Publications by authors named "Parviz Owlia"

78 Publications

Evaluation of Antibiotic Resistance Pattern, Alginate and Biofilm Production in Clinical Isolates of .

Iran J Public Health 2021 Feb;50(2):341-349

Molecular Microbiology Research Center (MMRC), Faculty of Medicine, Shahed University, Tehran, Iran.

Background: is one of the most common opportunistic bacteria causing nosocomial infections, which has significant resistance to antimicrobial agents. This bacterium is a biofilm and alginate producer. Biofilm increases the bacterial resistance to antibiotics and the immune system. Therefore, the present study was conducted to investigate the biofilm formation, alginate production and antimicrobial resistance patterns in the clinical isolates of .

Methods: One hundred isolates of were collected during the study period (from Dec 2017 to Jul 2018) from different clinical samples of the patients admitted to Milad and Pars Hospitals at Tehran, Iran. Isolates were identified and confirmed by phenotypic and genotypic methods. Antimicrobial susceptibility was specified by the disk diffusion method. Biofilm formation and alginate production were measured by microtiter plate and carbazole assay, respectively.

Results: Sixteen isolates were resistant to all the 12 studied antibiotics. Moreover, 31 isolates were Multidrug-Resistant (MDR). The highest resistance rate was related to ofloxacin (36 isolates) and the least resistance was related to piperacillin-tazobactam (21 isolates). All the isolates could produce the biofilm and alginate. The number of isolates producing strong, medium and weak biofilms was equal to 34, 52, and 14, respectively. Alginate production was more than 400 μg/ml in 39 isolates, 250-400 μg/ml in 51 isolates and less than 250 μg/ml in 10 isolates.

Conclusion: High prevalence of MDR, biofilm formation, and alginate production were observed among the clinical isolates of . The results also showed a significant relationship between the amount of alginate production and the level of biofilm formation.
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http://dx.doi.org/10.18502/ijph.v50i2.5349DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7956088PMC
February 2021

Frequency of five Escherichia Coli pathotypes in Iranian adults and children with acute diarrhea.

PLoS One 2021 4;16(2):e0245470. Epub 2021 Feb 4.

Department of Molecular Biology, Pasteur Institute of Iran, Tehran, Iran.

Background: Knowledge about the distribution of Escherichia Coli (E. coli) pathotypes in Iran is limited. This nation-wide survey aims to provide a comprehensive description of the distribution of five pathogenic E. coli in Iran.

Methods: Stool samples were collected from 1,306 acute diarrhea cases from 15 provinces (2013-2014). E. coli-positive cultures underwent PCR testing for the detection of STEC, ETEC, EPEC, EAEC, and EIEC pathotypes. Pathotype frequency by province, age-group, and season was estimated.

Results: 979 diarrhea samples (75.0%) were culture-positive for E. coli (95% CI: 72.6, 77.3%), and 659 (50.5%) were pathogenic E. coli (95% CI: 47.8, 53.2%). STEC was the most frequent pathotype (35.4%). ETEC (14.0%) and EPEC (13.1%) were the second and the third most frequent pathotypes, respectively. EAEC (4.3%) and EIEC (0.3%) were not highly prevalent. Fars (88.7%) and Khorasan-e-Razavi (34.8%) provinces had the highest and lowest frequencies, respectively. E. coli pathotypes were more frequent in warmer than cooler seasons, showed the highest frequency among children under five years of age (73%), and had no significant association with participants' gender.

Conclusions: Diarrheagenic E. coli may be an important cause of acute diarrhea in adults and children in Iran. STEC and ETEC seem to be widespread in the country with a peak in warmer seasons, impacting the recommended use of seasonal STEC and ETEC vaccines, especially in high-risk groups. Monitoring the incidence of E. coli pathotypes, serotypes, and antibiotic resistance over time is highly recommended for evaluation of interventions.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0245470PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7861387PMC
February 2021

Protective response against with ferric iron receptors HemTR-BauA in a murine sepsis model.

Future Microbiol 2021 Feb 2;16:143-157. Epub 2021 Feb 2.

Department of Microbiology, Molecular Microbiology Research Center, School of Medicine, Shahed University, Tehran, 3319118651, Iran.

