Behnam Afsar; Ebrahim Fataei; Ali Akbar Imani
Abstract
Background: Failure to observe proper hygiene principles of water and swimming pool environment is effective in causing health problems and transmission of infectious diseases to swimmers. This study aimed to analyze the level of Escherichia coli and Heterotrophic Plate Count in mineral pools in Sarein.Methods: ...
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Background: Failure to observe proper hygiene principles of water and swimming pool environment is effective in causing health problems and transmission of infectious diseases to swimmers. This study aimed to analyze the level of Escherichia coli and Heterotrophic Plate Count in mineral pools in Sarein.Methods: For this purpose, sampling was performed in each season, and the samples were tested according to the standard method. Shapiro-Wilk and Kolmogorov-Smirnov test was used to determine the normality or abnormality of the data. Then, through ANOVA, the differences between the seasons and the pools were compared in terms of the studied parameters.Results: The results of the analysis of variance showed that there was no significant difference between the spas in terms of the measured parameters. A comparison of the average data showed that the amount of contamination of mineral spas during the seasons with E. coli was more than the allowable value announced by the National Standard Organization of Iran. The amount of residual chlorine in all samples was zero and the pH was equal to 6.8. The results of principal component analysis showed that mineral spas No. 6, 2, and 11 had the highest HPC (Heterotrophic Plate count) and pH and 9 Cheshmeh, Ershad, and Ghahveh Sui mineral spas based on the second component had the highest E. coli; No. 7 had the lowest E. coli.Conclusion: Finally, it can be concluded that the cause of the contamination of mineral swimming pools in Sarein city is the high volume of passengers and the lack of proper sanitary management of swimming pools.
Seyed Mohammad Amin Mahdian; Abbasali Raz; Navid Dinparast Djadid; Hamzeh Alipour
Abstract
Background: A given amino acid sequence can be encoded by a huge number of different nucleic acid sequences. These sequences, however, have proved not to be equally useful. The choice of sequence can significantly impact the expression of an encoded protein. Given the importance of protein-coding sequence ...
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Background: A given amino acid sequence can be encoded by a huge number of different nucleic acid sequences. These sequences, however, have proved not to be equally useful. The choice of sequence can significantly impact the expression of an encoded protein. Given the importance of protein-coding sequence and promising industrial and medicinal applications of Clostridium histolyticum collagenase, this study examined the codon optimization of the Col H gene so as to enhance collagenase expression in Escherichia coli (E. coli).
Methods: This is an experimental study in which the CDS of Col H gene was optimized according to the codon usage of E. coli, using Gene Designer software (DNA 2.0).
Results: The results revealed that relative frequency of codon usage in Col H gene was adapted to the most preferred triplets in E. coli in such a way that codon usage bias in E. coli was enhanced after codon optimization. The higher level of collagenase expression was more likely the result of substituting rare codons with optimal codons.
Conclusion: The findings of this study suggest that codon optimization provides a theoretical improvement in Col H gene expression in E. coli. Nevertheless, experimental research is needed to confirm the improvement.
Masoomeh Ghanavat Amani; Reza Jalilzadeh Yengejeh
Abstract
Background: The main aspect of water purification to serve the human drinking purpose is the elimination of microbial agents and pathogens using the disinfectants. Although chemicals such as chlorine are the most common water disinfectants, the researchers have always sought to identify and ...
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Background: The main aspect of water purification to serve the human drinking purpose is the elimination of microbial agents and pathogens using the disinfectants. Although chemicals such as chlorine are the most common water disinfectants, the researchers have always sought to identify and introduce new disinfectants due to the formation of potentially carcinogenic byproducts. Owing to the high efficiency and lack of hazardous residues, nanoparticles have recently been used in many scientific activities. Objectives: In this study conducted in summer 2018, the copper and silver nanoparticles were used to remove Escherichia coli (E. coli) and Klebsiella from the synthetic and real samples. Methods: This experimental study was performed on Nano particles and by adding nanoparticles to samples (real and synthetic), the efficiency of removal of E. coli and Klebsiella was measured by MPN and pure plate methods. Results: By optimizing the conditions, in 200 ppm concentration as 2ml with pH=7, it has the highest removal rate of 99.25% for E. coli, and in 250ppm concentration as 1.5 ml with pH = 7, it has the removal rate of 81.25% for Klebsiella. Conclusions: In this case study, we found that using Nano particles led to high level of efficiency at a short time; moreover, they were cost-effective and environmentally friendly.
