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Showing 6 results for Escherichia Coli
Isolation of enteroinvasive Escherichia coli (EIEC) from diarrhea  in children by polymerase chain reaction (PCR) technique
A Akbari, Mr Pourmand, Mk Sharifi Yazdi, M Hosseini, Mm Soltan Dallal,
Volume 3, Issue 3 (3-2010)
Abstract

Background and Aim: Enteroinvasive Escherichia coli (EIEC) strains include a group of diarrheagenic Escherichia coli (DEC) and are known to cause shigellosis-like symptoms in both adults and children. They belong to a limited number of serotypes and their somatic (O) antigens are identical with, or related to, certain Shigella antigens. EIEC strains are confirmed by demonstration of invasiveness by polymerase chain reaction (PCR) for detection of the ipaH (invasive plasmid antigen H)  gene that is specific for these strains among DEC.Since in our country,Iran study for detection of  these strains. hasnot been carried out therefore the aim of this study was detection of EIEC in diarrheal under 5 year old children in Tehran.

Materials and Methods: During the descriptive study,300stool samples were collected from children with diarrhea in Ali Asghar Hospital and children medicinal center of Tehran during 4 months (April-Jul 2008). E.coli species were isolated by standard bacteriological and biochemical tests. Presence of invasive plasmid antigen H (ipaH) gene in confirmed colonies was investigated by PCR technique.

Results: Among 300 stool specimens studied using culture method and biochemical tests,39(13%) E.coli species were isolated. Among these 39 strains,7(2.3%) strains containing ipaH gene (EIEC) were detected by PCR technique.

Conclusions: Enteroinvasive Escherichia coli (EIEC) in our country, Iran, may be as bacterial pathogen causing childhood diarrhea. Therefore we should apply new techniques for investigation of these strains.


A Survey of Escherichia Coli, Enterococcus and Total Microbial Count of Packaged and Non-Packaged Fresh Vegetables in Tehran
Mohammad Mehdi Soltan Dallal, Maryam Shojaei Zinjanab , Saeid Vahedi, Hamid Mahmoudi , Shahroud Ghanbarzadeh, Fatemeh Hedayati Rad,
Volume 10, Issue 3 (7-2016)
Abstract

Background and Aim: Vegetables are one of the major components of food basket and consumption of them is on the rise. On the other hand, diseases and outbreaks caused by this group of foodstuffs have increasing trend. This study was performed to investigate the microbial contamination of vegetables used in south of Tehran.

Materials and Methods: Hundred fresh packaged and non packaged vegetable samples composed of 10 kinds, were examined based on the methods presented in Iran national standards. For each sample, enumeration of enterococcus and total microbial count was carried out by the pour plate technique in KF agar and plate count agar, respectively. Escherichia coli detection was also performed using lauryl sulfate broth, EC broth, peptone water and MacConkey agar mediums. Biochemical tests namely urea hydrolysis, motility, sulfide hydrogen (SH2) production, gas production and sugar fermentation were conducted as conformational tests of Escherichia coli.

Results: All (100%) of mixed leafy vegetables, spinaches, peppers, kuku (Persian food) vegetables, wheat sprouts and mung been sprouts had contamination higher than acceptable limits. In the case of green onions, basils, kuku vegetables, mushrooms and broccolis, respectively 40, 60, 30, 90 and 30 % of the samples were in contravention with acceptable limits, in terms of at least one parameter.

Conclusion: Our results show that consumption of vegetables specially those used as raw, need more attention at washing point and need to use hygienic rules of health department and health care centers, at shopping and consumption steps.


The Study of Enteropathogenic Escherichia Coli Prevalence by PCR Method in Under-5-Year-Old Children’s Diarrheal Samples Caused by the Country’s Food
Rashin Bahmanabadi , Mohammad Bagher Khalili , Mohammad Mehdi Soltan Dallal,
Volume 11, Issue 6 (3-2018)
Abstract
Background and Aim: Enteropathogenic Escherichia coli (EPEC) pathotypes belong to Enterobacteriaceae family that is known as the cause of gastroenteritis and diarrhea in under-5-year-old children. These bacteria have high prevalence in developed and developing countries that may cause severe illness or even death. The aim of this study was to examine EPEC prevalence in diarrheal samples of children under 5 years -- caused by the country’s food -- by PCR method.
Materials and Methods: In a cross-sectional study, 45diarrheal samples of children suffering from country food outbreaks were transferred to the Department of Microbiology, School of Public Health, Tehran University of Medical Sciences (TUMS). E. coli strain was identified using standard methods and biochemical tests. For the detection of Enteropathogenic E. coli, the presence of eae gene was checked by PCR method, and serologic test using specific antiserum (Mast company, England) was checked by agglutination method on slide.
Results: Of the 45 outbreaks, 28 Escherichia coli were identified, among which 1 isolate (3.6%) was identified as E. coli EPEC. This isolate contained eae gene. Based on the serological response of somatic antigen (O) and flagella (H), the isolated Escherichia coli serotype was EPEC O119B14.
Conclusion: Although the prevalence of EPEC E. coli in children’s diarrheal samples from food outbreaks is low, the presence of these isolates is important and should be considered.