Iron uptake and metabolism pathways are promising targets in vaccine development as an alternative strategy for antibiotics. HemTR, a putative heme receptor of , was expressed and its protectivity against was determined singly or in combination with the siderophore receptor, BauA, in mice. High level of IgG was elicited. There was a delay in mice mortality with reduced bacterial loads in internal organs in the sublethal challenge. Protection was better in the HemTR-BauA group in both lethal and sublethal challenges. Passive transfer of anti-HemTR and anti-BauA partially protected mice against infection. HemTR in combination with other iron receptors could contribute to the development of protective vaccines against .
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http://dx.doi.org/10.2217/fmb-2020-0133DOI Listing
February 2021

Specific egg yolk immunoglobulin as a promising non-antibiotic biotherapeutic product against Acinetobacter baumannii pneumonia infection.

Sci Rep 2021 Jan 21;11(1):1914. Epub 2021 Jan 21.

Department of Biology, Shahed University, Tehran-Qom Express Way, 3319118651, Tehran, Iran.

Acinetobacter baumannii is a serious health threat with a high mortality rate. We have already reported prophylactic effects of IgYs raised against OmpA and Omp34 as well as against inactivated whole-cell (IWC) of A. baumannii in a murine pneumonia model. However, the infection was exacerbated in the mice group that received IgYs raised against the combination of OmpA and Omp34. The current study was conducted to propose reasons for the observed antibody-dependent enhancement (ADE) in addition to the therapeutic effect of specific IgYs in the murine pneumonia model. This phenomenon was hypothetically attributed to topologically inaccessible similar epitopes of OmpA and Omp34 sharing similarity with peptides of mice proteins. In silico analyses revealed that some inaccessible peptides of OmpA shared similarity with peptides of Omp34 and Mus musculus. Specific anti-OmpA and anti-Omp34 IgYs cross-reacted with Omp34 and OmpA respectively. Specific IgYs showed different protectivity against A. baumannii AbI101 in the murine pneumonia model. IgYs triggered against OmpA or IWC of A. baumannii were the most protective antibodies. IgY triggered against Omp34 is ranked next after those against OmpA. The lowest protection was observed in mice received IgYs raised against the combination of rOmpA and rOmp34. In conclusion, specific IgYs against OmpA, Omp34, and IWC of A. baumannii could serve as novel biotherapeutics against A. baumannii pneumonia.
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http://dx.doi.org/10.1038/s41598-021-81356-8DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7820402PMC
January 2021

COVID-19 and Skin Manifestations: An Overview of Case Reports/Case Series and Meta-Analysis of Prevalence Studies.

Front Med (Lausanne) 2020 29;7:573188. Epub 2020 Oct 29.

Department of Microbiology, School of Medicine, Alborz University of Medical Sciences, Karaj, Iran.

Since the onset of the 2019-nCoV disease (COVID-19), many skin manifestations have been reported in COVID-19 patients. This study aims to provide a systematic review and meta-analysis of various skin manifestations among patients with COVID-19 through case reports/case series and prevalence studies. A systematic literature search strategy was conducted by reviewing original research articles published in Medline, Web of Science, and Embase databases in 2020. Statistical analysis was performed using STATA software, version 14.0 (Stata Corporation, College Station, Texas, USA) to report the global prevalence of skin manifestations among patients with COVID-19. Forty-three studies (35 articles were case reports/case series, and 8 articles were prevalence studies) were included in our study. A meta-analysis of prevalence studies showed that skin manifestations among patients with COVID-19 were reported in four countries (China, Thailand, France, and Italy), with an overall prevalence of 1.0% [(95% CI) 0.1-1.9] among 2,621 patients. Evaluation of the results of the case reports/case series revealed that, out of 54 patients with COVID-19, 48 patients (88.8%) showed skin manifestations. Erythematous rash (59.1%) and urticaria (14.8%) were the most common skin manifestation reported in studied patients. Infection with 2019-nCoV may lead to skin manifestations with various clinical symptoms. These clinical features combined with clinical symptoms of COVID-19 may aid in the timely diagnosis of patients with COVID-19.
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http://dx.doi.org/10.3389/fmed.2020.573188DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7668416PMC
October 2020

The global prevalence of Chlamydia pneumoniae, Helicobacter pylori, Cytomegalovirus and Herpes simplex virus in patients with coronary artery disease: A systematic review and meta-analysis.

