Nanotechnology for colorectal cancer detection and treatment

Colorectal cancer (CRC) is the third most diagnosed cancer and the second leading cause of cancer-related mortality in the United States. Across the globe, people in the age group older than 50 are at a higher risk of CRC. Genetic and environmental risk factors play a significant role in the development of CRC. If detected early, CRC is preventable and treatable. Currently, available screening methods and therapies for CRC treatment reduce the incidence rate among the population, but the micrometastasis of cancer may lead to recurrence. Therefore, the challenge is to develop an alternative therapy to overcome this complication. Nanotechnology plays a vital role in cancer treatment and offers targeted chemotherapies directly and selectively to cancer cells, with enhanced therapeutic efficacy. Additionally, nanotechnology elevates the chances of patient survival in comparison to traditional chemotherapies. The potential of nanoparticles includes that they may be used simultaneously for diagnosis and treatment. These exciting properties of nanoparticles have enticed researchers worldwide to unveil their use in early CRC detection and as effective treatment. This review discusses contemporary methods of CRC screening and therapies for CRC treatment, while the primary focus is on the theranostic approach of nanotechnology in CRC treatment and its prospects. In addition, this review aims to provide knowledge on the advancement of nanotechnology in CRC and as a starting point for researchers to think about new therapeutic approaches using nanotechnology.     

药物构效关系研究与药物设计中常用计算机软件

分子力学、量子化学和分子图形学是研究有机药物分子电子特性、空间性质及其与受体相互作用的有力工具。现扼要介绍国内外较常用的量子化学和分子力学及分子图形学有关计算机程序的应用特性。     

CVI-Q检测颈动脉血流量的临床应用价值

目的 :用彩色速度显像定量 (CVI Q)技术测定颈动脉血流量并给出青年组正常参考值。方法 :应用传统的多普勒法及CVI Q法对正常 5 0名在校四年级大学生进行左、右颈总动脉血流量的测定比较。结果 :单侧颈总动脉血流量传统法测定为 (789.49± 15 3 .40 )ml·min-1,CVI Q法为 (3 92 .85± 63 .95 )ml·min-1,两者有显著性差异 (P <0 .0 0 1) ,男女之间、左右之间无明显差异 ,S/D、RI和PI 3组数据两两之间亦无显著性差异。结论 :CVI Q是一种实用、无创、简便、可靠的测量方法 ,具有良好的临床应用价值     

Photodynamic therapy of tumours: value of quantum chemical procedures for characterization of new drugs. Prediction of the electronic structure of zinc(II) phthalocyanine with special emphasis on triplet state excitation energies

Zinc(II) phthalocyanine is the active component of the liposomal formulation CGP 55847 which showed a high activity in photodynamic therapy in a variety of animal tumours. The photophysical properties of zinc(II) phthalocyanine have been studied in detail and compared to those of Photofrin, the only sensitizing agent approved so far for phase III/IV clinical trials. Since the efficacy of photodynamic therapy intrinsically depends on the spectroscopic features of the sensitizer, quantum chemical methods have proven to be an efficient means for optimizing chemical structures. As will be shown, a simple modification of the time-honoured INDO model of Pople allows a prediction of the singlet and triplet state properties of molecules of the size of zinc(II) phthalocyanine with an rms error of ≤ 1000 cm⁻¹.     

苯并恶唑类化合物的研究——Ⅰ.化合物的合成及光物理性能

合成了四种结构类型的苯并恶唑化合物共15个:测试了它们的红外吸收光谱,以及它们在DMF中的紫外吸收、荧光发射和激光发射光谱。苯基取代物的荧光量子产率在0.64～0.66,无激光性能。其余的化合物荧光量子产率都大于0.70,在最大吸收波长下的激光转换效率为2.5～5.9%。     

An algorithm for the automated quantitation of metabolites in in vitro NMR signals.

