Background: Pseudomonas aeruginosa is an important cause of nosocomial infection and may lead to septicemia and death. We evaluated the immunogenicity of semi-purified exotoxin A from the bacterium in a mouse burn model. Methods: The toxoid was prepared from exotoxin A taken from toxigenic strains of P. aeruginosa (PA 103). 50 mice were immunized with the toxoid, burned with hot metal and infected with 1 × 10⁸ CFU of toxigenic strains of P. aeruginosa (experimental group); 25 non-immunized mice were also burned and infected (control group). The mortality rate and presence of any exotoxin and P. aeruginosa in the sera, liver and spleen were determined. Results: In the experimental group, 2 mice died before the burns were administered and were excluded from the study. The remainder (48 mice) were challenged with a lethal dose of P. aeruginosa and followed for 70 days. 3 of these mice died. Neither P. aeruginosa nor exotoxin A was not detected in the liver, spleen or sera of the surviving mice. The protective efficacy of toxoid vaccination was therefore 93.8%. In the control group, all mice died from bacteremia and septicemia, most (80%) within 6 days, and P. aeruginosa and exotoxin A were isolated from sera, spleen and liver. Conclusion: Active immunization of mice using a semi-purified exotoxin A derived from P. aeruginosa was 93.8% effective at protecting mice from subsequent P. aeruginosa infections in a mouse burn model.

BACKGROUND Burns are still considered one of the most devastating conditions in emergency medicine affecting both genders and all age groups in developed and developing countries, resulting into physical and psychological scars and cause chronic disabilities. This study was performed to determine the healing effect of curcumin on burn wounds in rat. METHODS Seventy female Sprague-Dawley 180-220 g rats were randomly divided into 5 equal groups. Groups of A-C received 0.1, 0.5 and 2% curcumin respectively and Group D, silver sulfadiazine ointment. Group E was considered as control group and received eucerin. After 7, 14 and 21 days of therapy, the animals were sacrificed and burn areas were macroscopically examined and histologically were scored. RESULTS Administration of curcumin resulted into a decrease in size of the burn wounds and a reduction in inflammation after 14th days. Reepithelialization was prominent in groups A-C while more distinguishable in group C. In group C, epidermis exhibited well structured layers without any crusting. There were spindle shaped fibroblasts in fascicular pattern, oriented parallel to the epithelial surface with eosinophilic collagen matrix. CONCLUSION Curcumin as an available and inexpensive herbal was shown be a suitable substitute in healing of burn wounds especially when 2% concentration was applied.

Self-inflicted burns are among the most devastating of all burn injuries with serious physical, psychological, and financial effects on the individual