急性粒单和急性单核细胞性白血病的临床和细胞表面标记分析

目的：分析ＡＭＬ－Ｍ４、Ｍ５患者的临床和免疫学特征。方法：总结了７５例患者的血液学和临床特征，并用活细胞间接免疫荧光法检测了其中３９例患者的细胞免疫表型，着重分析了ＣＤ７＾＋ＡＭＬ在这二类ＡＭＬ中的发生率、临床特征及预后。结果：这两类白血病的ＨＬＡ－ＤＲ、ＣＤ３８、ＣＤ３４阳性率很高，分别为９１．４３％，８５．１９％和６５．６３％；结论：Ｍ４、Ｍ５这二种亚型有不同于其它ＡＭＬ亚型的临床，血液学和生     

细胞表面分化抗原和胞浆内抗原在急性白血病免疫分型中的应用

目的　探讨细胞表面分化抗原CD117及胞浆内抗原CD79a、CD3、MPO在急性白血病细胞的表达规律及意义。方法　对2001-02~2003 -12哈尔滨医科大学附属第二医院血液科39例初诊急性白血病病人,采用CD45 /SSC双参数散点图设门方法,运用直接免疫荧光技术,进行三色流式细胞术免疫表型分析。结果　双表型急性白血病(BAL)CD117表达率为87. 5%。急性髓系白血病(AML)CD117表达率为88%、cMPO表达率为70%,cCD79a及cCD3 在AML中未见表达。6例急性淋巴细胞白血病(ALL)中2例B ALL,cCD79a均为阳性,CD117均为阴性; 3例T ALL,cCD3 均为阳性,其中1例CD117阳性; 1例T、B混合型ALL,cCD79a及cCD3 均为阳性,并伴有CD117阳性。结论　检测CD117、cMPO、cCD79a、cCD3 有助于鉴别AML、ALL、与BAL,且采用CD45 /SSC双参数散点图设门方法,能排除骨髓中正常细胞的干扰,并可直接地证明双表型或双克隆型急性白血病。     

急性白血病的免疫标记诊断

急性白血病的免疫标记诊断同济医科大学附属协和医院血液病研究所邹萍近年来由于杂交瘤技术与分子生物学技术的发展，数目众多的单克隆抗体（ＭｃＡｂ）相继问世。为细胞表面抗原的研究、急性白血病、淋巴瘤等疾病的免疫标记诊断奠定了基础，免疫标记能够提供正常细胞在演...     

成人急性淋巴细胞白血病的免疫标记诊断与疗效观察

本文报告了65例成人急性淋巴细胞白血病的免疫标记诊断结果。按其表面抗原的表达,分为4个亚型:C-,T-,N-,B-ALL。发病情况依次为43.1%,29.20%,15.4%,12.3%。观察了本组各亚型临床治疗疗效,以B-ALL的CR率最低,难治性病例最多。作者认为,急性白血病的免疫表型分析,有助于诊断和预后判断。应根据免疫分型诊断,调整B-ALL化疗方案;可改善B-ALL的预后。     

儿童急性白血病形态学免疫学和细胞遗传学的分型诊断

目的：准确地进行儿童急性白血病（AL）的诊断分型,提高初诊患儿的诊断符合率。方法：采用形态学、免疫学和细胞遗传学（MIC）相结合的诊断方法,分析了110例初诊为AL的患儿。结果：形态学与MIC分型诊断符合率为88．2％;急性淋巴细胞性白血病（ALL）免疫分型诊断符合率为92．2％;而急性髓细胞性白血病（AML）仅为62．9％。8／35例AML表达淋系抗原（1y^ -AML),12／59例ALL表达髓系抗原（My^ -AML);11／110例为杂合性白血病。染色体核型异常检出率为63．6％。t(8;21）易位见于（13／21例）M2;t(7;11）易位见于12例M2;t（15;17）易位见于（2／5例）M3;t（9;22）和t（4;11）易位见于（8／64例）ALL。结论：运用MIC诊断分型方法能提高儿童AL的诊断率,为AL个体化治疗和评估预后提供信息。     

老年人急性白血病免疫表型的特点

目的探讨老年人急性白血病的免疫表型特点。方法采用碱性磷酸酶－抗碱性磷酸酶（ＡＰＡＡＰ）免疫酶法，选用一组单克隆抗体分析５６例老年急性白血病患者骨髓细胞免疫标记。结果显示有３种免疫表型：纯系免疫表型，占８０．４％；多系免疫表型，占１２．５％，绝大多数为急性非淋巴细胞白血病（ＡＮＬＬ）；“裸型”，占７．１％。结论老年人急性白血病细胞更多地起源于造血干细胞的早期分化阶段。     

