RESUMO
The aim of the present study was to evaluate the antibacterial behavior of polypyrrole nanoparticles (PPy-NPs) in water against biofilm producer or not S. aureus isolated from cows and goats with mastitis. One hundred and thirty-eight isolates of S. aureus were initially evaluated for bioï¬lm formation by spectrophotometry in microplates. In addition, the minimum inhibition concentration (MIC) and minimum bactericidal concentration (MBC) of PPy-NPs in water for planktonic S. aureus were determined. From the bovine samples analyzed, 5 (4.46%) S. aureus isolates showed a strong biofilm production, 17 (15.18%) moderate production, 36 (32.14%) with weak production and 54 (48.21%) did not produce biofilms. Strains from goats (26) showed no bioï¬lm production in 18 (69.23%) strains and weak bioï¬lm production in 8 (30.76%) strains. The MIC and MBC of S. aureus to PPy-NPs were found in the same concentration (125µÉ¡/mL) in all strains tested, regardless of biofilm production or not. This ï¬nding provides a new insight into the interaction between PPy-NPs and S. aureus, and will offer potential beneï¬ts for the control of mastitis.(AU)
Assuntos
Animais , Feminino , Bovinos , Pirróis/administração & dosagem , Staphylococcus aureus/efeitos dos fármacos , Cabras/microbiologia , Mastite/veterinária , Biofilmes , Antibacterianos/uso terapêuticoRESUMO
Objective To explore the promoting effects of bio-polymer composite film as a micro-skin auto-graft covering on wound healing. Methods The full thickness skin defect models were made on both sides of 30 experimental rabbits. Then, the rabbits were randomly divided into experimental group and control group. In the for-mer group, the side was covered with chitosan/glucomannan composite membrane and in the latter, the side cov-ered with acelluar porcine skin after micro-skin autograft. We obtained wound tissues at week 1 , 2, 3, 4 and 5 af-ter operation. The conditions of wound healing were observed, the rate of wound healing was calculated, HE stain-ing was made, and PCNA and CD31 were detected by immunohistochemistry. Results (1) During 2~4 weeks af-ter operation, the rate of wound healing in the experimental group was significantly higher than that of the control wound (P<0.01). (2) The amount of neutrophil in experimental group was less than that of the control after oper-ation. (3) During 1 ~ 2 weeks after operation, the expression of PCNA in the experimental group was higher than that of the control group (P < 0.01), but lower than the control wounds during 1 ~ 2 weeks after operation (P <0.01). (4) During 1 ~ 5 weeks after operation, the expression of CD31 in the experimental group was higher than that of the control group (P < 0.01). Conclusion Chitosan/glucan-mannan composite membrane as a micro-skin autograft covering may promote wound healing.