Microb Pathog 2021 Mar 6;152:104572. Epub 2020 Nov 6.

Department of Microbiology, School of Medicine, Alborz University of Medical Sciences, Karaj, Iran. Electronic address:

Background And Aim: Coronary Artery Disease (CAD) is one of the most important causes of death worldwide. The aim of this study was to determine the prevalence of C. pneumoniae, H. pylori, Cytomegalovirus (CMV) and Herpes simplex virus (HSV) in CAD patients based on published serological and molecular studies.

Methods: A systematic literature search was conducted in Medline (via PubMed), Embase, Scopus and Web of Science databases (1996-2019). Both molecular and serological studies were analyzed using STATA software (Version 14).

Results: 145 studies were included for final analysis. We gathered and investigated the prevalence of C. pneumoniae (25.1% [95% confidence interval (CI) 21.5-28.8%]), H. pylori (12.8% [(95% CI) 4.0-22.0%]), CMV (64.4% [(95% CI) 57.7-73.0%]) and HSV (31.8% [(95% CI) 21.5-42.2%]) in CAD patients from the analysis of molecular studies. Additionally, in serological studies, the prevalence of mentioned pathogens were 72.7% [(95% CI) 67.8-77.6%], 63.3% [(95% CI) 60.0-66.5%], 62.2% [(95% CI) 58.0-66.3%] and 34.3% [(95% CI) 23.6-45.1%] respectively.

Conclusion: Interestingly, there was only a significant increase in the prevalence of C. pneumoniae and H. pylori in serological studies compared to the reported data from molecular studies, while the prevalence of CMV and HSV were the same in both types of studies.
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http://dx.doi.org/10.1016/j.micpath.2020.104572DOI Listing
March 2021

Author Correction: Comprehensive genomic analysis of a plant growth-promoting rhizobacterium Pantoea agglomerans strain P5.

Sci Rep 2020 Jul 21;10(1):12068. Epub 2020 Jul 21.

Energy and Environmental Biotechnology Department, National Institute of Genetic Engineering and Biotechnology, Tehran, Iran.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.
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http://dx.doi.org/10.1038/s41598-020-69169-7DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7374572PMC
July 2020

Proliferative Effect of FadA Recombinant Protein from Fusobacterium nucleatum on SW480 Colorectal Cancer Cell Line.

Infect Disord Drug Targets 2020 Jul 19. Epub 2020 Jul 19.

Department of Microbiology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran. Iran.

Background And Aim: Colorectal Cancer (CRC) is one of the most frequent cancers diagnosed in both men and women worldwide. Fusobacterium nucleatum adhesin A (FadA) has an important potential factor in the development or progression of CRC. The aim of the present study was to evaluate the proliferative effect of recombinant FadA on SW480 colorectal cancer cell line.

Materials And Methods: The recombinant pET21(b)-fadA plasmid was synthesized and transformed into competent E.coli DH5α. In the next step, induction and expression of recombinant FadA were carried out in E. coli BL21 (DE3) competent cells. Expression and purification of protein were successfully done and it was analyzed and confirmed by SDS-PAGE and western blotting. The proliferative effect of purified FadA on SW480 CRC cell line was evaluated using MTT assay and cell counting methods.

Results: Visualization of the specific band isolated from the linear plasmid on the agarose gel confirmed the presence of the desired gene. After electrophoresis and Coomassie blue staining, the protein of interest with an approximate molecular weight of 13KDa was detected. The MTT assay, similar to cell counting methods, revealed that FadA dose and timedependently promoted SW480 cell growth and proliferation in 24, 48 and 72 hours.

Conclusion: The results showed that FadA stimulates proliferation of SW480 colorectal cancer cell line with a dose and time-dependent manner.
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http://dx.doi.org/10.2174/1871526520666200720113004DOI Listing
July 2020

Protective Efficacy of the OprF/OprI/PcrV Recombinant Chimeric Protein Against in the Burned BALB/c Mouse Model.

Infect Drug Resist 2020 9;13:1651-1661. Epub 2020 Jun 9.

Department of Microbiology, Karaj Branch, Islamic Azad University, Karaj, Iran.

Background: infection is the major cause of death in burn patients. Thus, in this study, a chimeric vaccine harboring the OprF-OprI-PcrV was designed and expressed in . The immunogenicity of the recombinant chimer, OprI, OprF, and PcrV was studied in a burned mouse model.

