الفهرس | Only 14 pages are availabe for public view |
Abstract eolytic activity: Summary ………………………………………………………………………………………................ 151 Summary Ps. aeruginosa is worldwide distribution and multiplies freely in animate environment. It causes wide variety of specific infection in man and other vertebrates such as infection of skin, wounds, and abscesses in the internal organs and may give rise to acute septicemic infections Ps. aeruginosa infection has become increasingly prevalent in hospitalized patients with underlying primary disease. It is also will documented that persons undergoing surgical procedures, inhalation therapy ,chemotherapy ,urinary catheterization and other hospitals techniques are predisposed to ps .aeruginosa colonization. Pathogenicity of Ps. aeruginosa might be attributed to various extracellular products such as protease, lecithinase, haemolysins & Exotoxin. Ps.aeruginosa was highly resistant to most of the commonly used antimicrobial agents that inhibit many other bacteria so the treatment of its infection has become important priority in hospitals The aim of this work was isolation and identification of Pseudomonas aeruginosa from different clinical sources and clinical study some pseudomonal products with special attention to virulence factors and to evaluate available anti-pseudomonal drugs. Summary ………………………………………………………………………………………................ 152 A total of 700 clinical isolates from different specimens including urine, burn, wound in Public Ismailia Hospital. In this investigation 109 isolates of genus Pseudomonas were isolated from urine and wound of some patients. (19) Individuals of Ps. aeruginosa were detected and identified from (109) individuals of genus Pseudomonas. The rate of counts and percentages of Pseudomonas aeruginosa were represented by 19 isolates (17.5%) through 109 isolates. Therefore these members (19) of Ps. aeruginosa were chosen for further study (Proteolytic activity, Biofilm formation, Antibiotic susceptibility, Exotoxin A, Molecular study). The highly most proteolytic activity (Ps. a- U 259) that had (25 mm) diameter of clearing zone was chosen for detect the effect of some cultural forces on proteolytic activities. Then we detect the biofilm formations of all Ps. aeruginosa (19) by both methods CAR, STM, and showed that (19) isolates formed biofilm, therefore they had a pathogenic activity. In present study 10 of common and available of different types of antimicrobial agents were used in treatment of ps. aeruginosa ,Susceptibility test of Ps.aeruginosa to various antibiotic showed that Imipenem was the most active antimicrobial agent. All Ps. aeruginosa (19) strains were susceptible (100%) to Imipenem. The studied organisms were sensitive (susceptible) to Ciprofloxacin, Aztreonam, Summary ………………………………………………………………………………………................ 153 Chloramphenicol, Gentamycin, Tetracycline, Trimethoprim, Ampicilline and Ceftazidine .Ps.aeruginosa organisms were multi drug resistant in this study. PCR was used to detect Ps.aeruginosa from clinical samples of the exotoxin A (ETA) structural gene sequence, representing positive pattern to exotoxin A (EXTA) in (16) isolates but negative in (3) isolates. At the end we found that (Ps.a.U-259) isolate had the most potent proteolytic activity, resistant to about 60% of tested antibiotics and had exotoxin A. In the present study was aimed to detect and study the factors affecting on the proteolytic activity of the most potent isolate (U-259) in this activity by the study the effect of: 1- Temp.: where the result shows that the optimum temperature for proteolytic activity was 37 C° and maximum diameter of clearing zone by ps. aeruginosa was obtained within 48 hrs incubation period. 2- Effect of pH value (5.0 to 9.0) by Citrate phosphate buffer, phosphate buffer and boric acid ( borax buffer ) were used to cover this range, maximum diameter of clearing zone of proteolytic activity of Ps.aeruginosa was (22mm) in the presence of phosphate buffer at pH 7.0 Proteolytic activity was found to sensitive to change in pH on either sides of optimum. Summary ………………………………………………………………………………………................ 154 3- Effect of different carbon sources with optimum conditions in the presence of yeast extract and it`s absence, the result showed that the addition of different carbon source especially glucose in presence of yeast initiate the proteolytic activity. 4- Effect of different nitrogen sources on proteolytic activity in optimum conditions showed that the maximum proteolytic activity in presence of peptone and followed by Trypticase instead of Peptone and without peptone no growth for Ps.aeruginosa so no activity for protease. 5- Effect of different concentration of heavy metals (metallic ions) (mg /ml), that showed the effect of five different concentration of each them (10 , 20 , 30 , 40 , 50 mg % ) on the proteolytic activity of Ps. aeruginosa , the control experiment in which the heavy metals was not added (no heavy metals) was the maximum. In case of 10% Mg+2 the largest diameter of clearing zone was (22mm), the gradually remarkable decrease in diameter of clearing zone, were detected with the increasing in concentrations of Mg+2. The opposite manner of proteolytic activity was shown in case of ferrous sulphate Fe +. |