ABSTRACT
Objective To study the effects of using 25 kDa linear and branched PEI to transfer plasmid DNA pEGFP -C1 (pDNA ,encoding the enhanced green fluorescent protein reporter gene ) to the basilar membrane of the C57BL/6 mice cochlea in vitro .Methods L -PEI/pDNA and B -PEI/pDNA polyplexes were generated in 0 .1M phosphate buffer solution (PBS) or 5% glucose solution .Polyplexes were characterized by transmission electron mi-croscopy .Agarose gel retardation assay was used to determine the plasmid binding ability of L -PEI and B -PEI . The toxicity was investigated by MTT assay .The transfection was firstly evaluated in 293T cell line ,and then the appropriate amount of PEI and plasmid were applied for cochlear explant transfection of P4 mice pups .Results Un-der the same condition ,B -PEI had better transfection efficiency than L -PEI ,but its toxicity was also higher . When generated in PBS ,the polyplexes had lower toxicity than in glucose solution .L -PEI-pDNA nanoparticles could transfect the spiral limbus fibrocytes ,some spiral ganglion neurons and supporting cells ,but the efficiency was low .Conclusion L -PEI could be used as the non -viral vector for the transfection of the cultured basilar mem-brane of P4 mice pups ,but it should be modified to reach higher efficiency .
ABSTRACT
OBJECTIVE@#To study the risk factors and interaction of nasal septal perforation (NSP) in rats.@*METHOD@#Animals (n=120) that underwent unilateral nasal obstruction using Merocel nasal packing or gelfoam with/without standard staphylococcus aureus inoculation were observed for the formation of NSP at 2, 3, 5, and 7 days after operation by endoscope system. Following sacrifice at 7 days, the obtained nasal secretions were prepared for bacterial culture. Experimental interventions were compared with normal controls (n=10).@*RESULT@#Perforation of nasal septum was observed in 80% of the animals accepted nasal obstruction using Merocel nasal packing with standard staphylococcus aureus inoculation in 3 days (P 0.05). There was a weak region in anteroinferior nasal septum in rats, which the almost NSPs located in. The position of NSP does not overlap Merocel.@*CONCLUSION@#The interaction of risk factors contributes to NSP. The occurrence of NSP mainly depends on the construction of nasal septum, while dysaemia is also necessary. Obstruction of nasal drainage and infection promote the development of NSP.
Subject(s)
Animals , Male , Rats , Causality , Disease Models, Animal , Nasal Obstruction , Microbiology , Pathology , Nasal Septal Perforation , Nasal Septum , Rats, Sprague-Dawley , Risk Factors , Staphylococcal Infections , PathologyABSTRACT
Objective To observe the effects of herbal compound in reinforcing the kidney for activating blood and arousing consciousness(HCRAA) on the ABR threshold and the expression of neurotrophic factor 3(NT-3) of the cochlea of gentamicin (GM)-induced ototoxic mice.Methods 40 mice were randomly divided into normal group,model group,and high,middle and low concentration HCRAA groups.Normal group received no treatment.The model group and the HCRAA groups were intraperitoneally injected with GM 100mg/kg per day for consecutive 15 days.At the same time,the model group and the HCRAA groups respectively receiveded normal saline and high,middle and low concentration Chinese medical formula decoction at the same dosage by garage for consecutive 20 days.After the experiment,the mice were tested ABR.The expression of NT-3 of the cochlea in mice was detected by western blot.Results HCRAA at high and middle concentration reduced the GM elevated ABR threshold(P＜0.01),and increased the expression of NT-3 in the cochlea(P＜0.01).Conclusion HCRAA may effectively reduce the elevated ABR threshold induced by gentamycin by protecting GM damaged cochlear hair cell and neurons and increasing the expression of NT-3 in the cochlea.