Microbiology
Shabnam khavandi; Mohsen Arzanlou; Roghayeh Teimourpour; Hadi Peeridogaheh
Abstract
Background & Objective: Carbapenem-resistant is Gram-negative bacteria representing a worldwide public health problem. The present study aims to survey the phenotypic and genotypic characteristics of carbapenem-resistant Escherichia coli isolates collected from hospitalized patients and outpatients ...
Read More
Background & Objective: Carbapenem-resistant is Gram-negative bacteria representing a worldwide public health problem. The present study aims to survey the phenotypic and genotypic characteristics of carbapenem-resistant Escherichia coli isolates collected from hospitalized patients and outpatients in Ardabil province, Iran.Methods: Two hundred samples were collected from the patients who had already been referred to the hospitals in Ardabil, Iran, from January to June 2017. Each patient's social and demographic data were recorded in the first step. The resistance profile of all E. coli isolates against imipenem and meropenem antibiotics were determined using the Kirby-Bauer disk diffusion method. Moreover, the broth microdilution method determined the Minimum Inhibitory Concentration (MIC) of E. coli isolates to imipenem. The Carbapenem Inactivation Method (CIM) and Carba NP test were employed for screening carbapenem-resistant strains. The frequency of carbapenem-encoding genes was determined using Polymerase Chain Reaction (PCR) method. The Enterobacterial Repetitive Intergenic Consensus (ERIC)-PCR analysis was used to evaluate the genetic relatedness of E. coli isolates.Results: Out of 200 urine samples, 66% (n = 132) of the samples were collected from women. The patients' age varied from 1 month to 93 years. Results of the disk diffusion method revealed that 33% (n=66/200) of E. coli isolates were resistant to imipenem. However, imipenem resistance was detected in 37% (n = 74/200) of the E. coli isolates using broth microdilution method. All E. coli isolates were negative in CIM and Carba NP tests. Moreover, we could not detect any carbapenemase encoding genes among E. coli isolates. The ERIC-PCR method revealed the E. coli strains were classified into 39 clusters with 80% similarity.Conclusion: It appears that E. coli is the most common cause of urinary tract infection in Ardabil province.
Microbiology
Reza Ranjbar; Afsar Tabatabaee; Payam Behzadi; Rohollah Kheiri
Abstract
Background: Escherichia coli is a commensal-pathogenic organism, which includes a wide range of strains. Despite several advanced molecular-genomic technologies for detecting and identifying different strains of E. coli, Enterobacterial Repetitive Intergenic Consensus Polymerase Chain Reaction ...
Read More
Background: Escherichia coli is a commensal-pathogenic organism, which includes a wide range of strains. Despite several advanced molecular-genomic technologies for detecting and identifying different strains of E. coli, Enterobacterial Repetitive Intergenic Consensus Polymerase Chain Reaction (ERIC-PCR) technique is a quick, sharp and cost effective fingerprint method. The major purpose of the present study was to determine the distribution of ERICs within E. coli strains isolated from different healthy animal stool specimens including hens, sheep, and cows, as an appropriate and quick molecular-genomic tool. Methods: The animal stool samples were obtained during 1 year (October 2012 to October 2013), from animal husbandries around Tehran and Alborz provinces, Iran. After screening processes, the E. coli bacteria were isolated and cultured via standard microbiological methods. The DNA molecules of E. coli bacteria were harvested and Enterobacterial Repetitive Intergenic Consensus Polymerase Chain Reaction (ERIC-PCR) was applied for bacterial molecular genotyping. The ERIC-PCR products were run on 1% gel electrophoresis. The final images regarding gel electrophoresis banding patterns were used for dendrogram generation via the GelClust software. Results: Of 120 isolated samples, 115 different strains were recognized as E. coli. The fingerprint patterns involved 380 to 3280 bp bands. The predominant bands included 2900 bp, 1200 bp, and 1200 bp in stool samples of hens, sheep, and cows, respectively. The highest frequencies and diversities were seen among E. coli strains isolated from hens and sheep stool samples. Conclusion: The DNA profiles were clearly detectable via specific fingerprint patterns. The ERIC-PCR seemed to be a good approach for molecular typing of E. coli strains isolated from different animal sources.
