OBJECTIVE To determine the characterization,anti-tumor efficacy and pharmacokinetics of bufalin-loaded PEGylated liposomes compared with bufalin entity.METHODS Bufalin-loaded PEGylated liposomes and bufalin-loaded lip...OBJECTIVE To determine the characterization,anti-tumor efficacy and pharmacokinetics of bufalin-loaded PEGylated liposomes compared with bufalin entity.METHODS Bufalin-loaded PEGylated liposomes and bufalin-loaded liposomes were prepared reproducibly with homogeneous particle size by the combination of thin film evaporation method and high pressure homogenization method.The particle size and zeta potential of the liposomes were determined by dynamic light scattering technique.The direct imaging of morphology of liposomes was charactered by transmission electron microscope.The content of bufalin in liposomes was analysed by HPLC method.The entrapment efficiency and the particle size was applied to assess the stability profile,after storage at 4℃ on day 0,7,15,30 and 90.The in-vitro release behaviours of bufalin from liposomes were conducted using dialysis bag technique at 37℃.In-vitro cytotoxicity studies were carried out using MTT[3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide]assay on several kinds of tumor cel lines including SW620,PC-3,MDA-MB-231,A549,U251,U87 and HepG2.In-vivo pharmacokinetic study of bufalin liposomes was evaluated by HPLC method.RESULTS Their mean particle sizes were 127.6 nm and 155.0 nm,mean zeta potentials were 2.24 m V and-18.5 m V,entrapment efficiencies were 76.31%and 78.40%,respectively.In-vitro release profile revealed that the release of bufalin in bufalin-loaded PEGylated liposomes was slower than that of bufalin-loaded liposomes.The cytotoxicity of blank liposomes has been found within acceptable range,whereas bufalin-loaded PEGylated liposomes showed enhanced cytotoxicity to U251 cells compared with bufalin entity.In-vivo pharmacokinetics indicated that bufalinloaded PEGylated liposomes could extend eliminate half-life time of bufalin in plasma in rats.CONCLUSION The results suggested that bufalin-loaded PEGylated liposomes improved the solubility and increased the drug concentration in plasma.展开更多
Liposomes have several advantages over viral vectorsfor gene delivery both in vitro and in vivo. However,few data are available concerning gene transfer intohematopoietic stem cells. In order to explore theefficiency ...Liposomes have several advantages over viral vectorsfor gene delivery both in vitro and in vivo. However,few data are available concerning gene transfer intohematopoietic stem cells. In order to explore theefficiency and the stability of expression of gene transferinto hematopoietic stem cells, we have transduced twomarker genes (Neo^R and Lac Z) co-transfer into humanbone marrow CD34^+ hematopoietic stem cells展开更多
The CDKN2 (MTS1/P16<sup>INK4A</sup>) is believed as atumor suppressor gene. It maps in the human’schromosome gp21. It encodes a p16<sup>INK4A</sup> protein thatis an inhibitor of cyclin-depend...The CDKN2 (MTS1/P16<sup>INK4A</sup>) is believed as atumor suppressor gene. It maps in the human’schromosome gp21. It encodes a p16<sup>INK4A</sup> protein thatis an inhibitor of cyclin-dependent kinase 4. CDKN2gene’s homozygous deletion is common in many tumorderived cell lines. Purpose: We examine展开更多
Five different methods were tested and compared to prepare danofloxacin mesylate liposomes, the ammonium sulfate gradient method with freeze-thawing steps was validated as the best one; the optimal preparation conditi...Five different methods were tested and compared to prepare danofloxacin mesylate liposomes, the ammonium sulfate gradient method with freeze-thawing steps was validated as the best one; the optimal preparation condition confirmed by orthogonal experiment was as follows： EPC-CH ratio was 3 ： 2 and 2.6% SA was added to gain the positive electricity; drug-lipoid was 2 ： 5, the concentration of ammonium sulfate was 250 mmol·L-1, water-oil ratio was 1：5, and they were incubated at 35℃ for 15 min. The prepared liposome products were ivory white semitransparent