Background: Infection of burn wounds by multidrug-resistant (MDR) Pseudomonas aeruginosa (P. aeruginosa) is a leading cause of morbidity and mortality and remains one of the most challenging concerns for the burns unit. The aim of this study is purify and characterize the haemolysin produced by multidrug resistant P. aeruginosa PAO1 isolated from burn wounds. Methods: Isolation and identification of P. aeruginosa from burns was done by standard bacteriological methods. P. aeruginosa PAO1 was identified by PCR amplification and sequencing of the 16S rRNA gene. The haemolysin of P. aeruginosa PAO1 was purified by 70% ammonium sulphate precipitation followed by gel filtration on Sephadex G-100, and separation by SDS-Poly Acrylamide Gel Electrophoresis. In vivo toxicity of the purified haemolysin was determined by intraperitoneal injection of Swiss albino mice, and in vitro toxin-antitoxin neutralization test was performed as previously described. Results: The pure haemolysin had a molecular weight of 37 kDa, with maximum activity at 25°C for 30 minutes and stable within pH range of 4-9 (maximum activity at pH 7). The haemolysin was activated by Ca2+, Fe3+ and Cu2+. Intraperitoneal injection of mice with 0.5ml of haemolysin (128 HU/ml) caused 100% mortality while 0.5 and 0.1 ml of haemolytic titer (64 HU/ml) of the heated haemolysin (toxoid) caused 50% and 0% mortality respectively. In vitro toxin-antitoxin neutralization test revealed that anti-haemolysin antitoxin was present in the serum of the mice that were previously vaccinated with heated toxin. Conclusion: This study concluded that haemolysin can be a potential vaccine component for prevention of haemolysis caused by multidrug resistant P. aeruginosa in burn patients.Keywords: haemolysin, Pseudomonas aeruginosa, multidrug resistant organism
The gross chemical composition, protein content and amino acid composition of mango stone kernels of four Egyptian varieties (Ewsi, Hendi, Fonso and Timour) were investigated. Carbohydrates are the main components of the seed. The protein content varies between 5.0 and 7.2% and the ether extract ranged from 10.8% to 13.6%. High glutamic acid, aspartic acid and leucine content and low concentration of sulfur-containing amino acids are characteristic for the proteins of mango kernels. Lysine level is also low, the concentration of other essential amino acids is acceptable. Sulfur-containing amino acids are the first limiting ones followed by lysine and threonine.
Four strains belonging to the genus Curvularia were tested for their ability to transform progesterone to cortexolone and hydrocortisone. Curvularia lunata RCMB 019002 showed the greatest bioconversion efficiency (29.64%). In a medium containing (g/l); yeast extract 4 and malt extract 20, the substrate was converted after 48h to cortexolone and cortisol. The maximum bioconversion efficiency (37. 72%) was recorded when phosphate buffer was used at pH 7.0. The transformation pattern of progesterone markedly affected by the inoculum size and culture age. The bioconversion efficiency increased (63.2 %) when the substrate concentration was 5 mg/50ml fermentation medium. The addition of the surface active agents Tween 60 and Tween 80 to the medium at concentrations of 100 µl, 50 µl, respectively increased the bioconversion efficiency (66.70 and 68.64 %, respectively). Among the tested amino acids, L-asparagine enhanced the formation of cortexolone and cortisol.
Introduction: Recurrent otitis externa is a worldwide problem. This study aims to identify the different aetiological organisms isolated from otitis externa and their sensitivity to different antibiotics. Methods: A total of 27 patients with clinical presentation of otitis externa for a period of three weeks or more were enrolled for the study. Two swab samples collected from each infected ear were cultured for bacterial and fungi, and growth identified using standard microbiological methods including analytical profile index (API) system. Antibiotic susceptibility of isolated bacteria was performed by the disk diffusion technique. Results: Thirty one organisms were isolated from the 27 patients; 12 (38.7%) fungi and 19 (61.3%) bacteria species. Aspergillus spp was the most frequently isolated organism (35.4%) while Pseudomonas aeruginosa was the most frequently isolated bacteria (19.3%), and was most sensitive to amikacin. Four of 11 patients with Aspergillus infection showed clinical resistance to econazole local treatment but had complete clinical response to itraconazole oral treatment. Conclusion: Otitis externa in Egypt is caused by antibiotic resistant bacteria or fungi, and the most causative organisms are Aspergillus spp and Ps. aeruginosa.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.