Study of Pomegranate Hydromethanol Extract on Staphylococcus Aureus and Escherichia Coli by Microplate in Laboratory Conditions
Ehsan Estabraghi, Majid Sadeghpour, Amir Mehrabani,
Volume 12, Issue 3 (9-2018)
Abstract
Background and Aim: Pomegranate skin contains large amounts of antibacterial and antioxidant compounds. Increasing antibiotic resistance in Escherichia coli bacteria as a major contributor to urinary tract infections and Staphylococcus 
aureus is a cause of resistance to treatment-resistant infections, a serious need for alternative therapies or compounds that exhibit less resistance. The aim of this study was to investigate the antibacterial properties of Pomegranate extract and inhibit antibiotic resistance of the extract against pathogenic bacteria.
Materials and Methods: After collecting fresh Pomegranate skin, they were dried in a place of sunlight and in shade for 48-72 hours and extraction was done by maceration, in order to determine the minimum level of exposure (Dilution) inhibitor was used from the Muller Hinton Broth and Brain heart Infusion Agar (BHI: Bullet Hit Indicator). The resulting turbidity was measured in a well solution
(microdilution).
Results: The results of microdilution test showed that the growth inhibitory concentration (MIC: Minimum Inhibitory Concentration) was equal to dilution of 1.8 to 25 μL from Pomegranate extract for E. coli and Staphylococcus aureus bacteria. The growth inhibitory concentration (MIC) was equal to a dilution of 1.16 times 12.5 μL of Pomegranate extract.
Conclusion:The extract extracted from Pomegranate skin has the most antimicrobial properties in comparison with other cases. This extract has the most antimicrobial effect on Staphylococcus aureus bacteria from gram-positive bacteria and against E. coli bacteria that is an indicator of fecal contamination. Finally, Staphylococcus aureus showed the highest susceptibility to this extract.

Molecular Analysis of Broad Spectrum Beta-Lactams Resistance Genes TEM, CTX-M and SHV in Escherichia coli Isolates from Traditional Pastry Samples in Yazd
Mohammad Mehdi Soltan Dallal, Mojgan Karimi , Mohammad Kazem Sharifi Yazdi, Hedrosha Molla Aghamirzaei , Mohammad Hossin Mosadegh ,
Volume 13, Issue 2 (7-2019)
Abstract
Background and Aim: The variety of sweets along with significant difference level of hygiene in the production, supplies and high potential contamination of sweets ingredients with Escherichia coli, led to investigate the frequency of broad-spectrum beta lactamase strains of E. coli in sweets and determine the presence of SHV, TEM and CTX-M genes.
Material and methods: In this descriptive cross-sectional study, 150 confectionery samples were collected from traditional confectionery workshops in Yazd. Detection of E. coli strains was carried out by standard biochemical tests and antibiotic susceptibility test was performed using CLSI guidelines. Via combined ESBL disk method on the muller hinton agar medium producing strains were identified. All the ESBL producing strains were evaluated using the PCR test for the existence of SHV, TEM and CTX-M genes.
Results: In 30 isolates, (20%) E.coli was obtained. The results of antibiotic susceptibility test showed that the highest and the lowest antibiotic resistance was related to chloramphenicol l (22 isolates, 73.3%) and Imipenem (8 isolates, 26.6%). The results of the combined disk test was showed that only 9 isolates produced ESBL. The molecular analysis on considered genes indicated that 2, 4 and 3 isolates were positive for presence of TEM, SHV, and CTX-M genes, respectively.
Conclusion: The prevalence of antibiotic-resistant isolates in traditional Yazd sweets in this study highlights the importance of more observing and control measures in the preparation and distribution of sweets.

Identification and Diagnosis of Enterohemorrhagic E. Coli by Molecular Method in Boroujerd City Cows' Milk
Mohammad Mehdi Soltan Dallal, Reza Zandieh Moradi, Ramin Mazaheri Nezhad Fard, Zahra Rajabi,
Volume 13, Issue 5 (1-2020)
Abstract
Background and Aim: Transmission of pathogenic bacteria from animals to humans is possible directly or through the consumption of meat and milk or their products. The aim of this study was to identify and diagnose Enterohemorrhagic Escherichia coli (E. coli) by molecular method in cows' milk in Boroujerd city.
Materials and Methods: In a descriptive cross-sectional study, 150 milk samples were sampled from dairy farms in Boroujerd and its suburbs in four months from the beginning of November 2016 until the end of February 2017. After enrichment, culturing and biochemical tests on EMB agar and IMVIC differential tests, and doing linear culture on Sorbitol McConkey Agar medium to identify negative sorbitol isolates and confirm them by serological testing and eaeA gene identification, milk samples were analyzed by PCR test.
Results: Out of 31 isolates of Escherichia coli species, 6 were isolated as negative sorbitol (19.4%). Of these six isolates, five (16.1%) were identified as negative beta-galactosidase (MUG-) on chrome agar medium. In serological test, all 5 isolates were confirmed by O157: H7 antiserum antibody; besides, in molecular analysis, they had eaeA gene.
Conclusion: The outbreak of 16.1% of enterohemorrhagic E. coli in milk can be of great importance as one of the factors causing diarrhea in the community. Therefore, the outbreaks of consumption of this foodstuff in areas of the country that traditionally still put raw milk in food basket can provide valuable results for the prevention of diarrheal diseases.

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