OBJECTIVE: To study the therapeutic effect of Suyuping in which liposome is the main constituent on II degree burn wound. METHODS: From October 1998 to October 1999, 42 cases with II degree burn wound were adopted in this study. Among them, there were 30 males and 12 females, the average wound area was (23.4 +/- 9.7)%. The wounds on the left side of body were managed with sulfadiazine argentum(SD-Ag) while that on the right side with Suyuping. Healing and other situation about the burn wounds were observed and recorded at times. RESULTS: Forty-two patients completely healed when discharged from hospital. The average wound area managed with Suyuping was (11.2 +/- 7.3)% and the area with SD-Ag was (9.4 +/- 5.8)%. The mean healing time of Suyuping group was(18.4 +/- 4.7) days while that of SD-Ag was (23.5 +/- 7.9) days, there was significant difference(P lt; 0.05). Suyuping group presented few wound pain, allergy, bleeding and the side effect was less. CONCLUSION: Suyuping can accelerate wound healing and attenuate wound pain, allergy and bleeding, it is a potential and specific topical agent for treating II degree burn wound.
Objective To investigate the influence of cationic liposomemediated endostatin gene on colorectal cancer liver metastasis. Methods Animal model for colorectal carcinoma liver metastasis were established. The plasmid expressing endostatin genelipofectAMINE were injected in vein. Results After cationic liposomemediated endostatin gene were injected in vein, the incidence of liver metastasis and mean numbers of liver tumors were decreased, survival time of animal was significantly longer. Conclusion Intravenous injection of cationic liposomemediated endostatin gene can control the development of colorectal cancer liver metastasis effectively.
Objective To investigate the possibility of constructing eukaryotic expression vector for human glial derived neurotrophic factor （hGDNF）, transfecting it to spinal cord tissue of rats so as to treat acute spinal cord injury. Methods The eukaryotic expression vector pcDNA3-hGDNF was constructed by recombinant DNA technique, transfected into glial cell and neuron of spinal cord by liposome DOTAP as experimental group. In control group, mixture of empty vector and liposome was injected. The mRNA and protein expressions of hGNDF were detected by RT-PCR and Western blot. Results After the recombinant eukaryotic expression vector for hGDNF was digested with Hind III and XbaⅠ, electrophoresis revealed 400 bp fragment for hGDNF gene and 5 400 bp fragment for pcDNA3 vector. In the transfected spinal cord tissue, the mRNA and protein expressions of hGDNF gene were detected with RT-PCR and Western blot. Conclusion The constructed eukaryotic expression vector pcDNA3hGDNF could be expressed in the transfected spinal cord tissue of rat, so it provide basis for gene therapy of acute spinal cord injury.
Liposomes with precisely controlled composition are usually used as membrane model systems to investigate the fundamental interactions of membrane components under well-defined conditions. Hydration method is the most common method for liposome formation which is found to be influenced by composition of the medium. In this paper, the effects of small alcohol (ethanol) on the hydration of lipid molecules and the formation of liposomes were investigated, as well as its coexistence with sodium chloride. It was found that ethanol showed the opposite effect to that of sodium chloride on the hydration of lipid molecules and the formation of liposomes. The presence of ethanol promoted the formation of liposomes within a certain range of ethanol content, but that of sodium chloride suppressed the liposome formation. By investigating the fluorescence intensity and continuity of the swelled membranes as a function of contents of ethanol and sodium chloride, it was found that sodium chloride and ethanol showed the additive effect on the hydration of lipid molecules when they coexisted in the medium. The results may provide some reference for the efficient preparation of liposomes.
Objective To observe the inhibition of LipofectamineTM2000 (LF2000)mediated pSUPER recombinant plasmid expressing small interference RNA targeting hypoxia-induced factor (HIF)-1alpha;(pSUPERsiHIF-1alpha;) on retinal neovascularization in mice. Methods pSUPERsiHIF-1alpha; recombinant plasmid was created. Forty-eight (seven-day-old) C57BL/6J mice were randomly divided into a normal group, the control group, empty vector group and gene therapy group with 12 mice in each group. Mice in the normal group were kept in normal room air, while the other three groups retinal neovascularization was induced by hypoxia. The mice in control group were not treated. The mice in the vector group received intravitreous injection of pSUPER and LF2000 (1 mu;l), and the gene therapy group received pSUPERsiHIF-1alpha; and LF2000 (1 mu;l)one day before being returned to normal room air．Fluorescent angiography was used to assess the vascular pattern. The proliferative neovascular response was quantified by counting the nuclei of new vessels extending from the retina into the vitreous in cross-sections．HIF-lalpha;and vascular endothelial growth factor (VEGF) levels in retinas were measured by immune histochemical staining method and reverse transeriptase-polymerase chain reaction (RT-PCR). Results Fluorescent angiography showed radial branching pattern vessels in the normal group and distorted large vessels, obstructed capillaries, many neovascular tuffs, fluorescence leakage in the peripheral retina in the control group and vector group. The gene therapy group demonstrated a significant reduction in neovascular tufts and fluorescence leakage compared with the control group and the vector group. The number of vascular cell nuclei extending breaking through the internal limiting membrane(ILM) of control group and vector group increased significantly compared with normal group (F=5850.016,P＜0.05), while obviously decreasing in the gene therapy group compared with control group (F=3012.469,P＜0.05). Immunohistochemical staining showed the expression of HIF-1alpha; protein in nucleus and VEGF protein in cytoplasm. The expression of HIF-1alpha; protein in retina was negative, while VEGF protein was weakly positive in normal group. The expression of HIF-1alpha; and VEGF protein were both positive in control group and vector group, while weakly positive in gene therapy group. The Results of RT-PCR showed that the expression of HIF-1alpha; mRNA in retina was increased significantly in control group and vector group as compared with normal group (F=3102.326,P＜0.05), while decreasing significantly in gene therapy group as compared with control group (F=3336.425,P＜0.05). Conclusion Retinal neovascularization in the mice is significantly inhibited by intravitreal injection of LF2000-mediated recombinant plasmid pSUPERsiHIF-1alpha;.
