-term chelating therapy using magnetic resonance imaging and a possible signiifcance of the time latency between the initial symptoms of the disease and the introduction of this therapy. Initial magnetic resonance examination was performed in 37 patients with proven neurological form of Wilson’s disease with cerebellar, parkinsonian and dystonic presentation. Magnetic resonance reexamination was done 5.7 ± 1.3 years later in 14 patients. Patients were divided into： group A, where chelating therapy was initiated 〈 24 months from the ifrst symp-toms and group B, where the therapy started≥ 24 months after the initial symptoms. Symmetry of the lesions was seen in 100% of patients. There was a signiifcant difference between groups A and B regarding complete resolution of brain stem and putaminal lesions （P= 0.005 andP=0.024, respectively）. If the correct diagnosis and adequate treatment are not established less than 24 months after onset of the symptoms, irreversible lesions in the brain parenchyma could be ex-pected. Signal abnormalities on magnetic resonance imaging might therefore, at least in the early stages, represent reversible myelinolisis or cytotoxic edema associated with copper toxicity.     

肝脏铁过载的评估及治疗新进展

铁过载为铁在体内过度沉积并导致肝脏、胰腺、心脏、内分泌器官等结构损害和功能障碍的一种病理状态。肝脏为机体储存铁的主要部位,过度铁沉积可诱发肝内炎症及纤维组织增生,后期可发展为肝硬化,甚至肝癌,影响预后。正确的评估及有效的治疗可在一定程度上改善铁过载引起的肝组织损伤,提高患者生存率。     

Biological mercury measurements before and after administration of a chelator (DMPS) and subjective symptoms allegedly due to amalgam

The aim of the study was to explore multivariately the relationship between subjective symptoms allegedly due to amalgam and mercury measurements before and after administration of a chelator. Of 120 participants, the mercury concentrations in urine (U-Hg) and plasma (P-Hg) before and after a chelating agent or placebo were determined as were the numbers of fillings and symptoms allegedly due to subjective symptoms. The dental status was charted. Blood was analysed on 13 parameters. The analysis revealed neither the parameters in blood nor the subjective symptoms to be associated with a dimension dominated by 'mercury indicators'. The final analysis was therefore performed with 'number of subjective symptoms' and enabled to distinguish two subsamples. One subsample was characterised by > 2 subjective "symptoms", highest scores for U-Hg, P-Hg and filled surfaces, and chewing gum for > 1 h a day. The other subsample comprised the subjects with few filled surfaces and low U-Hg and P-Hg, but was not characterised by "no subjective symptoms". The chelator was considered neither to invalidate nor to improve these findings and was concluded not to be helpful in diagnosing "symptoms". The chelator caused side effects in 42% of the subjects and the placebo in 27%. A relationship between amalgam fillings and subjective symptoms could not be shown. Therefore, the mere fact of knowing to have amalgam fillings was assumed to be the reason why subjective symptoms were attributed to amalgam and side effects were ascribed to the treatment.     

Mobilization of Methyl Mercury in Vivo and in Vitro using N–acetyl–DL–penicillamine and other Complexing Agents

Abstract The distribution and excretion of mercury was studied in mice given a single intravenous dose of 5 umol/kg of methyl mercuric chloride. Oral treatment with N–acetyl–DL–penicillamine (3 mmol/kg per day) removed more mercury from the brain and from the whole body than the corresponding treatment with other complexing agents, and it was also effective on delayed treatment. Even more mercury was removed into the faeces and the urine, by higher doses of N–acetyl–DL–penicillamine, and 4 days of treatment with 27 mmol/kg per day of this compound did not give rise to any significant toxic symptoms in the mice. In vitro experiments showed that the chemical affinity of N–acetyl–DL–penicillamine for methyl mercury was higher than that of the other thiols tested, except D–penicillamine. In contrast to the latter, N–acetyl–DL–penicillamine easily penetrated the cellular membranes, and therefore rapidly removed a substantial fraction of methyl mercury from the blood cells. It is assumed that N–acetyl–DL–penicillamine can reduce the mercury concentration in brain cells by converting the intracellularly non–diffusible methyl mercury into a freely diffusible complex.