DNA condensation and size effects of DNA condensation agent

Based on the model of the strong correlation of counterions condensed on DNA molecule, by tailoring interaction potential, interduplex spacing and correlation spacing between condensed counterions on DNA molecule and interduplex spacing fluctuation strength, toroidal configuration, rod-like configuration and two-hole configurations are possible. The size effects of counterion structure on the toroidal structure can be detected by this model. The autocorrelation function of the tangent vectors is found as an effective way to detect the structure of toroidal conformations and the generic pathway of the process of DNA condensation. The generic pathway of all of the configurations involves an initial nucleation loop, and the next part of the DNA chain is folded on the top of the initial nucleation loop with different manners, in agreement with the recent experimental results.

Delivery of pOXR1 through an injectable liposomal nanoparticle enhances spinal cord injury regeneration by alleviating oxidative stress

Oxidation resistance 1(OXR1)is regarded as a critical regulator of cellular homeostasis in response to oxidative stress.However,the role of OXR1 in the neuronal response to spinal cord injury(SCI)remains undefined.On the other hand,gene therapy for SCI has shown limited success to date due in part to the poor utility of conventional gene vectors.In this study,we evaluated the function of OXR1 in SCI and developed an available carrier for delivering the OXR1 plasmid(pOXR1).We found that OXR1 expression is remarkably increased after SCI and that this regulation is protective after SCI.Meanwhile,we assembled cationic nanoparticles with vitamin E succinate-graftedε-polylysine(VES-g-PLL)(Nps).The pOXR1 was precompressed with Nps and then encapsulated into cationic liposomes.The particle size of pOXR1 was compressed to 58 nm,which suggests that pOXR1 can be encapsulated inside liposomes with high encapsulation efficiency and stability to enhance the transfection efficiency.The agarose gel results indicated that Nps-pOXR1-Lip eliminated the degradation of DNA by DNase I and maintained its activity,and the cytotoxicity results indicated that pOXR1 was successfully transported into cells and exhibited lower cytotoxicity.Finally,Nps-pOXR1-Lip promoted functional recovery by alleviating neuronal apoptosis,attenuating oxidative stress and inhibiting inflammation.Therefore,our study provides considerable evidence that OXR1 is a beneficial factor in resistance to SCI and that Nps-Lip-pOXR1 exerts therapeutic effects in acute traumatic SCI.