suspension, the electron microscope appearance was intact and globular or globular-like vesicles with uniformed distribution; the particle size was centralized from 3 to 7 gm, zeta-electric potential valued＋ （15.92＋1.49） mV, pH valued 6.02~0.09; HPLC method was established in quantitative analyses of danofloxacin and reverse dialysis with RP-HPLC method was validated for determination of entrapment efficiency. The entrapment efficiency results were all above 90%. They were stored at 4℃ with satisfied stability. Six months later, the appearance, characters and entrapment efficiency were almost with no change展开更多
Cancer metastasis is the leading cause of death in cancer patients worldwide and one of the major challenges in treating cancer.Circulating tumor cells(CTCs)play a pivotal role in cancer metastasis.However,the content...Cancer metastasis is the leading cause of death in cancer patients worldwide and one of the major challenges in treating cancer.Circulating tumor cells(CTCs)play a pivotal role in cancer metastasis.However,the content of CTCs in peripheral blood is minimal,so the detection of CTCs in real samples is extremely challenging.Therefore,efficient enrichment and early detection of CTCs are essential to achieve timely diagnosis of diseases.In this work,we constructed an innovative and sensitive single-nanoparticle collision electrochemistry(SNCE)biosensor for the detection of MCF-7 cells(human breast cancer cells)by immunomagnetic separation technique and liposome signal amplification strategy.Liposomes embedded with platinum nanoparticles(Pt NPs)were used as signal probes,and homemade gold ultramicroelectrodes(Au UME)were used as the working electrodes.The effective collision between Pt NPs and UME would produce distinguishable step-type current.MCF-7 cells were accurately quantified according to the relationship between cell concentration and collision frequency(the number of step-type currents generated per unit time),realizing highly sensitive and specific detection of MCF-7 cells.The SNCE biosensor has a linear range of 10 cells·mL^(-1)to 10^(5) cells·mL^(-1)with a detection limit as low as 5 cells·mL^(-1).In addition,the successful detection of MCF-7 cells in complex samples showed that the SNCE biosensors have great potential for patient sample detection.展开更多
The development of improved gene transfermethods is a prerequisite for gene therapy to realizeits full potentials. One approach is the design ofplasmid-based delivery system that also termed "self-assembling comp...The development of improved gene transfermethods is a prerequisite for gene therapy to realizeits full potentials. One approach is the design ofplasmid-based delivery system that also termed "self-assembling complexes" such as cationic liposome-DNAcomplex (lipoplex) and protein-DNA complex.Unlike viral vectors, liposome-DNA complexes arenoninfectious, nonimmunogenic and exhibit low展开更多
To evaluate the feasibility of using magnetic iron oxide nanoparticle as wild PTEN gene carrier for transfection in vitro to reverse cisplatin-resistance of A549/CDDP cells, A549/CDDP cells were transfected with the w...To evaluate the feasibility of using magnetic iron oxide nanoparticle as wild PTEN gene carrier for transfection in vitro to reverse cisplatin-resistance of A549/CDDP cells, A549/CDDP cells were transfected with the wild PTEN gene expression plasmid (pGFP-PTEN) by magnetic iron nanoparticle and lipo2000. The transfection efficiency was detected by fluorescence microscope and flow cytometer. The expression levels of PTEN mRNA and protein were detected by reverse transcription polymerase chain reaction (RT-PCR) and immunocytochemistry analysis. The effect of PTEN transfection on cell cycle enhances the sensitivity of A549/CDDP to cisplatin and nanoparticle-mediated transfection has a higher efficiency than that of the liposome-mediated group. The apoptosis level was up-regulated in PTEN transfection group. The magnetic iron oxide nanoparticle could be used as one of the ideal gene carriers for PTEN gene delivery in vitro. PTEN can be an effective target for reversing cisplatin-resistance in lung cancer.展开更多