Mahtab Hadadi; Yalda Malekzadegan; Hamid Heidari; Hadi Sedigh Ebrahim-Saraie; Mohammad Motamedifar
Volume 4, Issue 4 , October 2016, , Pages 194-198
Abstract
AbstractBackground: Escherichia coli, known as a clinically significantbacteria, can cause a wide range of infections, including urinarytract infections (UTIs), blood stream infections (BSIs), andcan frequently be isolated from various clinical specimens.Evaluation of antimicrobial resistant pattern ...
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AbstractBackground: Escherichia coli, known as a clinically significantbacteria, can cause a wide range of infections, including urinarytract infections (UTIs), blood stream infections (BSIs), andcan frequently be isolated from various clinical specimens.Evaluation of antimicrobial resistant pattern is a necessaryaction, especially about such bacteria which are frequent andlife threatening. The aim of this study was to determine thefrequency and antimicrobial resistance pattern of E. coli isolatesobtained from various clinical specimens.Methods: This retrospective study was performed within a sevenmonth period from January 2015 to August 2015 at a specializedwomen and children hospital in Shiraz, Iran. E. coli isolates wereobtained from various clinical specimens and identified usingstandard microbiological procedure. Antimicrobial susceptibilitypatterns were determined using disk diffusion method inaccordance with CLSI recommendation.Results: Of the total 130 positive cultures, the majority of E.coli isolates were obtained from urine (96=73.8%) and blood(11=8.5%) specimens. Overall, gentamicin (70.8%) was theeffective antibiotic for the tested E. coli isolates. E. coli isolatesobtained from urine specimens showed the highest resistancerates against ampicillin (84.4%) and nalidixic acid (61.5%);while they showed the most sensitivity to gentamicin (79.2%),nitrofurantoin (70.8%) and ciprofloxacin (66.7%). Moreover,the highest antibiotic resistance rates belonged to the isolatesrecovered from endotracheal tube (ETT).Conclusion: The results showed that gentamicin was the mosteffective antibiotic against E. coli infections. However, inaddition to the gentamicin, we can recommend nitrofurantoinand ciprofloxacin as the other effective agents for UTIs.
Mahsa Moazen; Samane Rahmdel; Seyedeh Maryam Abdollahzadeh; Maryam Ranjbar Zahedani; Seyed Mohammad Mazloomi
Volume 2, Issue 2 , April 2014, , Pages 49-53
Abstract
Background: Although enteral feeding solutions are used to reduce the morbidity and mortality in many malnourished and hospitalized patients, microbial contamination of these products may lead to severe infections, especially in immune suppressed ones. The aim of this study was to evaluate the microbiological ...
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Background: Although enteral feeding solutions are used to reduce the morbidity and mortality in many malnourished and hospitalized patients, microbial contamination of these products may lead to severe infections, especially in immune suppressed ones. The aim of this study was to evaluate the microbiological quality of commercial enteral feedings in two hospital settings in Shiraz. Methods: Twenty commercial enteral feedings were collected immediately after preparation and then homogenized and serially diluted on the same day. MPN methods were used to evaluate the total viable count and Escherichia coli count. They were also tested for total coliform (pour plate method) and the presence of coagulase positive staphylococci. The results were compared with standard limits. Results: All samples had a total viable count lower than 104 colony forming units (CFU) per g (the maximum recommended level of FDA standard).For all enteral feedings, coliform counts were not detectable (<10 CFU/g).Escherichia coli counts were also lower than those of Brazilian legislation (<3 CFU/g). Coagulase positive staphylococci were recovered just from one sample (5%). Conclusion: Freshly prepared commercial enteral feeding samples h ad a cceptable m icrobial q uality. S uch p roducts are considered to be more acceptable than hospital prepared ones. However, further steps involved in the preparation and administration of commercial feedings can be sources of microbial contamination. Thus implementation of hygienic practices and monitoring procedures during preparation and administration can be suggested.
