An Experimental Study Of The Effect Of Environment Factors On Staphylococcus. Epidermidis Infection

Objective To evaluate the effect of environment factors on the growth of Staph. epidermidis infection and bacterial biofilm formation.Metheds New Zealand white rabbits were used to establish the animal model of prosthetic infection. The New Zealand white rabbits were randomly divided into4%Sodium Chloride group(n=15)、4%ethanol group(n=15)and control group(n=15).The bacteria were injected with0.1ml4%Sodium Chloride and4%ethanol into the knee of rabbits in experimental group;the rabbits were injected with0.1ml normal saline in the control group.The groups were observed at2,4,6,8and16days, histological observations、scanning electron microscopy and RT-PCRwere used to the changes.Results Histological examination revealed that there all the rabbits observed Inflammatory cell infiltration after4days injection and observed colony after16days injection in4%Sodium Chloride group.After6days injection,all the animal were observed Inflammatory cell infiltration in the4%ethanol group and experimental group.Scanning electrol microscopy found bacteria adhere to the prosthtic surface after4days injection,but the number of bacteria have no difference between the groups(P>0.05).On the day of6,8and16days the number of bacteria had increased significantly in the experimental groups,compared with the control groups.RT-PCR revealed that the expression of icaA mRNA have no difference between the three groups(P>0.05)after2and4days. On the day of6,8and16days,the expression had increased significantly in. the experimental groups,compared with the control groups(P＜.05).The expression in the4%Sodium Chloride group was higher than4%Sodium Chloride group(P＜.05)。Conclusion The environment factors could affect the growth of Staph. epidermidis infection and bacterial biofilm formation。...