Factor Ⅷ deficiency or hemophilia A is X-linkedgenetic disorder in human. General treatment of severehemophilia A consists of adiministration of plasma-derived or recombinant clotting factor concentrates. Ithas cause...Factor Ⅷ deficiency or hemophilia A is X-linkedgenetic disorder in human. General treatment of severehemophilia A consists of adiministration of plasma-derived or recombinant clotting factor concentrates. Ithas caused a series of problems, i. e. viral infection andcost too much to use rF Ⅷ. Nowadays, people havedeveloped the retroviral vector and the adcnoviral展开更多
基金Supported by Overall Innovation Plan Projects of Science and Technology of Shaanxi Province in China(2015KTZDSF02-01-02)
文摘OBJECTIVE To determine the characterization,anti-tumor efficacy and pharmacokinetics of bufalin-loaded PEGylated liposomes compared with bufalin entity.METHODS Bufalin-loaded PEGylated liposomes and bufalin-loaded liposomes were prepared reproducibly with homogeneous particle size by the combination of thin film evaporation method and high pressure homogenization method.The particle size and zeta potential of the liposomes were determined by dynamic light scattering technique.The direct imaging of morphology of liposomes was charactered by transmission electron microscope.The content of bufalin in liposomes was analysed by HPLC method.The entrapment efficiency and the particle size was applied to assess the stability profile,after storage at 4℃ on day 0,7,15,30 and 90.The in-vitro release behaviours of bufalin from liposomes were conducted using dialysis bag technique at 37℃.In-vitro cytotoxicity studies were carried out using MTT[3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide]assay on several kinds of tumor cel lines including SW620,PC-3,MDA-MB-231,A549,U251,U87 and HepG2.In-vivo pharmacokinetic study of bufalin liposomes was evaluated by HPLC method.RESULTS Their mean particle sizes were 127.6 nm and 155.0 nm,mean zeta potentials were 2.24 m V and-18.5 m V,entrapment efficiencies were 76.31%and 78.40%,respectively.In-vitro release profile revealed that the release of bufalin in bufalin-loaded PEGylated liposomes was slower than that of bufalin-loaded liposomes.The cytotoxicity of blank liposomes has been found within acceptable range,whereas bufalin-loaded PEGylated liposomes showed enhanced cytotoxicity to U251 cells compared with bufalin entity.In-vivo pharmacokinetics indicated that bufalinloaded PEGylated liposomes could extend eliminate half-life time of bufalin in plasma in rats.CONCLUSION The results suggested that bufalin-loaded PEGylated liposomes improved the solubility and increased the drug concentration in plasma.
文摘Liposomes have several advantages over viral vectorsfor gene delivery both in vitro and in vivo. However,few data are available concerning gene transfer intohematopoietic stem cells. In order to explore theefficiency and the stability of expression of gene transferinto hematopoietic stem cells, we have transduced twomarker genes (Neo^R and Lac Z) co-transfer into humanbone marrow CD34^+ hematopoietic stem cells
文摘The CDKN2 (MTS1/P16<sup>INK4A</sup>) is believed as atumor suppressor gene. It maps in the human’schromosome gp21. It encodes a p16<sup>INK4A</sup> protein thatis an inhibitor of cyclin-dependent kinase 4. CDKN2gene’s homozygous deletion is common in many tumorderived cell lines. Purpose: We examine
基金Supported by Harbin Scientific and Technical Innovation Foundation (RC2007QH002031)