The quantitation of metabolite concentrations from in vitro NMR spectra is hampered by the sensitivity of peak positions to experimental conditions. The quantitation methods currently available are generally labor intensive and cannot readily be automated. Here, an algorithm is presented for the automatic time domain analysis of high-resolution NMR spectra. The TARQUIN algorithm uses a set of basis functions obtained by quantum mechanical simulation using predetermined parameters. Each basis function is optimized by subdividing it into a set of signals from magnetically equivalent spins and varying the simulated chemical shifts of each of these groups to match the signal undergoing analysis. A novel approach to the standard multidimensional minimization problem is introduced based on evaluating the fit resulting from different permutations of possible chemical shifts, obtained from one-dimensional searches. Results are presented from the analysis of (1)H proton magic angle spinning spectra of cell lines illustrating the robustness of the method in a typical application. Simulation was used to investigate the biggest peak shifts that can be tolerated.     

量子点体外对小鼠腹腔巨噬细胞细胞化学的影响

目的 探讨量子点(QDs)体外对巨噬细胞细胞化学及酶活性的影响.方法 用倒置相差显微镜、荧光显微镜、细胞化学方法,在细胞水平观察QDs对巨噬细胞的生物相容性及对PAS反应、Feulgen反应、ATP酶、酸性磷酸酶(AcP)、碱性磷酸酶(ALP)、α-醋酸萘酚酯酶(ANAE)、琥珀酸脱氢酶(SDH)、乳酸脱氢酶(LDH)活性的影响.结果 3.125mg/L剂量的QDs对巨噬细胞的结构没有影响,但细胞内的细胞化学及酶活性发生了不同的变化,即PAS反应、Feulgen反应、AcP、ALP、ANAE和Mg2 -ATP酶表现为阳性,而SDH、LDH则为阴性.阳性结果中,Feulgen反应、ANAE、ALP和Mg2 -ATP组中QDs组与空白组比较,有统计学意义(P＜0.05),而PAS反应、AcP组中QDs组与空白组比较,无统计学意义(P＞0.05).结论 在细胞学水平上,QDs虽然可以使巨噬细胞内的某些酶发生变化,但不影响其结构及吞噬功能.3.125mg/L剂量的QDs可以很好地应用于生物医学领域标记活细胞,对细胞没有明显的影响.     

生物功能化半导体量子点对活细胞内蛋白质分子可视化的研究进展

半导体量子点(或称半导体纳米微晶体)具有独特的光谱特性和良好的光化学稳定性。通过改变量子点的材料或粒径大小可在同一波长光激发下获得从紫外到近红外(或从蓝色到红色)波长范围内任意点的发射光谱。随着近年来生物亲和性功能化纳米技术的发展,为半导体量子点用于多通道、高通量对活细胞内蛋白质分子直接观察研究这一国际未解决的难题提供了可能。概述了生物功能化半导体量子点在活细胞生理条件对蛋白质分子进行可视化研究的最新进展,评价了其作为荧光探针对活细胞蛋白质分子进行实时动态研究的发展前景。     

HepG2细胞染色体着丝粒点变异的研究

背景与目的:探讨HepG2瘤细胞染色体着丝粒点(Cd)的变异与其非整倍性畸变的关系.材料与方法:用Cd-NOR同步银染分析技术研究HepG2细胞染色体Cd的变异.结果:HepG2细胞染色体Cd缺失率为2.30%、Cd迟滞复制率为1.02%、小Cd率为2.58%、Cd-NOR融合率为0.64%;与正常人胚胎绒毛细胞染色体Cd变异相比较,HepG2细胞染色体Cd缺失、Cd迟滞复制和小Cd升高,而Cd-NOR融合差异无显著性.结论:HepG2细胞染色体非整倍性畸变的途径可能主要涉及Cd缺失、Cd迟滞复制、小Cd.     

量子共振对肿瘤患者维生素C和微量元素硒的研究

目的 :研究恶性肿瘤患者体内维生素C和微量元素硒的水平。方法 :对临床上已确诊为恶性肿瘤患者用量子共振同康信息检测仪检测其体内的维生素C和微量元素硒。结果 :肿瘤患者严重缺乏维生素C和微量元素硒。结论 :肿瘤患者与正常人群相比 ,体内严重缺乏维生素C和微量元素硒。