Methodology: Recombinant proteins including the proposed chimer, OprF, OprI, and PcrV were expressed in the . Mice were immunized with the purified recombinant proteins, and the antibody titre was estimated in the sera obtained from immunized mice. Immunized and control mice were challenged with 2, 5, and 10xLD of the strains (PAO1, PAK, and R), and microbial counts were measured in the skin, liver, spleen, and kidney of the studied mice.

Results: Results showed that the antibody titre (total IgG) was significantly increased by injection of 10 μg of chimeric protein in the experimental groups compared to the control groups. The antibody survival titre was high until 235 days after administration of the second booster. The survival rate of the mice infected with 10xLD was significantly increased and the number of bacteria was reduced, especially in the internal organs (kidney, spleen, and liver) compared to the mice immunized with any of the OprF, OprI, and PcrV proteins alone.

Conclusion: The findings of our study revealed that the chimeric protein is a promising vaccine candidate for control of the infection.
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http://dx.doi.org/10.2147/IDR.S244081DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7294051PMC
June 2020

In-Silico Analysis and Protective Efficacy of the PcrV Recombinant Vaccine against Pseudomonas Aeruginosa in the Burned and PA-Infected BALB/c Mouse Model.

Iran J Immunol 2020 Jun;17(2):121-136

Department of Microbiology, Karaj Branch, Islamic Azad University, Karaj, Iran.

Background: Pseudomonas aeruginosa is considered as the most severe cause of infections in burn patients and pneumonia infections.

Objective: To study the protective effects of recombinant protein vaccine harboring the PcrV of P. aeruginosa in the mouse model of burn and respiratory infections.

Methods: Recombinant protein vaccine harboring the PcrV was expressed in the E. coli BL-21 strain. Mice were immunized with the purified recombinant protein, and the antibody titer was measured in the sera obtained from the immunized mice. Immunized and control mice were challenged by active and passive immunization. The microbial counts in the lung, skin, liver, spleen, and kidney were compared with the control mice.

Results: Bioinformatics analysis indicated that the PcrV protein was conserved in 1552 clinical and environmental isolates. Also, the isoelectric point (pI), molecular weight, and Grand Average of Hydropathy (GRAVY) score were analyzed. Mice were injected with recombinant protein, and serum from immunized mice reacted strongly with recombinant antigen at a dilution of 1:64000. The survival rate of mice infected with 5xLD50 of the P. aeruginosa increased significantly up to 75% in the standard strains (PAO1 and PAK), and the number of bacteria, especially in the internal organs (kidney, spleen, and liver) significantly reduced compared to the mice immunized with placebo.

Conclusion: Our results demonstrated that the PcrV protein could be an effective candidate vaccine for the generation of antibody response against P. aeruginosa infection.
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http://dx.doi.org/10.22034/iji.2020.85590.1718DOI Listing
June 2020

Type I pili, CsuA/B and FimA induce a protective immune response against Acinetobacter baumannii.

Vaccine 2020 07 27;38(34):5436-5446. Epub 2020 Jun 27.

Department of Biology, Shahed University, Tehran Iran; Molecular Microbiology Research Center, Shahed University, Tehran Iran. Electronic address:

Background: Acinetobacter baumannii, a nosocomial pathogen, is considered as a common cause of hospital and community-acquired infections. Emerging multidrug-resistance in this pathogen followed by subsequent problems in treatment has been increasing to alarming levels that warrant investigation of new therapeutic approaches. One strategy to reduce antibiotic resistance is to use of vaccines. Although there is no vaccine currently in development for this pathogen, different attempts have been made to develop one.

Methods: In this study, we used two different recombinant pilus proteins (CsuA/B and FimA) either singly or in combination to evaluate protective efficacy against A. baumannii in lethal and sub-lethal murine sepsis models.

Findings: Active immunization with recombinant proteins in combination elicited high levels of IgG antibody after the first immunization and provided 62% (five of eight mice; p < 0·001) protection against a lethal dose (1·2 × 10 CFU) of A. baumannii along with efficient clearance of bacteria in internal organs viz. spleen, liver, and lungs at sub-lethal challenge. Immunization with CsuA/B alone conferred partial protection as demonstrated by low survival rate (three [37%] of eight mice; p < 0·05) after lethal challenge and reduction of bacteria in internal organs of the mice after 24 h post-sub-lethal infection. Immunization with FimA, in comparison to CsuA/B, showed better protection (four [50%] of eight mice; p < 0·01) and reduction in CFU after 14 h.

