[Antimicrobial effect of zataria multiflora and rosemarinus officinalis on antibiotic-resistant staphylococcus aureus strains isolated from food]

Staphylococcus aureuse is one of the important pathogens which transmitted by food and has majority of habitant in human and animal community as a pathogen and normal flora. Antibiotic resistant among Staphylococcus aureuse strains is a global health challenge. Regarding to the different therapeutic and antimicrobial effect of Shirazi Zataria multiflora and Rosemarinus officonalis in present work the antibacterial effect of this extract and its synergistic effect with routine antibiotics was investigated. In this in vitro study the antimicrobial effect of Shirazi Zataria multiflora and Rosemarinus officonalis extract on methicillin resistant Staphylococcus aureus [MRSA] and other antibiotic resistant strains to tetracycline, erithromycine, trimethoprim, sulfamethoxazol, together with its MIC and MBC were determined. Also synergistic effect of these extracts with these antibiotics was investigated by paper disc method. Shirazi zataria multiflora, had a significant antibacterial effect against MRSA, and other Staphylococcus aureus resistant strain to tetracycline, erithromycine, trimethoprim, and sulfametoxazol, isolated from food. Production of a suitable herbal medicine with few side effects will give rise to a promising outlook in the treatment of infections caused by antibiotic resistant strains of Staphylococcus aureus

[ trend of drug resistance in toxin and non-toxin producing Shigella Spp. isolated from stool of children with diarrhea]

Diarrhea is recognized as one of the main causes of morbidity and mortality in developing countries. Gastrointestinal diseases can lead to death of many children of less than 5 years of age. The aim of this study was to evaluate the drug resistance pattern in Shigella toxin and non-toxin producing strains in children. In this descriptive analytic study a total of 80 Shigella strains, 60 strains isolated from stool samples of children with diarrhea from Loghman, Emam and Tebi Koodakan Centre Hospitals, and 20 national collection strains isolated and reserved during the last years. The isolates were evaluated for cytotoxin production by using cell culture technique [Hela cell]. Our study included 54 strains of S. flexneri, 14 strains of S.sonnei, 10 strains of S. boydii and 2 strains of S. dysenteriae. Data were analyazed by means of chi-square and Fisher's exact test. Of 80 strains 9 [11.25%] showed cytotoxic effect. Chi-square test showed no significant difference between the isolated and national collection strains [P >/= 0.05].There was no correlation between the cytotoxic activity and clinical symptoms such as abdominal pain, nausea, and frequency of passing stools / day, but other symptoms like fever and presence of blood in the stool had correlation with cytotoxin production. The results of this study showed that there was no significant difference in the antimicrobial resistance pattern between toxin and non-toxin producing Shigella strains isolated from the clinical samples and the standard national collection

[Antibacterial effects of Rosmarinus officinalis on methicillin - resistant Staphylococcus aureus isolated from patients and foods]

Methicillin-resistant Staphylcoccus aureus [MRSA] is considered a major problem in the world. This strain colonizes nose and causes increased incidence of nosocomial infections, mortality and morbidity. Rosemary [Rosmarinus officinalis] is a herbal medicine widely used all over the world. The aim of this study was to evaluate the in vitro antimicrobial activity of rosemary essence on MRSA isolated from patients and food. 200 strains of MRSA, 100 from patients and 100 from food samples, were collected and analyzed in Tehran, during the last year. 28 MRSA strains and multi drug resistant [MDR] strains were isolated. The antimicrobial activity of the rosemary essence against different isolates of the microorganism was evaluated by disk diffusion and macro broth dilution methods. MRSA isolates belonged to 25% and 60% of food and clinical samples, respectively. The results showed effective and similar antimicrobial activity of Rosmarinus officinalis on broth clinical and food samples with an inhibition zone of 20mm in diameter. The minimum inhibitory concentration [MIC] and minimum bactericidal concentration [MBC] in our study were 1.40 mg/ml and 2.81 mg/ml, respectively. Overuse of antibiotics has led to extensive bacterial resistance to antibiotics, which demonstrates the need for use of new antimicrobial agents. Considering increasing prevalence of MRSA strains and the beneficial effect of rosemary essence on these strains, this essence can be recommended for the treatment of MRSA infections

Prevalence of clostridium difficile- associated diarrhean in hospitalized patients with nosocomial diarrhea

Clostridium difficile is a frequently identified cause of nosocomial gastrointestinal disease. It has been proved to be a causative agent in antibiotic-associated diarrhea, antibiotic-associated colitis, and pseudomembraneous colitis. This study was aimed to determine the prevalence of C.difficile- associated diarrhea in hospitalized patients with nosocomial diarrhea. The 942 hospitalized patients stool samples with nosocomial diarrhea were collected at three hospitals in Tehran from Dec 2002 to Feb 2004.All the stool samples were cultured and in 97 [prevalence: 10.9%] samples grew C.difficile that 57 [prevalence: 6.1%] isolates were toxigenic by cytotoxicity assay and so 57 patients had C.difficile- associated diarrhea. Results of statistical analysis showed significant difference between the rate of C.difficile associated diarrhea and the patients ages [P<0.05]