ObjectiveTo study the effect of Triton X-100 promoting liposome-mediated bone morphogenetic protein 2 (BMP-2) gene transfection of rat bone marrow mesenchymal stem cells (BMSCs). MethodsBMSCs were separated and cultured from the femur and tibia of healthy Wistar rats (8-week-old, male). The 3rd passage BMSCs identified by detecting the surface antigen were used to transfect. The optimum concentration of Triton X-100 for liposome mediated gene transfection was determined with ELISA meter by the way of MTT. In optimum concentration of Triton X-100, liposome mediated BMP-2 gene was transfected to BMSCs. The experiment was divided into 3 groups according to types of trasfection agents:BMSCs were transfected with Triton X-100+liposome+BMP-2 (experimental group), with liposome+ BMP-2 (conventional transfection group), and untransfected BMSCs served as blank control group. After 48 hours of transfecting, the green fluorescent protein (GFP) in cells was detected through inverted fluorescence microscope. After 72 hours of transfection, real-time fluorescence quantitative PCR was applied to measure the mRNA expression of BMP-2. Results0.01% Triton X-100 was determined to be the optimum concentration for not only making the BMSCs maintain vitality, but also achieving a certain effect on BMSCs. After trasfecting for 48 hours, GFP was observed through inverted fluorescence microscope in the experimental group and conventional transfection group, but was not observed in the blank control group. After trasfecting for 72 hours, the relative BMP-2 mRNA expression level was 5.94±0.12 in the experimental group, and was 4.99±0.08 in the conventional transfection group, showing significant difference (t=360.28, P=0.02). The transfection efficiency was increased by 19% in the experimental group. Conclusion0.010%Triton X-100 can promote the liposome mediated BMP-2 gene transfection of rat BMSCs, and can improve the transfection efficiency.
Objective To reviewe the research progress of liposomes as antibiotic carriers. Methods Domestic and abroad literature concerning liposomes as antibiotic carriers was reviewed and analyzed thoroughly. Results Liposomes as antibiotic carriers can significantly improve drug distribution, enhance antibacterial activity, and reduce the side effects of antibiotics during treatment. But it also has some problems, such as poor physical and chemical stabilities and low encapsulation efficiency. Conclusion Liposomes as antibiotic carriers can reduce the drug toxicity, improve drug biodistribution, and pharmacokinetics, and bring the dawn to completely curing infections disease.
Microvesicles (MVs) is small membrane vesicles released from different cell types under different conditions. Studies have shown that MVs may mediate vascular inflammation, angiogenesis, and other pathological processes. MVs may play an important role in the pathogenesis of diabetic retinopathy (DR) by mediating endothelial cell injury, thrombosis and neovascularization. The plasma MV level may be an effective parameter to monitor the development of DR. This article will summarize the research progress of the relationship between MVs and DR in recent years.
Objective To investigate the inhibitory effect of proliferation cell nuclear antigen (PCNA) antisense oligonucleotides mediated by liposome transfection on hepatocellular carcinoma cell proliferation. MethodsThe antisense oligonucleotides were complementary to 18mer sequences next to the start codon of PCNA mRNA sequences. The human hepatocellular carcinoma cell line Bel7404 was treated with antisense oligonucleotides. The inhibition of proliferation was estimated by MTT method. We compared the deference between the liposome mediated transfection technique and direct transfection technique. ResultsThe cell proliferation was inhibited effectively by antisense oligonucleotides. A sense sequence oligomer showed no effect.Liposome mediated transfection could enhance the inhibitory effect. Conclusion Liposome mediated transfection could enhance the inhibitory effect of PCNA antisense oligonucleotides on hepatocellular carcinoma cell proliferation.
Liposome is an ideal drug carrier with many advantages such as excellent biocompatibility, non-immunogenicity, and easy functionalization, and has been used for the clinical treatment of many diseases including tumors. For the treatment of tumors, liposome has some passive targeting capability, but the passive targeting effect alone is very limited in improving the drug enrichment in tumor tissues, and active targeting is an effective strategy to improve the drug enrichment. Therefore, active targeting liposome drug-carriers have been extensively studied for decades. In this paper, we review the research progresses on active targeting liposome drug-carriers based on the specific binding of the carriers to the surface of tumor cells, and summarize the opportunities, challenges and future prospects in this field.