急性淋巴细胞白血病免疫分型的特点及其临床意义

目的:为了探讨急性淋巴细胞白血病(ALL)各亚型免疫分型的特点及其临床意义。方法:采用CD45/SSC双参数散点图设门,应用三色流式细胞术,对81 例ALL的初诊患者骨髓标本进行免疫分型,并对其中45例进行核型分析。结果:①B细胞系列的ALL(B ALL)中CD19表达最常见(阳性率为100%),而T细胞系列的ALL(T ALL)中CD5和CD7表达阳性率最高,均为90%;B -ALL和T- ALL都存在抗原交叉表达的现象;两组患者的完全缓解(CR)率差异无统计学意义(P>0.05);②伴髓系抗原表达的急性淋巴细胞白血病(My+ALL)比较常见,本组达到39.5%,常累及B淋巴系统(占My+ ALL的84.4%);各髓系抗原中以CD13 表达阳性率最高;此类患者的CR率较高,儿童CR率为72.2%,成人为78.6%;③急性杂合性白血病(HAL)的发病率为19.8%,以髓系、B系共同表达者居多;并且CD34表达阳性率较高(81.3%),该类患者CR率较低(儿童和成人分别为50%和40%);④CD34在B ALL,My+ALL和HAL中表达阳性率较高,而T ALL中少见(P<0.05)。结论:免疫分型在诊断特殊类型的ALL(如HAL,My+ALL)中具有显著优势;CD19和CD5诊断B- ALL和T- ALL的灵敏度较好,但特异性不高,存在抗原交叉表达;CD34和髓系抗原的表达与CR率无相关性,但在HAL,CD34的表达与CR率成负相关。     

小儿急性白血病形态学、免疫学及细胞遗学分型的临床意义

近年来,我们对３５例初治急性白血病（ＡＬ）患儿进行了形态学、免疫学及细胞遗传学检查,现报告如下。　　　　资料与方法：本组初治小儿ＡＬ３５例,男２５例．女１０例;年龄６个月至１７岁。取其初发病时的骨髓进行形态学分型（按ＦＡＢ标准）、免疫学分型（用流式细胞仪间接或直接免疫荧光法检测ＨＬＡ－ＤＲ、ＣＤ２、ＣＤ３、ＣＤ７、ＣＤ１０、ＣＤ１９、ＣＤ２２、ＣＤ１３、ＣＤ３３、ＣＤ１４、ＣＤ６１和　ＣＤ４１单克隆抗体反应．Ｔ细胞系阳性细胞＞３０％为阳性反应,其余以阳性细胞＞２０％为阳性反应）及细胞遗传学分型…     

Halogen bonds in biological molecules

Short oxygen-halogen interactions have been known in organic chemistry since the 1950s and recently have been exploited in the design of supramolecular assemblies. The present survey of protein and nucleic acid structures reveals similar halogen bonds as potentially stabilizing inter- and intramolecular interactions that can affect ligand binding and molecular folding. A halogen bond in biomolecules can be defined as a short C-X...O-Y interaction (C-X is a carbon-bonded chlorine, bromine, or iodine, and O-Y is a carbonyl, hydroxyl, charged carboxylate, or phosphate group), where the X...O distance is less than or equal to the sums of the respective van der Waals radii (3.27 A for Cl...O, 3.37 A for Br...O, and 3.50 A for I...O) and can conform to the geometry seen in small molecules, with the C-X...O angle approximately 165 degrees (consistent with a strong directional polarization of the halogen) and the X...O-Y angle approximately 120 degrees . Alternative geometries can be imposed by the more complex environment found in biomolecules, depending on which of the two types of donor systems are involved in the interaction: (i) the lone pair electrons of oxygen (and, to a lesser extent, nitrogen and sulfur) atoms or (ii) the delocalized pi -electrons of peptide bonds or carboxylate or amide groups. Thus, the specific geometry and diversity of the interacting partners of halogen bonds offer new and versatile tools for the design of ligands as drugs and materials in nanotechnology.     

Anti-Arrhenius cleavage of covalent bonds in bottlebrush macromolecules on substrate

Spontaneous degradation of bottlebrush macromolecules on aqueous substrates was monitored by atomic force microscopy. Scission of C─C covalent bonds in the brush backbone occurred due to steric repulsion between the adsorbed side chains, which generated bond tension on the order of several nano-Newtons. Unlike conventional chemical reactions, the rate of bond scission was shown to decrease with temperature. This apparent anti-Arrhenius behavior was caused by a decrease in the surface energy of the underlying substrate upon heating, which results in a corresponding decrease of bond tension in the adsorbed macromolecules. Even though the tension dropped minimally from 2.16 to 1.89 nN, this was sufficient to overpower the increase in the thermal energy (k_BT) in the Arrhenius equation. The rate constant of the bond-scission reaction was measured as a function of temperature and surface energy. Fitting the experimental data by a perturbed Morse potential V = V₀(1 - e^-βx)² - fx, we determined the depth and width of the potential to be V₀ = 141 ± 19 kJ/mol and β^-1 = 0.18 ± 0.03 Å, respectively. Whereas the V₀ value is in reasonable agreement with the activation energy E_a = 80–220 kJ/mol of mechanical and thermal degradation of organic polymers, it is significantly lower than the dissociation energy of a C─C bond D_e = 350 kJ/mol. Moreover, the force constant K_x = 2β²V₀ = 1.45 ± 0.36 kN/m of a strained bottlebrush along its backbone is markedly larger than the force constant of a C─C bond K_l = 0.44 kN/m, which is attributed to additional stiffness due to deformation of the side chains.     

