The identification of serum ligand-binding proteins using immuno-precipitation techniques and autoradiography

The identification of ligand-binding proteins in serum is important for understanding many metabolic pathways and for interpreting clinical measurements. Most techniques presently available lack the facility to identify specific binding proteins. This problem has been overcome by combining the specificity of immunological methods with the sensitivity of radioisotope detection. The methods comprise an adaptation of 2-dimensional immuno-electrophoresis, and radial immunodiffusion, combined with radiolabelled ligands and autoradiography. They have been used to determine the serum binding of calcium, cadmium, thyroxine and the beta blocking drug propranolol. This technique has wide application to other ligand-binding interactions.     

原发性肝癌双介入治疗的临床分析

目的探讨经肝动脉化疗栓塞（TACE）和CT引导下经皮穿刺瘤内注射无水乙醇（PEI）联合（简称“双介入”）治疗中晚期原发性肝癌的疗效。方法167例不能手术切除的中晚期原发性肝癌患者行双介入治疗,观察其疗效及生存率。结果167例患者行双介入治疗后的1、2、3、5年生存率分别为83．2％、76．8％、56．3％、25％。结论“双介入”治疗能有效地延长中晚期原发性肝癌患者生存期,提高病人生存质量,是中晚期肝癌综合治疗中一种有效可行的方法。     

Transfection Efficiency of 25-kDa PEI–Cholesterol Conjugates with Different Levels of Modification

This report describes lipophilic conjugates of 25-kDa polyethylenimine (PEI) designed to provide better vectors for nucleic acid transfection. Conjugation of cholesterol is known both to improve transfection properties of PEIs and to reduce their cytotoxic effect. However, extensive modification would significantly decrease the polymer overall positive charge, resulting in less efficient condensation and poor delivery of nucleic acids into cells. In this study we tried to find the optimal modification extent of the PEI carrier, 25 kDa PEI, with cholesterol. Conjugates of PEI having a different number of cholesterol residues attached to their amines (5–20% of amines were modified) were synthesized. The conjugates were tested in vitro in transfection experiments, which have been carried out in the presence and in the absence of 10% FBS. Transfection efficiency studies were performed using different types of biologically active nucleic acids: single-stranded oligonucleotide, plasmid expressing vector and small interfering RNA duplex, under conditions close to those routinely applied for each type of delivered nucleic acid. PEI–cholesterol conjugates were applied at concentrations below the level at which the cytotoxic activity was observed. Results of this study demonstrate that efficient transfection and lower toxicity of the compounds is achieved at 1% modification of amino groups of the polymer.     

Inositol based non-viral vectors for transgene expression in human cervical carcinoma and hepatoma cell lines

Myo-Inositol (INO) is a biomolecule with crucial functions in many aspects. In this study, hyperbranched copolymers for gene delivery were synthesized based on inositol and low molecular weight polyethylenimine. The capacity of INO-PEIs to load plasmid DNA and their biocompatibility was demonstrated. A tumor target ligand, folic acid (FA), which was widely used for drug delivery systems, was subsequently conjugated to INO-PEIs and resulted in INO-PEI-FA copolymers. The polymers were then evaluated on their activity to mediate transgene expression in mammalian cell lines. As indicated, INO-PEIs were able to mediate efficient transgene expression, which was particularly noticeable in carcinoma cell line HeLa. INO-PEI-FA further improved the efficiency in HepG2. Distribution of INO-PEI-FA polymers in non-carcinoma NIH 3T3 and carcinoma HeLa cell lines was discussed.     

In vitro Studies on Binding and Release of Vascular Endothelial Growth Factor in Heparinized Bovine Pericardiums

Objective: To investigate binding and release of vascular endothelial growth factor (VEGF) and its effect on adhesion and proliferation of endothelial cells (Ecs)in acellular fresh specimens of bovine pericardiums,which were modified by heparinization.Methods:Cross-linked acellular fresh specimens of bovine pericardiums were heparinized by three methods:(1) heparinized N-(3-dimethylaminopropyl)-N'-ethylcarbodiimide hydrochloride (EDC) treated acellular tissue samples;(2) heparinized poly(ethyleneimine)(PEI) treated acellular tissue samples;(3) heparinized EDC-PEI treated acellular tissue samples.Controlled release of VEGF and its effect on adhesion and proliferation of Ecs was evaluated.Results:In the present study,binding and release of VEGF had better performance in heparinized EDC-PEI treated group,compared with heparinized EDC-alone treated group and heparinized PEI -alone group.We could observe enhanced ability to adhesion and proliferation via modest moisture and effective controlled binding and release of VEGF.Conclusion:Binding of VEGF in heparinized EDC treated group was stable,while Exeiease of VEGF in heparinized treated group was adjusted freely.Interestingly,controlled binding and release of VEGF could exert beneficial effect on adhesion and proliferation of Ecs in heparinized EDC-PEI treated group.     

Synthetic double-stranded RNA oligonucleotides are immunostimulatory for chicken spleen cells

Toll-like receptors (TLRs) are an integral part of the innate immune system that recognize microbe-derived molecular patterns and initiate innate and adaptive defenses against invading pathogens. TLR3 and TLR7 are involved in sensing virus-associated single-stranded and double-stranded RNA (dsRNA) molecules in cellular endosomes to activate the type I interferon pathway in mammals. Although certain synthetic dsRNA molecules have been identified to show immunostimulation in mammalian cells, very little is known about the ability of these sequences to stimulate avian cells. The current study investigated immunostimulatory properties of four synthetic oligonucleotide sequences using chicken splenocytes. Expression of TLR3 and 7, type I interferons and several other cytokines as well as TLR signaling pathway-related genes at different time points post-stimulation was quantified by real-time PCR. A dose-dependent increase in expression of TLR3 was observed in splenocytes treated with poly-UGUGU (poly-UG) and β-galactosidase dsRNA molecules. TLR3 and TLR7 gene expression was significantly up-regulated upon stimulation with all four dsRNA molecules. Furthermore, in a time course study, a significant increase was noted in the expression of TLR3, TLR7, interferon (IFN)-α, IFN-β, interleukin (IL)-1β, IL-6 as well as 2′,5′-OAS in splenocytes treated with poly-UG. In conclusion, the present study demonstrated the immunostimulatory properties of dsRNA oligonucleotides, especially those that contain a poly-UG motif, in chickens.     

静脉化疗联合经皮穿刺无水酒精肝转移瘤内注射治疗肺癌伴肝转移的疗效

目的:观察静脉化疗联合经皮穿刺无水酒精肝转移瘤内注射(PEI)治疗肺癌伴肝转移的治疗效果.方法:收集70例肺癌伴肝转移患者,分别接受静脉化疗和静脉化疗联合PEI治疗,分析两组患者的近期治疗效果、不良反应发生情况及2年内的生存情况.结果:观察组患者的治疗有效率、无进展生存时间及总生存时间显著高于对照组患者(P＜0.05);观察组患者的不良反应发生率略高于对照组,但无明显差异(P＞0.05).结论:静脉化疗联合PEI可以有效提高肺癌伴肝转移患者的近期疗效和长期生存情况,且其不良反应可耐受,适合在临床进一步推广.