一种快速分离纯化土豆中羧肽酶抑制剂的方法

土豆中含有一种羧肽酶抑制剂（carboxypeptidase inhibitor，CPI），它极有可能成为一种辅助溶栓药物，因此建立一条土豆中CPI的快速分离纯化路线是很有必要的。土豆去皮匀浆后，所得CPI粗提液经离子交换和分子筛层析得到纯品。产品通过放射免疫分析和Lowry法定蛋白，其相对纯度达到89．38％，320g土豆收获19．92mgCPI，回收率达到50％左右，提取周期小于3d，整个工艺路线为CPI的产业化奠定了基础。     

心房肽酶抑制剂研究进展

80年代以来,对心房肽(ANP)的研究取得了可喜成果,不仅从人类心房组织中提取了活性多肽,阐明了其结构和氨基酸排列顺序,并且对ANP在充血性心力衰竭(CHF)、高血压等心血管疾病中的变化及其作用进行了深入研究,人工合成的外源性ANP已开始应用于临床研究,获得了初步成功,但因ANP在体内的半衰期不超过3min,只能静脉给药,不能口服,不便于长期使用,因而限制了该药的推广应用。近年来,在明确了ANP的体内代谢途径之后,英国Pfizer研究中心率先对心房肽酶抑制剂(atriopeptidase inhibitor)进行了研究,本文就目前研究进展作一简述。     

肽脱甲酰基酶抑制剂LBM-415的研究进展

肽脱甲酰基酶（PDF）作为细菌蛋白质合成过程中的关键酶之一，是一种较理想的抗微生物药物作用靶点。随着PDF晶体结构和作用机制的阐明，PDF抑制剂的研究已经成为近年来抗菌领域研究开发的热点。LBM-415（原名NVP—PDF-713）是一种已经进入临床研究的PDF抑制剂，研究表明其对多种病原菌均有显著的抑制活性。现就其合成方法、药理作用、药动学等方面的研究进行综述。     

N-羧烷基二肽型血管紧张素转化酶抑制剂的合成策略

以马来酸依那普利和赖诺普利为例,围绕新手性中心的构建方法,按逆合成分析切断法分类,综述了Ｎ－羧烷基二肽型血管紧张素转化酶抑制剂的合成策略。     

血管肽酶抑制剂的研究进展

目的阐述血管肽酶抑制剂(VPIs)的作用机制、构效关系以及临床研究等方面的进展。方法根据近期对VPIs的作用机制、构效关系以及研究开发现状的25篇相关文献进行整理和归纳。结果与结论数种血管肽酶抑制剂正在进行治疗高血压、心力衰竭等心血管疾病的临床试验。VPIs有望成为新一代治疗高血压和心力衰竭的药物。     

利钠肽及血管肽酶抑制剂的心肾保护作用

血管肽酶抑制剂能恢复内源性血管收缩剂与血管舒张肽的平衡,其与利钠肽用于心肾疾病,能阻止疾病进展和靶器官受损。     

血管肽酶抑制剂奥马帕曲拉在心血管疾病中的应用研究进展

血管肽酶抑制剂是中性内肽酶和血管紧张素转化酶的双重抑制剂，主要用于治疗高血压和心力衰竭。本文就血管肽酶抑制剂奥马帕曲拉的作用机制、基础研究和临床试验等方面进行综述。     

血管肽酶抑制剂的研究与开发

血管肽酶抑制剂(VPIs)能同时抑制血管紧张素转化酶和中性肽链内切酶，从而抑制肾素-血管紧张素-醛固酮系统和钠利尿肽的降解，促进血管舒张和尿钠排泄，发挥降低血压和改善心肾功能的作用。综述VPIs的作用机制及其产品用于高血压和充血性心衰的开发现状。     

马铃薯胃蛋白酶抑制剂的纯化、特性及抑制机理探讨

从马铃薯中纯化一种胃蛋白酶抑制剂并对其特性及抑制机理进行探讨。利用醇沉、超滤、DEAE-52和Mono Q离子交换层析法从马铃薯中纯化得到一种主要成分是蛋白质的单亚基胃蛋白酶抑制剂(PPI),相对分子质量为16 100。该抑制剂热稳定性良好,对胃蛋白酶有很强的抑制作用,半抑制浓度IC50值为26.67μg/mL,抑制类型属于非竞争和竞争混合型抑制模式。据圆二色光谱(CD)研究胃蛋白酶抑制剂与胃蛋白酶作用前后的构象变化推测抑制剂以类似线形分子的形式覆盖到靶酶活性中心附近的区域上,从而阻止酶的活性中心与底物接触。     

