水溶性量子点荧光探针用于胃癌细胞相关抗原CA242的检测

基于量子点荧光探针对胃癌细胞相关抗原CA242进行了检测。首先在水溶液中直接合成性能优良的量子点荧光纳米颗粒,并在其表面成功修饰了羊抗小鼠IgG和聚乙二醇,制得功能化的水溶性量子点荧光探针,并利用探针对胃癌细胞相关抗原CA242进行检测,进一步与传统的基于荧光染料标记的免疫荧光分析方法进行了比较。实验结果表明:该功能化的探针能够有效地识别胃癌细胞相关抗原CA242,并且在光稳定性和灵敏度方面都较传统的基于荧光染料标记的免疫荧光分析方法有明显的改善,从而为CA242的相关检测以及胃癌的诊断与愈后判断提供了新的方法。     

癌细胞的分化程度与镁的相关性

我们通过对186例消化道癌(喉、食道、贲门、胃、大肠),15例肺癌的癌组织中Zn、Mg等8种元素的测定,发现:癌细胞的分化程度(癌的恶性程度越高,其细胞分化就越差)只与Mg的含量有相关性,而与其它元素没有相关性.Mg的湿基中位数(μg/g)(下同)为:中分化:86, 低分化:126,未分化:173.r=0.999,样本数(n)分别为:163,102,41;高分化样本数很少(n=5).实验证明,用癌组织中Mg的含量来确定癌细胞的分化程度,常使病理学诊断中所遇到的某些疑难问题获得满意的解决.     

火焰原子吸收法测定癌细胞中的钙、镁、铜等金属元素

采用火焰原子吸收法直接测定一系列(食道、胃)癌细胞及其近旁的正常细胞中的钙、镁、铜等金属含量。结果表明，钙的变异系数为1．83％-4．19％，回收率为99．8％-104．0％；镁的变异系数为0．02％～1．18％，回收率为97．2％-98．5％；铜的变异系数为3．80％-6．68％，回收率为90．5％～99．7％；均得到较满意的结果，具有一定的参考价值。     

稀土元素对人肝癌细胞SMMC-7721增殖的影响

用MTT法研究了14种稀土元素(La，Ce，Pr，Nd，Sm，Eu，Gd，Tb，Dy，Ho，Er，Tm，Yb和Lu)对人肝癌细胞SMMC-7721增殖的影响。他们对肝癌细胞的生长作用可分为3类。其中La^3 、Ce^3 和Eu^3 对肝癌细胞的增殖有剂量依赖性正效应，能够在一定浓度范围内刺激细胞生长；Sm^3 ，Gd^3 ，Ho^3 ，Er^3 ，Yb^3 对肝癌细胞生长的刺激作用没有剂量依赖性特征；而Pr^3 ，Nd^3 ，Tb^3 ，Dy^3 ，Tm^3 和Lu^3 则表现出对肝癌细胞的增殖具有不用程度的抑制。推测14种稀土元素作用方式的不同与他们的原子结构有一定的关系，它们对肝癌细胞的相对增殖率随着原子序数的增加呈现出一定的规律性。     

基于cell-SELEX的核酸适配体-纳米材料复合物用于癌细胞检测研究进展

发展高灵敏、高选择性的癌细胞检测方法是实现癌症的早期诊断和治疗的关键.基于cell-SELEX（指数富集配体系统进化法）新技术筛选出的核酸适配体,因其对癌细胞的高亲和力和高特异性,以及体积小、免疫原性小、易于进行化学修饰等优点,已被广泛应用于癌细胞的检测.此外,核酸适配体与纳米材料,包括金属纳米粒子、量子点、纳米二氧化硅和碳纳米材料等结合后,将会增强其对癌细胞的识别能力.本文综述了近年来基于cell-SELEX技术筛选出的核酸适配体与纳米材料结合所形成的复合物作为新型分子工具用于增强癌细胞识别和检测的研究进展,并对此领域的未来发展作了展望.     

基于聚苯胺纳米纤维复合膜界面构建电化学细胞传感器及其对癌细胞的识别检测

合成了聚苯胺纳米纤维,直径在50～70 nm之间;基于静电作用构建聚苯胺纳米纤维-纳米金复合膜界面,并在此界面上层层组装修饰叶酸分子,构建叶酸功能化传感界面,基于叶酸分子与癌细胞表面过量表达的叶酸受体之间的特异性识别作用,将此传感界面应用于对癌细胞的识别和捕获。结果表明:叶酸功能化传感界面能够特异性识别和捕获叶酸受体过量表达的癌细胞。采用电化学阻抗技术,以HeLa细胞为模型,应用于对癌细胞的识别和检测,细胞在1.0×104～6.4×106cells/mL浓度范围内与阻抗变化值ΔRct呈良好的线性关系;检出限为2000 cells/mL。本方法简单、快速灵敏、重现性和稳定性良好;制备的传感器可以再生使用。     

