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Objective To compare the different doses of low-temperature plasma (LTP) on wound healing in BALB/c mice so as to discuss the effects of the optimal dose of low-temperature plasma dealing with wound in mice and the acting mechanism of wound healing.Methods Adoptatmospheric pressure plasma jet discharged by the dielectric barrier was used to treat mouse skin wound.According to the processing time, the wounds were divided into 10s, 20s, 30s, 40s and 50s experimental groups, while naturally healing wounds served as negative controls and the wounds dealt with recombinant human epidermal growth factor served as positive controls.We recorded the wound size every day, observed the histopathological changes, the expression level of type Ⅰ collagen by immunofluorescence, and analyzed the composition of low-temperature plasma jet.Results The wounds with plasma treatment time of 10s, 20s, 30s, and 40s showed significant daily improvement and almost complete closure at days 12, 10, 7, 13, respectively.However, the wounds with plasma treatment time of 50s remained unhealed atday 14.The wounds in positive control group all healed, and the wound healing effect in positive control group could be achieved in 30s group.HE staining and immunofluorescence staining assays showed the optimal result of epidermal cell regeneration, granulation tissue hyperplasia, and collagen deposition in histological aspect at day 7 in 30 s group.The low-temperature plasma jet contained highly reactive free radicals of nitrogen and oxygen, which play an important role in wound healing process.Conclusion Appropriate doses of cold plasma can accelerate wound healing whereas over-doses of plasma can suppress wound healing.The process of wound healing may be related to reactive oxygen and nitrogen species in LTP.
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In this study ,we aim to identify the protein interaction site of microneme protein 2 (MIC2) and aldolase in Toxoplasma gondii .The tryptophan (Trp ,W) at site 767 of carboxyl terminus of MIC2 (MIC2C) was mutated into alanine (Ala ,A) by site-directed mutagenesis to construct plasmid MIC2C W/A/pGEX-4T-1 .The mutant protein GST-MIC2C W/A was expressed in E .coli upon IPTG induction .Glutathione sepharose beads were incubated with GST-MIC2C W/A and GST-MIC2C respectively ,then incubated with tachyzoite lysates ,and bound proteins were eluted using sample buffer .Eluants were resolved by SDS-PAGE and Western blot .A protein band specifically recognized by anti-aldolase antibody was detected in prod-ucts coming from GST pull-down of GST-MIC2C ,but not in pull-down products coming from GST-MIC2C W/A .With muta-tion of MIC2C W767 to A ,MIC2 protein lost the binding ability to aldolase .Tryptophan (W767 ) was the protein interaction site of MIC2 and aldolase in T .gondii .
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ObjectiveTo explore the efficiency of N,N-diethyl-m-toluamide (DEET) with different concentrations in prevention of Schistosoma japonicum infection in mice.MethodsKunming-mice were randomly divided into four groups for the application of the vaseline ointment with different DEET concentrations (0,10%,20% and 30%). After the abdominal skin of the mice were smeared with those DEETs above mentioned and dipped into water for 10,30 min,1,2 h and 4 h, the mice were infected with (505) cercariae respectively. After infected for 6-7 weeks, all of the mice were sacrificed,and by perfusing heart the worms were collected and counted.Worm reduction rates were calculated and the rank sum tests were carried out. ResultsAt the time points of 1,2 and 4 h , the worm reduction rates were 78.34%,63.15% and 40.23% for 10% DEET vaseline ointment, 98.61%,93.37% and 75.74% for 20% DEET vaseline ointment and 100.00%,98.61% and 93.07% for 30% DEET vaseline oinment respectively(H =10.06,10.84,10.80,all P
ABSTRACT
Objective To compare the effica cy of three N,N-diethyl-m-toluamide (DEET) formulations against Schistosoma japonicum infection in mice. Methods Three 10% DEET formulations (DEET isopropanol solution,DEET cr eam and DEET vaseline ointment)were prepared and two experiments, no-dipping or dipping after applying DEET preparation ,were designed. In each experiment, mice were randomly divided into three experiment groups and three control groups . D ifferent DEET preparations were applied in the experiment groups and isopropanol solution, “yumeijing” cream , vaseline ointment were applied in the control g roups, respectively. At different time points after skin application (0.5, 1, 2 , 4 h and 8 h),the mice were infected with (50?5) Schistosoma j apon icum cercariae on the abdominal skin in no dipping experiment. I n dipping experiment,after mice skin were applied and were dipped for 10,30 min, 1 ,2 h and 4 h, respectively, the mice were infected with (50?5) cercariae. Af ter 6-7 weeks ,all the mice were sacrificed and the worms were collected by hea rt perfusion and counted.Worm reduction rates were calculated and rank sum tests w ere carried out. Results In no-dipping experim ent,three DEET formulations provided 100.0% protection in mice at least for 1 h .A t 2 ,4 h and 8 h ,the worm reduction rates were 94.8%,89.9% and 13.3% for DE ET isopropanol solution, 100.0%,97.8% and 50.7% for DEET cream and 100.0%,9 9.0% and 9 8.0% for DEET vaseline oinment, respectively. In dipping experi-ment, given 50.0% wor m reduction rate as efficient in preventing penetration by the cercariae, the e ffective times were 10 min for DEET isopropanol solution,30 min for DEET cream a nd 2 h for DEET vaseline oinment,respectively. Conclusion Three DEET formulations are effectiv e in preventing Schistosoma japonicum infection in mice.DEET vaseline oinment can provide better protection than the other two D EET formulations.