Methodological Studies on Genomic DNA Extraction and Purification from Plant Drug Materials

本文探讨了菊科９种植物和地胆草的４种对口商品药材基因组ＤＮＡ提取与纯化的原理、方法通过对３种常用植物基因组ＤＮＡ提取方法（ＣｓＣｌ梯度超速离心法、ＣＴＡＢＣｓＣｌ梯度超速离心法和ＣＴＡＢ微量提取法）的条件摸索在ＤＮＡ产率、纯度以及提取纯化过程中影响ＰＣＲ扩增因子方面进行比较，认为ＣＴＡＢ微量提取法是植物类药材基因组ＤＮＡ一种比较省时、有效、经济的提取方法     

Targeted-gene silencing of BRAF to interrupt BRAF/MEK/ERK pathway synergized photothermal therapeutics for melanoma using a novel FA-GNR-siBRAF nanosystem

Melanoma is significantly associated with mutant BRAF gene, a suitable target for siRNA-based anti-melanoma therapy. However, a tumor-specific delivery system is a major hurdle for clinical applications. Here, we developed a novel nano-carrier, FA-GNR-siBRAF for safe topical application, which consists of folic acid (FA) as the tumor-targeting moiety, golden nanorods (GNR) providing photothermal capability to kill tumor cells under laser irradiation, and siRNA specifically silencing BRAF (siBRAF). The in vitro and in vivo results revealed that FA-GNR-siBRAF displayed high transfection rates, and subsequently induced remarkable gene knockdown of BRAF, resulting in suppression of melanoma growth due to the interruption of the MEK/ERK pathway. Combinatorial photothermal effects and BRAF knockdown by FA-GNR-siBRAF effectively killed tumor cells through apoptosis, with enhanced efficiency than individual treatments. Therefore, the FA-GNR-siBRAF simultaneously induced BRAF gene silencing and photothermal effects which achieved synergistic efficacy in the treatment of melanoma, paving a new path for developing clinical treatment methods for melanoma.     

泰山白花丹参干叶片高质量DNA的提取

目的为了从富含多酚和多糖的泰山白花丹参干叶片中分离出适用于AFLP分析的高质量基因组DNA。方法比较了4种DNA提取方法,获得了一种以CTAB法为基础的分离高质量完整DNA的简便、快速方法。CTAB-freeBuffer清洗,4倍CTAB抽提和固体PVP和VC防止氧化。结果使用该方法从泰山白花丹参干叶片中分离的DNAA260/A280为1.86,由此法所得的DNA可直接用于AFLP分析。结论该技术可有效地从富含多酚和多糖的药用植物组织中分离出高质量DNA。     

Polyhydroxylated 2-styrylchromones as potent antioxidants

Four polyhydroxylated 2-styrylchromones, structurally related to flavones and cinnamic acid, have been studied. An SC derivative with OH groups only at positions 3' and 4' on the styryl moiety and another SC bearing an additional OH group at position 5 on the benzopyrone ring were more potent inhibitors of the Cu2+-induced peroxidation of LDL than the flavonoid quercetin. Fluorescence and absorption spectroscopies suggested that one LDL particle may bind 40 SC molecules. A pulse radiolysis study in pH 7 buffered micellar solutions of neutral TX100 and positively charged CTAB demonstrated that one-electron oxidation by *Br2-, *O2- and tryptophan radicals (8Trp) depends strongly on the micellar microenvironment. All SCs were readily oxidized by *O2- in CTAB micelles (rate constants: 6-18 x 10(6) M(-1) s(-1)). In TX100 micelles only the SC derivative with OH groups in position 3' and 4' reacted with *O2- (rate constant: 1.1 x 10(6) M(-1)s(-1)). In CTAB, electron transfer to *Trp radicals was observed for all SCs with rate constants > or =3.2 x 10(7) M(-1) s(-1). In TX100 micelles, this reaction occurred solely with the derivative bearing OH groups only at positions 3' and 4'.     

Monoliths with chiral surface functionalization for enantioselective capillary electrochromatography

The state-of-the-art in CEC enantiomer separations with monolithic capillary columns is comprehensively reviewed. The various types of monolithic columns comprising in situ organic polymer monoliths, molecularly imprinted polymer (MIP) monoliths, silica monoliths and monoliths made from particles are discussed with a focus on materials’ synthesis, chemistry and properties as well as column aspects. Monolithic MIP-type porous layer open-tubular (PLOT) columns are treated herein as well. From this survey of the literature, the authors come to the conclusion that monolithic silica capillaries appear to become the preferred column type for CEC enantiomer separations of low-molecular drugs and other chiral pharmaceuticals or chemicals.     