光固定化藻蓝蛋白对体外肝癌细胞7402的抑制作用

从钝顶螺旋藻中提取、纯化生物活性蛋白－藻蓝蛋白,采用光固定法固定藻蓝蛋白到组织培养聚苯乙烯（ＰＳｔ）基板上,制备生物材料,研究这种新材料对体外肝癌细胞７４０２的抑制作用。实验表明,初始固定化藻蓝蛋白的浓度为２０μｇ／ｅｗｌｌ时,对７４０２细胞的抑制率达到５５％,浓度继续升高,对癌细胞的抑制率反而下降,当藻蓝蛋白浓度高达０．５ｍｇ／ｗｅｌｌ及１ｍｇ／ｗｅｌｌ时抑制率又回升到５５％、６６％,通过显微镜观察到,在固定高浓度蛋白的情况下,组织增减聚苯乙烯表面上的藻蓝蛋白层对肝癌细胞的贴壁生长有一定的阻害作用,可能提高了对癌细胞的抑制率。     

一类新型双有机锗化合物及其生物活性

概要介绍了一类新型双β－羧乙基锗氢氧化物合成，结构及理化性质，重点报道了它们对体外Ｏ２＾－和ＯＨ．自由基的清除活性和抑制人肝癌细胞的作用。     

新型喹唑啉衍生物的设计、合成及体外抗肿瘤活性

为了寻找高效、毒性小的抗肿瘤药物,设计并合成了一系列新型的喹唑啉衍生物,其结构经¹H NMR、 ¹³C NMR、 IR、 MS（ESI）和元素分析表征。采用细胞增殖抑制实验法（MTT法）测定了化合物3a～10c对人盲肠腺癌细胞（HCT-8）、人肝癌细胞（HepG2）、人肺癌细胞（A549） 和人高转移性肝癌细胞（MHCC-97H）的体外抑制活性。结果表明：4-位为氨基苯甲基丙二酸二甲酯时（3a~6c）,化合物的肿瘤抑制作用比其相应水解产物（7a~10c）更强;氨基在苯甲基丙二酸二甲酯间位时,抑制活性明显优于对位取代。其中,5c对HCT-8、 A549及MHCC-97H的抑制活性较显著,IC₅₀值分别为13.613 μmol/L, 13.578 μmol/L和25.804 μmol/L。      

彩色多普勒超声鉴别诊断胃间质瘤的临床作用价值

本文探讨彩色多普勒超声鉴别诊断胃间质瘤的临床价值。选取疑似胃间质瘤患者88例为研究对象,比较胃间质瘤和非胃间质瘤间彩色多普勒超声特征差异。经术后病理学诊断,胃间质瘤63例,非胃间质瘤25例。彩色多普勒超声诊断胃间质瘤的灵敏性、特异性、准确性、阳性预测值和阴性预测值分别为87.30%、84.00%、86.36%、93.22%和72.41%;胃间质瘤肿瘤直径、阻力指数、血流丰富比例和液化比例明显高于非胃间质瘤(P0.05);中危和高危胃间质瘤肿瘤直径和液化比例明显高于极低和低危胃间质瘤(P0.05)。彩色多普勒超声在诊断胃间质瘤中有一定价值。     

二氧化碳和丙烯直接合成甲基丙烯酸的NiPMo/TiO2催化剂的研究

用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%.     

Toward new camptothecins. Part 6: Synthesis of crucial ketones and their use in Friedländer reaction

In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments.     

CoFe2O4自形成磁性液体场致结构化对磁化的影响

The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula.     

Highly regioselective Buchwald–Hartwig amination at C-2 of 2,4-dichloropyridine enabling a novel approach to 2,4-bisanilinopyridine (BAPyd) libraries

The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines.     

KMnO4-mediated oxidative CN bond cleavage of tertiary amines: Synthesis of amides and sulfonamides

KMnO₄-mediated oxidative CN bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields.     

Chemistry of heterocyclic compounds at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences, over 50 years (Review)

The review contains a concise historical account and information on the most significant researches undertaken by the staff at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences on the Chemistry of Heterocyclic Compounds. Dedicated to Academician of the Russian Academy of Sciences B. A. Trofimov on his 70th jubilee. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1443–1502, October, 2008.     

Sulfur-directed metal-free and regiospecific methyl C(sp3)–H imidation of thioanisoles

Regiospecific and direct imidation of the methyl C(sp³)–H bond of thioanisoles is realized under mild and metal-free conditions with N-fluorobis(benzenesulfonyl)imide as an oxidant and nitrogen source. Proposed mechanism suggests that thionium ion intermediates and a Pummerer-type reaction are involved. The imidation has advantages such as high step-economy, excellent functionality tolerance, and regiospecificity, giving structurally diverse imidation products.     

Selective syntheses of 2H-1,3-oxazines and 1H-pyrrol-3(2H)-ones via temperature-dependent Rh(II)-carbenoid-mediated 2H-azirine-ring expansion

The Rh(II)-catalyzed reaction of 2-carbonyl-substituted 2H-azirines with ethyl 2-cyano-2-diazoacetate or 2-diazo-3,3,3-trifluoropropionate provides an easy access to 2H-1,3-oxazines and 1H-pyrrol-3(2H)-ones. These compounds can be selectively prepared from the same starting material using temperature as the only varied parameter. The 2-azabuta-1,3-diene intermediate, a common precursor for both heterocyclic products, isomerizes into 2H-1,3-oxazine under kinetic control, while 1H-pyrrol-3(2H)-one is the sole product of the reaction at elevated temperatures. According to DFT-calculations a one-atom oxazine ring contraction involving ring-opening to a 2-azabuta-1,3-diene intermediate, followed by a 1,5- and 1,2-prototropic shift leads to the consecutive formation of imidoylketene and azomethine ylide, which then further undergo cyclization to the pyrrole derivative.     

Synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives

Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields.