ABSTRACT
The properties of polyethyleneimine-cholesterol cationic lipopolymer (PEI-Chol) as gene carries and its gene transfer efficiency in vitro with lipid microbubbles were presented in this paper. PEI-Chol lipopolymer was synthesized by linking cholesterol chloroformate to the amino groups of branched poly(ethyleneimine) (PEI) of 1 800. The structure and molecular weight of PEI-Chol were confirmed by IR, 1H NMR and MADI-TOF-MS (matrix-assisted laser desorption/ionization time-of-flight tandem mass spectrometry), respectively. The average molecular weight of PEI-Chol was approximately 2 000. The gene delivery system of bubble/PEI-Chol/DNA was constructed by mixed PEI-Chol/pDNA (N/P 10:1) complexes with lipid microbubbles (2-8 microm) which were prepared by DPPC, DSPE-PEG2000 and perfluoropropane with the reverse phase evaporation technique. pEGFP-Cl (enhanced green fluorescent protein) was used as report gene to investigate the DNA condensing ability of PEI-Chol lipopolymer by agarose gel electrophoresis. And their cytotoxicity and in vitro transfer efficiency of different complexes were compared with each other in A549 and MCF-7. The results indicated PEI-Chol lipopolymer can condense plasmid DNA when N/P ratio upto 4, PEI-Chol complexes and bubble/PEI-Chol/DNA complexes were nontoxic to A549 and MCF-7 when formulated at the N/P ratio of 10/1 as determined by MTT assay. This bubble/PEI-Chol/DNA delivery system provided good transfer efficiency with other desirable characteristics such as against-precipitation of plasma proteins. In conclusion, bubble/PEI-Chol/DNA complex is a novel non-viral gene delivery system.
ABSTRACT
OBJECTIVE:To investigate the anti-viral effects of Tongqiao zhike liquid against influenza A virus in vitro.METHODS:The inhibitive effect of Tongqiao zhike liquid administered by different ways against human influenza A virus(H3N2) in vitro and its time-effect relationship were assayed by crystal violet staining assay with ribavirin as positive control.RESULTS:Tongqiao zhike liquid showed a satisfactory comprehensive inhibitory effect against human influenza A virus as well as its proliferation after viral adsorption.It was found that Tongqiao zhike liquid had a weak effect in preventing viral adsorption and it had no direct antiviral effect.The inhibitory effect of low concentration of Tongqiao zhike liquid against influenza A virus weakened time-dependently,while at high concentration its anti-viral ability remained stable.CONCLUSION:Tongqiao zhike liquid has a satisfactory effect against human influenza A virus in vitro.
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Aim To assess the effect and mechanism of N acetylcysteine (NAC, antioxidant) on nuclear factor ?B (NF ?B) in lung tissue and bronhial alveolar lavage fluid(BALF) of rats undergoing acute and chronic smoking. Methods All Wistar rats were divided randomly into three groups: control group, smoking group and intervention group. The latter two groups were applied to observing NF ?B expression during different periods (1, 2, 7, 14, 60d). Western Blot assay was used to analyze the activation of NF ?B. Results The first and second day the expression of NF ?B in lung tissue ( 36.9 ? 8.1 and 36.9 ? 8.0 )and in BALF( 24.0 ? 6.1 and 21.2 ? 5.8 ) rose significantly comparing with that in the control groups ( 7.3 ? 2.8 and 5.7 ? 2.6 )respectively (P
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Objective To study the anti-viral effects of Lianhua Qingwen Capsule against influenza A virus in vitro.Methods Under different administration modes,the inhibitory effect of Lianhua Qingwen Capsule on human influenza A virus(H3N2)in vitro and its time-effect relationship were assayed by crystal violet staining assay with ribavirin as positive reference drug.Results Lianhua Qingwen Capsule showed a multi-access effect on anti-human influenza A virus,such as comprehensive inhibition effect,prevention effect on virus adsorption,inhibition on virus proliferation after adsorption and direct killing the virus effect,and the median effective concentrations(EC50)in above-mentioned effects were 0.042,0.031,0.051 and 0.050 mg/mL respectively.Among them,the prevention effect on virus adsorption was the strongest.With the expanding actuation duration of the drug,the inhibitory effect of Lianhua Qingwen Capsule against influenza A virus weakened at low concentration,but no change at high concentration(≥0.031 g/mL).Meanwhile,Lianhua Qingwen Capsule can remarkably decrease the infectivity of influenza A virus.Conclusion Lianhua Qingwen Capsule has an obvious effect against human influenza A virus in vitro.