Cationic solid lipid nanoparticles (cSLN): structure, stability and DNA binding capacity correlation studies

Cationic solid lipid nanoparticles (cSLN) are promising lipid nanocarriers for intracellular gene delivery based on well-known and widely accepted materials. cSLN containing single-chained cationic lipid cetyltrimethylammonium bromide were produced by high pressure homogenization and characterized in terms of (a) particle size distribution by photon correlation spectroscopy (PCS) and laser diffractometry (LD), (b) thermal behaviour using differential scanning calorimetry (DSC) and (c) the presence of various polymorphic phases was confirmed by X-ray diffraction (WAXD). SLN composed of Imwitor 900P™ (IMW) showed different pDNA stability and binding capacity in comparison to those of Compritol 888 ATO™ (COM). IMW-SLN, having z-ave = 138-157 nm and d(0.5) = 0.15-0.158 μm could maintain this size for 14 days at room temperature. COM-SLN had z-ave = 334 nm and d(0.5) = 0.42 μm on the day of production and could maintain similar size during 90 days. IMW-SLN revealed improved pDNA binding capacity. We attempted to explain these differences by different interactions between the solid lipid and the tested cationic lipid.     

改良CTAB法提取新疆一枝蒿干叶基因组DNA

目的:从自然干燥的新疆一枝蒿中提取高质量的基因组DNA,为该药材的分子生物学研究提供参考。方法:采用2种改良十六烷基三甲基溴化铵(CTAB)法与常规CTAB法提取新疆一枝蒿中基因组DNA,通过加适量聚乙烯吡咯烷酮(PVP)研磨样本,在核裂解前用细胞核裂解液(STE)洗涤多酚类和多糖类物质,利用95%乙醇室温沉淀DNA等措施。改良CTAB法2与1相比不用液氮研磨样本。通过琼脂糖凝胶电泳、紫外分光光度法和相关序列扩增多态性(SRAP)检测提取DNA的质量。结果:2种改良CTAB法所得DNA质量均优于常规CTAB法,DNA完整性较好,A260 nm/A280 nm在1.8~2.0,多糖类杂质去除较为干净。SRAP检验条带清晰、多态性良好。结论:2种改良CTAB法均适用于高质量新疆一枝蒿干叶基因组DNA的提取,得到的DNA纯度和完整性均较理想,可为后续分子生物学研究提供良好模版。     

Acid-base equilibrium of puerarin in CTAB micelles

Electronic absorption spectra, fluorescence emission spectra, 1HNMR and ab initio quantum calculation are used to study the acid-base equilibrium of puerarin in cetytrimethylammonium bromide (CTAB) micelles with different microstructures and microenvironments. Experiments suggest the microenvironment provided by CTAB micelle cause the acid-base equilibrium of puerarin to move to the deprotonation reaction. The changes in the chemical shifts of the individual groups of protons in CTAB indicate that the location of puerarin changes from the inner to the outer of the CTAB micelles with an increase in puerarin concentration, which enhances the interaction between puerarin and CTAB. The binding of puerarin with CTAB micelle is a spontaneous (deltaG<0) and endothermic process (deltaH<0), and the hydrophobic and electrostatic force is the main driving force for its solubilization.     

Development of innovative paclitaxel-loaded small PLGA nanoparticles: Study of their antiproliferative activity and their molecular interactions on prostatic cancer cells

Taxanes, including paclitaxel, are anti-cancer drugs approved for the treatment of prostate cancer but which have limited clinical application due to their hydrophobicity, their low therapeutic index and the emergence of chemoresistance. These side effects may be avoided through the use of new drug delivery systems such as nanoparticles, and paclitaxel-loaded PLGA nanoparticles up to 200 nm in size have shown encouraging results. As it is known that size affects the tissular penetration and distribution of tumors via the enhanced permeability and retention effect, so nanoparticles smaller than 100 nm are potentially interesting vehicles for improving paclitaxel delivery and efficacy.     

金银花药材脱氧核糖核酸(DNA)提取方法的研究

目的:研究金银花药材总脱氧核糖核酸(DNA)的提取方法。方法:对经典的十六烷基三甲基溴化铵(CTAB)法进行了改良,采用改良的CTAB法提取金银花药材的总DNA,通过紫外吸收、琼脂糖凝胶电泳检测其纯度和浓度。结果:用改良的CTAB法提取的总DNA的OD260/OD280比值在1.76-1.85之间,干药材提取率为89.8-325.4μg/g。结论:用改良CTAB法提取的基因组DNA纯度高,符合分子生物学的要求。