水蛭素促尿激酶纤溶作用研究

目的研究水蛭素对尿激酶诱导的纤溶作用的影响,并分析可能的机制。方法采用尿激酶为纤溶激酶,复钙柠檬酸钠抗凝血浆为纤溶酶原来源的体外溶栓模型,通过测定纤溶产物D-D imm er生成量,微孔板分光光度法跟踪纤溶过程,比较水蛭素与肝素对纤溶的影响。运用土豆羧肽酶抑制剂(CPI)对TAFIa的专一性抑制作用,分析水蛭素与肝素对TAFI活化的影响。结果水蛭素组D-D imm er较肝素组高(P<0.01),水蛭素加CPI组较水蛭素组更高(P<0.01);微孔板分光光度法跟踪纤溶过程,肝素组有明显的纤溶停止和血栓再形成倾向,水蛭素组则可观察到明显的溶栓现象,水蛭素加CPI组效果最好。结论对尿激酶诱导的纤溶,水蛭素比肝素有更好的间接促纤溶作用,其原因主要是水蛭素能有效抑制再次血凝的发生,减少了尿激酶和纤溶酶原的短暂性耗竭。在这一过程中,水蛭素不能彻底抑制TAFI活化,表明对TAFI活化的抑制可能不是水蛭素促尿激酶纤溶作用的主要原因。     

Rationally Designed Sulfamides as Glutamate Carboxypeptidase II Inhibitors

Glutamate carboxypeptidase II (GCPII) is a membrane‐bound cell surface peptidase. There is significant interest in the inhibition of GCPII as a means of neuroprotection, while GCPII inhibition as a method to treat prostate cancer remains a topic of further investigation. The key zinc‐binding functional group of the well‐characterized classes of GCPII inhibitors (phosphonates and phosphoramidates) is tetrahedral and negatively charged at neutral pH, while glutamyl urea class of inhibitors possesses a planar and neutral zinc‐binding group. This study explores a new class of GCPII inhibitors, glutamyl sulfamides, which possess a putative net neutral tetrahedral zinc‐binding motif. A small library containing six sulfamides was prepared and evaluated for inhibitory potency against purified GCPII in an enzymatic assay. While most inhibitors have potencies in the micromolar range, one showed promising sub‐micromolar potency, with the optimal inhibitor in this series being aspartyl–glutamyl sulfamide ( 2d ). Lastly, computational docking was used to develop a tentative binding model on how the most potent inhibitors interact with the ligand‐binding site of GCPII.     

人血清、尿W物质放射免疫分析技术的建立

目的建立W物质RIA检测孕龄非孕妇女血清、尿W物质含量。方法采用氯胺T法以125碘化钠标记3,3＇-二碘甲腺氨酸,经分离、纯化、硫酸化得到硫酸化二碘甲腺氨酸(3,3＇-T2S),作为RIA标记抗原。利用W物质与3,3＇-T2S抗体的交叉反应建立RIA。检测31例孕龄妇女血清和尿中W物质浓度,用尿肌酐浓度修正尿W物质浓度。结果由于使用不同抗体,血清、尿RIA灵敏度分别为23.47fmol/L、93.55fmol/L。血清、尿RIA批内变异6.20％、7.43％(均n=6),血清、尿RIA批间变异13.18％、6.％(均n=6)。孕龄妇女血清和尿W物质浓度分别为(0.23+0.13)nmol／L和(&127;79.94±41.49)pmol/mmol肌酐,二者呈正相关(P＜0.05)。结论血清、尿W物质RIA灵敏、稳定,有望成为胎儿先天性甲低筛查的新方法。     

Radioimmunoassay for mitoxantrone,a new antitumor agent

A sensitive and specific radioimmunoassay for mitoxantrone in serum has been developed. The procedure allows direct measurement of mitoxantrone in unextracted serum samples, by using antisera from rabbits immunized with mitoxantrone-BSA antigen. Tritiated mitoxantrone of high specific radioactivity (ca. 15 Ci/mmol) was used as a radio-tracer ligand. The assay allows the detection of as little as 50 pg/ml and the quantitation of 75 pg/ml in 0.5 ml serum samples. Standard curves were linear in the concentration range of 75–2500 pg/ml, at antiserum dilutions of 1:15,000. The assay shows good reproducibility: coefficients of variation of 3–6% were obtained by analyzing five samples/concentration at 75, 100, 250, 500, and 1000 pg/ml. There was no cross reactivity with the major metabolite in human serum, having concentrations of up to 10,000 pg/ml. Serum samples collected at various time intervals from rats dosed intravenously with mitoxantrone (0.5 mg/kg), were analyzed for unchanged mitoxantrone by RIA. The drug concentrations decreased from 32 ng/ml at 0.5 h to 0.45 ng/ml by 24 h after dosing.Mitoxantrone, a dihydroxyanthracenedione derivative (1), is an antitumor agent currently used in clinical trials with very encouraging results, especially in metastatic breast cancer, and low incidence of adverse reactions (2–4). The drug is being administered intravenously at doses up to 14 mg/m². Preliminary pharmacokinetic studies (to be published separately) indicate rapid distribution, followed by slow clearance rates from the tissues.The sensitivity of the currently available (HPLC) methods (5, 6) is of about 5–20 ng/ml in serum. The purpose of this work was to develop a more sensitive method, such as radioimmunoassay, which can be utilized in pharmacokinetic studies to measure mitoxantrone levels in biological fluids, over extended periods of time after dosing.