Visualizing electron rearrangement in space and time during the transition from a molecule to atoms

Imaging and controlling reactions in molecules and materials at the level of electrons is a grand challenge in science, relevant to our understanding of charge transfer processes in chemistry, physics, and biology, as well as material dynamics. Direct access to the dynamic electron density as electrons are shared or transferred between atoms in a chemical bond would greatly improve our understanding of molecular bonding and structure. Using reaction microscope techniques, we show that we can capture how the entire valence shell electron density in a molecule rearranges, from molecular-like to atomic-like, as a bond breaks. An intense ultrashort laser pulse is used to ionize a bromine molecule at different times during dissociation, and we measure the total ionization signal and the angular distribution of the ionization yield. Using this technique, we can observe density changes over a surprisingly long time and distance, allowing us to see that the electrons do not localize onto the individual Br atoms until the fragments are far apart (∼5.5 Å), in a region where the potential energy curves for the dissociation are nearly degenerate. Our observations agree well with calculations of the strong-field ionization rates of the bromine molecule.     

Thermal modulation of birefringence observed in a crystalline molecular gyrotop

Recently, functional organic materials have been put into practical use. The application of molecular motions has the potential to create new molecule-based materials. For this reason, considerable attention has been focused on the chemistry and properties of molecular machines in which mechanical motions of parts of the molecules are observed. In particular, phenylene rotation in the crystalline state has been investigated using framed molecular gyrotops having a phenylene rotor encased in three long alkyl spokes. In this study, we show thermal modulation of birefringence in a crystal due to the states of dynamic equilibrium of a novel molecular gyrotop. A macrocage molecule having a bridged phenylene rotor was synthesized as a novel molecular gyrotop. Rapid rotation of the phenylene rotor of the molecular gyrotop was confirmed by solid-state (2)H NMR spectroscopy that showed changes in the optical properties of a single crystal, i.e., the thermal modulation of birefringence. These results are the first application of the dynamic states in a crystal causing an optical change. These phenomena were also confirmed by control experiments using a molecular gyrotop with a nonrotating xylene rotor. We anticipate our finding to be a starting point for the creation of a new field of material chemistry that will make use of the dynamic states of molecules.     

Chemical Sensors Based on Molecularly Imprinted Sol-Gel Materials

The sol-gel technique is earning the worldwide attention of researchers in the field of material science, due to its versatility in synthesizing inorganic ceramic materials at mild conditions. High purity, homogeneity, controlled porosity, stable temperature and nanoscale structuring are the most remarkable features offered by this method for generating highly sensitive and selective matrices to incorporate analyte molecules. The crafting of sol-gel sensors through molecular imprinting has put great influence on the development of innovative chemical sensors, which can be seen from the growing number of publications in this field. The review provides a brief overview of sol-gel sensor applications, and discusses the contribution of molecular imprinting in exploring the new world of sensors.     

Advanced Molecular Surveillance of Hepatitis C Virus

Hepatitis C virus (HCV) infection is an important public health problem worldwide. HCV exploits complex molecular mechanisms, which result in a high degree of intrahost genetic heterogeneity. This high degree of variability represents a challenge for the accurate establishment of genetic relatedness between cases and complicates the identification of sources of infection. Tracking HCV infections is crucial for the elucidation of routes of transmission in a variety of settings. Therefore, implementation of HCV advanced molecular surveillance (AMS) is essential for disease control. Accounting for virulence is also important for HCV AMS and both viral and host factors contribute to the disease outcome. Therefore, HCV AMS requires the incorporation of host factors as an integral component of the algorithms used to monitor disease occurrence. Importantly, implementation of comprehensive global databases and data mining are also needed for the proper study of the mechanisms responsible for HCV transmission. Here, we review molecular aspects associated with HCV transmission, as well as the most recent technological advances used for virus and host characterization. Additionally, the cornerstone discoveries that have defined the pathway for viral characterization are presented and the importance of implementing advanced HCV molecular surveillance is highlighted.     

布鲁氏菌分子诊断与分型技术研究进展

布鲁氏菌病是全球最常见的人畜共患病之一。布鲁氏菌病大多是由羊种布鲁菌感染所致,其次是牛种和猪种。在过去的20年里,人类和动物布病的防控已经取得了较大进展。然而,由于其非特异性的临床表现,控制和根除布病仍然面临巨大的挑战。随着20世纪90年代以来分子生物学技术的快速发展,分子生物学检测方法已被国内外用来迅速检测研究布鲁氏菌,同时由于全球数据共享的数据库的建立,使得全球对于布病的研究越来越深入。