文摘Five different methods were tested and compared to prepare danofloxacin mesylate liposomes, the ammonium sulfate gradient method with freeze-thawing steps was validated as the best one; the optimal preparation condition confirmed by orthogonal experiment was as follows： EPC-CH ratio was 3 ： 2 and 2.6% SA was added to gain the positive electricity; drug-lipoid was 2 ： 5, the concentration of ammonium sulfate was 250 mmol·L-1, water-oil ratio was 1：5, and they were incubated at 35℃ for 15 min. The prepared liposome products were ivory white semitransparent suspension, the electron microscope appearance was intact and globular or globular-like vesicles with uniformed distribution; the particle size was centralized from 3 to 7 gm, zeta-electric potential valued＋ （15.92＋1.49） mV, pH valued 6.02~0.09; HPLC method was established in quantitative analyses of danofloxacin and reverse dialysis with RP-HPLC method was validated for determination of entrapment efficiency. The entrapment efficiency results were all above 90%. They were stored at 4℃ with satisfied stability. Six months later, the appearance, characters and entrapment efficiency were almost with no change
基金supported by the National Natural Science Foundation of China(Nos.22274037,22376055 and 21904032)the Natural Science Foundation of Hubei Province(2022CFB383)。
文摘Cancer metastasis is the leading cause of death in cancer patients worldwide and one of the major challenges in treating cancer.Circulating tumor cells(CTCs)play a pivotal role in cancer metastasis.However,the content of CTCs in peripheral blood is minimal,so the detection of CTCs in real samples is extremely challenging.Therefore,efficient enrichment and early detection of CTCs are essential to achieve timely diagnosis of diseases.In this work,we constructed an innovative and sensitive single-nanoparticle collision electrochemistry(SNCE)biosensor for the detection of MCF-7 cells(human breast cancer cells)by immunomagnetic separation technique and liposome signal amplification strategy.Liposomes embedded with platinum nanoparticles(Pt NPs)were used as signal probes,and homemade gold ultramicroelectrodes(Au UME)were used as the working electrodes.The effective collision between Pt NPs and UME would produce distinguishable step-type current.MCF-7 cells were accurately quantified according to the relationship between cell concentration and collision frequency(the number of step-type currents generated per unit time),realizing highly sensitive and specific detection of MCF-7 cells.The SNCE biosensor has a linear range of 10 cells·mL^(-1)to 10^(5) cells·mL^(-1)with a detection limit as low as 5 cells·mL^(-1).In addition,the successful detection of MCF-7 cells in complex samples showed that the SNCE biosensors have great potential for patient sample detection.
文摘The development of improved gene transfermethods is a prerequisite for gene therapy to realizeits full potentials. One approach is the design ofplasmid-based delivery system that also termed "self-assembling complexes" such as cationic liposome-DNAcomplex (lipoplex) and protein-DNA complex.Unlike viral vectors, liposome-DNA complexes arenoninfectious, nonimmunogenic and exhibit low
基金Project(07JJ3055)supported by the Natural Science Foundation of Hunan Province,China
文摘To evaluate the feasibility of using magnetic iron oxide nanoparticle as wild PTEN gene carrier for transfection in vitro to reverse cisplatin-resistance of A549/CDDP cells, A549/CDDP cells were transfected with the wild PTEN gene expression plasmid (pGFP-PTEN) by magnetic iron nanoparticle and lipo2000. The transfection efficiency was detected by fluorescence microscope and flow cytometer. The expression levels of PTEN mRNA and protein were detected by reverse transcription polymerase chain reaction (RT-PCR) and immunocytochemistry analysis. The effect of PTEN transfection on cell cycle enhances the sensitivity of A549/CDDP to cisplatin and nanoparticle-mediated transfection has a higher efficiency than that of the liposome-mediated group. The apoptosis level was up-regulated in PTEN transfection group. The magnetic iron oxide nanoparticle could be used as one of the ideal gene carriers for PTEN gene delivery in vitro. PTEN can be an effective target for reversing cisplatin-resistance in lung cancer.
文摘Factor Ⅷ deficiency or hemophilia A is X-linkedgenetic disorder in human. General treatment of severehemophilia A consists of adiministration of plasma-derived or recombinant clotting factor concentrates. Ithas caused a series of problems, i. e. viral infection andcost too much to use rF Ⅷ. Nowadays, people havedeveloped the retroviral vector and the adcnoviral