---

     

Radioimmunoassay of glipizide in human plasma

Summary A simple, sensitive radioimmunoassay has been developed for the direct determination of glipizide in human plasma. Antisera raised in rabbits immunized with a glipizide analogue conjugated to bovine serum albumin were highly specific, the two main metabolites, 3,cis-hydroxycyclohexyl derivative and 4,trans-hydroxycyclohexyl derivative, having cross reactivities of 0.73% and 1.66%, respectively. The method can measure amounts as small as 1 ng/ml. The intra- and inter-assay coefficients of variation lay between 2.98–5.79% and 2.35–8.66%, respectively. The mean recovery of glipizide added to plasma was 99–105% over the range 1–500 ng/ml. The method was employed to determine plasma levels in six subjects after administration of a 5 mg tablet of glipizide. The results were in accordance with those found after administration of the same dose of radiolabelled glipizide to two other subjects.     

甘肃马铃薯凝集素部分理化性质的研究

目的 :研究甘肃马铃薯凝集素的部分理化性质。方法 :采用SephadexG 15 0凝胶过滤法测定马铃薯凝集素 (STL)的分子量 ;加热法测定其热稳定性 ;硫酸 苯酚法测定中性糖含量 ;光谱法测定其紫外、红外光谱特征。结果 :该凝集素分子量为 10 2kD ,含有 48.5 %的中性糖 ,富含天冬氨酸。热稳定性试验表明 ,在 5 0℃以下对热不敏感 ,在 5 0℃以上对热敏感。光谱分析表明 :该凝集素的最大紫外吸收波长为 2 76nm ,在中红外区有三个特征吸收频率 16 40cm-1,3 15 0cm-1和 3 40 0cm-1。结论 :该研究为马铃薯凝集素的进一步研究、开发提供了科学依据。     

人脑脊液,血清髓鞘碱蛋白放射免疫分析检测方法的建立和初步应用

髓鞘碱蛋白（ＭＢＰ）是特异地位于中枢神经系统白质髓鞘上的一种碱性蛋白质。以牛脑ＭＢＰ为抗原，制备了兔抗血清，以＾１２５Ｉ经氯胺－Ｔ法标记ＭＢＰ，建立了灵敏度达２．０μｇ／Ｌ的检测方法。初步应用于神经外科，发现血清和脑脊液中ＭＢＰ的变化与这些疾病的病情变化及预后有密切关系。血清和脑脊液中ＭＢＰ的检测有可能成为反映中枢神经组织损伤的一个有用的指标。     

Discovery of an Anion-Dependent Farnesyltransferase Inhibitor from a Phenotypic Screen

By employing a phenotypic screen, a set of compounds, exemplified by 1, were identified which potentiate the ability of histone deacetylase inhibitor vorinostat to reverse HIV latency. Proteome enrichment followed by quantitative mass spectrometric analysis employing a modified analogue of 1 as affinity bait identified farnesyl transferase (FTase) as the primary interacting protein in cell lysates. This ligand-FTase binding interaction was confirmed via X-ray crystallography and temperature dependent fluorescence studies, despite 1 lacking structural and binding similarity to known FTase inhibitors. Although multiple lines of evidence established the binding interaction, these ligands exhibited minimal inhibitory activity in a cell-free biochemical FTase inhibition assay. Subsequent modification of the biochemical assay by increasing anion concentration demonstrated FTase inhibitory activity in this novel class. We propose 1 binds together with the anion in the active site to inhibit farnesyl transferase. Implications for phenotypic screening deconvolution and HIV reactivation are discussed.     

Inter and Intra Laboratory Variation of Digoxin Radioimmunoassay in Sweden

Abstract Samples from two pools were sent 10 times to 27 laboratories for assay of digoxin. One pool contained digoxin 2.60 nmol/1 in normal plasma (SP); the other was pooled plasma from patients treated with digoxin (PP). Ten radioimmunoassay (RIA) methods were used. The mean of SP assays was 2.59 nmol/1, not significantly different from 2.60 nmol/1. The mean of PP determinations was 2.46 nmol/1. Within each of the 10 assay rounds, the concentrations showed an almost twofold variation and S.D. averaged 0.33 nmol/1 and 0.31 nmol/1 for SP and PP respectively. Significant differences (P<0.001) were found between mean concentrations obtained for the pools at various laboratories (SP range 2.15-2.85 nmol/1; PP range 2.12-2.72 nmol/1). The laboratory means obtained for SP and PP correlated significantly (P<0.001). Nevertheless, significant (P<0.01) variations between laboratories were found also concerning the mean difference between SP and PP concentrations. The interassay SD of the assays differed significantly between laboratories (range 0.05-0.61 nmol/1). Between and within groups of laboratories using the same RIA method and between various types of laboratories, differences were also found concerning both accuracy and precision of the assays. It is concluded that a better control of digoxin assay is needed.