Saeed Rezaei-Zarchi; Aisha Javed; Madiha Javeed Ghani; Safieh Soufian; Fatemeh Barzegari Firouzabadi; Abdolmajid Bayanduri Moghaddam; Seyed Hossein Mirjalili
Volume 5, Issue 2 , March 2010, , Pages 83-89
Abstract
Background: and Objectives:The aim of this study was to detect the antibacterial properties of 0.01, 0.5 and 1% nano-TiO2 and -CdO against E. coli. Materials and Methods: E. coli was cultured in liquid and agar nutrient medium to evaluate the antibacterial effects of 0.01, 0.05 and 1% of both ...
Read More
Background: and Objectives:The aim of this study was to detect the antibacterial properties of 0.01, 0.5 and 1% nano-TiO2 and -CdO against E. coli. Materials and Methods: E. coli was cultured in liquid and agar nutrient medium to evaluate the antibacterial effects of 0.01, 0.05 and 1% of both nano-TiO2 and -CdO via the optical density (OD) and log CFU/ml measurements. Results: Non-significant effect was seen for 0.01% of both nano-specimens. While, 0.05 and 1% of both nanoparticles showed considerably decreased bacterial number. A 4.5 and 1.9 times decrease in the OD value was found in the presence of 1 and 0.5% nano-TiO2, respectively(P< 0.001). 1.5 and 3.3 times decreased OD was seen in the presence of 0.5 and 1% nano-CdO, respectively, as compared to control (P<0.001). In the second study, 6.3 log CFU/ml of E. coli were present in the cultures treated with 1% nano-TiO2 and CdO at 4 ºC in water. Control E. coli cells survived for 12 days while complete cell death was seen when 1% nano-TiO2 was applied for 13 hours as compared to 1% nano-CdO, which showed complete cell death after 15 hours. In the third study, E. coli was grown in the agar medium with and without both nanoparticles and suppressed growth (4.5 and 5.6 times; P<0.001) was seen in the presence of 1% nano-CdO and -TiO2, respectively. Conclusion: In spite of the fact that both nanoparticles showed bactericidal activity, nano-TiO2 has proven to be more efficient antibacterial agent as compared to nano-CdO.
Ali Jazayeri Moghadas; Gholamreza Irajian
Volume 4, Issue 3 , June 2009, , Pages 105-108
Abstract
Background and Objectives: Urinary tract infection is one of the most common bacterial infections in the human population, and more frequent infection during pregnancy. With notice to this point that most of urinary tract infections during pregnancy are asymptomatic, they could lead to serious ...
Read More
Background and Objectives: Urinary tract infection is one of the most common bacterial infections in the human population, and more frequent infection during pregnancy. With notice to this point that most of urinary tract infections during pregnancy are asymptomatic, they could lead to serious complications such as prematurity, low-birth weight, hypertension, and higher fetal mortality rates ifuntreated. This study was aimed to determine the prevalence of asymptomatic bacteriuria, bacterial agents and their antibiotic susceptibility pattern in pregnant womenattendingSemnan public health centers during 2007-8. Patients and Methods: In this descriptive cross sectional study,pregnant women attending Semnan public health centers during May 2007 and June 2008 were investigated. Clean catch mid stream urine samples were collected and cultured on Eosin Metylene Blue agar and Blood agar by calibrated loop method. Suspected colonies were identified, antibiotic susceptibility test was done. Results: Of 297 samples, 10 (3.3%) were positive for asymptomatic urinary tract infection. The dominant bacterial isolate was Escherichia coli (70%). The antibiotic susceptibility was observed to ciprofloxacin, ceftazidime and cefotaxime (80%), the most resistance was amoxicillin- clavulanic acid (90%). Conclusion: Frequency of asymptomatic UTI in pregnant women in this study is significantly lower than similar studies. Antibiotic susceptibility rate to using antibiotics do not show significant differences with most other studies.