Showing 4 results for E. Coli
A Nazemi, M Naderi, M Jafarpour, M Mirinargesi, Sh Sharifi,
Volume 4, Issue 2 (10-2010)
Abstract
Abstract Bachground and objectives: The ability of adherence to the surface of host cell is very critical in the colonization of microbial pathogens. It has been revealed that E. coli strains that infect urinary tracts have different fimbrea such as I, S, FIC, Dr, and fimbrial adhesions. Material and Methods: In this study, 363 urine samples were obtained from patients with urinary tract infections reffered to clinical laboratories in Western areas of Tehran ,2008-2010 by using biochemical tests,200 samples were confirmed to be E.coli.First, DNA was extracted by boiling method and then the presence of fimbria fim, sfa, pap, foc, and afa genes tested by PCR. Results: In 200 samples, the frequency of fimbria fim, sfa, pap, foc, and afa genes are188 (%94 ), 34 (%17), 20 (%10), 61 (%31) and 71 (%35.5), respectively. Conclusion: The resultes show that FIM ans SFA are the most fimbrial genes of E. coli isolated from urine samples .This information can be valuable in etiology of urinary tract infection (UTI), UTI administration, and making of new vaccines. Key words: Urinary tract infection, fimbria, Uropathogenic E. coli (UPEC)
Noroozi , R, Mehdinezhad, Mh, Zafarzadeh A,
Volume 5, Issue 2 (10-2011)
Abstract
Abstract: Background and objectives: There is a great interest in photocatalytic oxidation of contaminants, using ZnO, in recent years. The main objective of this research was to study photocatalytic disinfection of E. coli bacteria as water microbial pollution index, using nano particles of ZnO and a UV lamp in a batch reactor. Material and Methods: In this study, the contaminated water sample was prepared through adding 102 and 103 E. coli bacteria per ml of raw water. The contaminated water entered the photocatalytic oxidation reactor and removal efficiency of E. coli bacteria in different conditions were studied, including pH (5.5, 7, and 9), time (10, 20, 30, 40, 50 and 60 mins), dose of nano particles ZnO (0.2,0.4,0.8 and 1 gr/l), number of bacterium (102 and 103 per milliliter) and voltage of UV-C lamp, 27 volts. Characterizations of ZnO nanoparticles were determined using scanning electron microscope equipped with Energy Dispersive X-ray Analysis (EDX) system and X-ray diffraction (XRD) method. Results: Photocatalytic process efficiency is enhanced by increasing reaction time and dose of nano particles ZnO in the presence of UV lamp irradiation. The results show that the best conditions for removal of 102 and 103 bacteria per milliliter are obtained from condition including pH of 7, reaction time of 30 mins, 0.8 gr/l doses of nano particles ZnO and 27-volt-UV lamp. Conclusion: The results indicate that the increase of reaction time and dose of nano particles ZnO, in the presence of radiation UV lamp, have the most significant effect on photocatalytic efficiency. Based on the results, photocatalytic can be promising method for removal of E. coli bacterium from drinking water. Keywords: Photocatalytic, E. coli, irradiation UV, ZnO nanoparticles, water treatment
Safaari, M, Zolfaghari, Mr, Shakib, P, Rouhi, S,
Volume 8, Issue 5 (1-2015)
Abstract
Abstract Background and Objective: Diarrheal diseases may occur in all age groups, worldwide. Escherichia coli (E. coli O157: H7) is one of the most important bacterial agents causing this disease. The purpose of this study was to assess the prevalence of diarrhea in patients with acute diarrhea caused by this bacterium. Material and Methods: In this study, 214 stool samples were collected from acute diarrheic patients in hospitals and clinical laboratories of Malayer city, Iran. The samples were cultured in rich, differentiation, specific and selective medium. To detect E. coli O157: H7, rapid detection method and antisera were used . Results: In 12.15% of the samples, lactose fermentation was observed and E. coli was afirmed. The results of lactose positive samples showed that 6.54% were negative-β- Glucuronidases and were confirmed as E. coli O157. Finally, by using O157: H7 antisera, 1.87% of 14 samples that were negative- β-Glucuronidases were asserted as E. coli O157. Conclusion: based on the results, the prevalence of E. coli O157: H7 is higher in children and elders than the others. Food and water play a significant role in transferring E. coli. Keywords: Prevalence, E. coli O157: H7, Gastroenteritis, Patients
Seyedeh Masoumeh Mirtaghi, Parisa Torbati Nejad , Masoumeh Mazandarani, Fasiheh Livani, Hanieh Bagheri ,
Volume 10, Issue 5 (9-2016)
Abstract
Background and Objective: Nowadays, incidence of antibiotic-resistance among pathogenic bacteria has increased due to indiscriminate use of antimicrobial drugs for treatment of diseases, especially urinary tract infections. Medicinal plants are also of great importance as antibacterial agents. Therefore, the aim of this study was to determine the antibacterial effect of ethanolic extract of nettle (Urtica dioica L.) leaves using two methods of disk diffusion and well diffusion.
Methods: Ethanolic extract of nettle leaves was prepared by the percolation method. Effect of different concentrations of the extract on Escherichia coli (PTCC1399), Staphylococcus aureus (PTCC 1431), Staphylococcus epidermidis (PTCC 1435) and Staphylococcus saprophyticus (PTCC1440) was evaluated using the disk diffusion and well diffusion methods by measuring diameter of growth inhibition zone. Gentamicin and propylene glycol were used as positive and negative control, respectively.
Results: In both methods, especially in the well diffusion, the ethanolic extract of nettle leaves had favorable inhibitory effect on the growth of S. aureus, S. epidermidis and S. saprophyticus. In the well diffusion method, the highest rate of susceptibility to the extract (89%) was related to S. saprophyticus and S. epidermidis.
Conclusion: The ethanolic extract of nettle leaf has good inhibitory effect on the growth of S. aureus (especially in the well diffusion method), which confirms the traditional use of this plant for the treatment of urinary tract infections.
Keywords: Antibacterial Effect, Staphylococcus, E. Coli, Ethanolic Extract, Nettle (Urtica dioica L.).