Interpretation: Our results showed that pilus proteins in combination as a single immunogen could potentially impart protection against A. baumannii.

Funding: Shahed University.
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http://dx.doi.org/10.1016/j.vaccine.2020.06.052DOI Listing
July 2020

Zinc solubilization characteristics of efficient siderophore-producing soil bacteria.

Iran J Microbiol 2019 Oct;11(5):419-430

Center of Excellence in Electrochemistry, Faculty of Chemistry, University of Tehran, Tehran, Iran.

Background And Objectives: Iron and zinc are two essential micro-nutrients for plant growth and development. Therefore, isolation of siderophores-producing and zinc-solubilizing rhizobacteria involved in bio-availability of these elements is of great interest.

Materials And Methods: In this study, soil samples collected from slightly alkaline soil types were screened for high levels of siderophore secretion and zinc solubilization.

Results: Among positive colonies, three isolates, named F21A, F37 and F38, were able to secrete siderophore at high levels, ranged between 200 and 300 μM/liter. A close association was observed between siderophore production capability and growth rate as an indicator of active metabolism. Siderophore production was closely correlated with the level of zinc ion released into the medium as well. All three siderophore producing isolates were able to withstand temperature as high as 37°C, high concentration of NaCl (up to 2.5%) and a wide range of initial pH from 6 to 9 while hydrolyzing Zn compounds actively. One of the isolates, F21A, tolerated the presence of 200 mgl of zinc. Biochemical and molecular characteristics are indicative that these isolates are . As experienced in a greenhouse experiment, inoculation with the F21A and F37 isolates significantly increase the plants height, fresh and dry weight of corn with compared to control.

Conclusion: These findings demonstrated that the potential of strains as plants growth promoting rhizobacteria (PGPR) in iron and zinc deficient soils.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7049313PMC
October 2019

Involvement of in the occurrence of community and hospital acquired diarrhea, and its virulence diversity among the stool and the environmental samples.

Int J Environ Health Res 2020 Feb 19:1-11. Epub 2020 Feb 19.

Foodborne and Waterborne Diseases Research Center, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran.

Transmission of along the food chain could cause gastrointestinal infections. To show this involvement, the prevalence, putative virulence genotype, and antibiotic resistance phenotype of isolates from stool of 1482 patients with community and hospital acquired diarrhea were compared with 87 isolates from the environmental samples. The results showed infection with in 3.4% of the cases, while 57.4% of vegetable samples were contaminated. Significantly higher frequency of (98%), (98%), (98%), and (90%), but lower rate of (39.2%), was detected among the stool isolates. Multi-drug resistance (MDR) phenotype was detected in 25.5% and 4% of the stool and vegetable isolates, respectively. A higher rate of studied virulence genes was detected among the MDR strains non-MDR strains. These results indicate as a causative agent of diarrhea either among the hospitalized patients and those with community-acquired diarrhea.
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http://dx.doi.org/10.1080/09603123.2020.1726300DOI Listing
February 2020

Inhibitory effect of probiotic yeast on biofilm formation and expression of α-hemolysin and enterotoxin A genes of .

Iran J Microbiol 2019 Jun;11(3):246-254

Molecular Microbiology Research Center (MMRC), Shahed University, Tehran, Iran.

Background And Objectives: , as an opportunistic pathogen, is the cause of a variety of diseases from mild skin infections to severe invasive infections and food poisoning. Increasing antibiotic resistance in isolates has become a major threat to public health. The use of compounds produced by probiotics can be a solution to this problem. Thus, the purpose of this study was to investigate the effect of on some virulence factors (biofilm, α-hemolysin, and enterotoxin A) of .

Materials And Methods: Supernatant and lysate extracts were prepared from S3 culture. Sub-MIC concentrations of both extracts were separately applied to ATCC 29213 (methicillin-sensitive ; MSSA) and ATCC 33591 (methicillin-resistant ; MRSA) strains. Biofilm formation of these strains was measured by microtiter plate assay and expression level of α-hemolysin and enterotoxin A genes ( and , respectively) using real-time PCR technique.

Results: The supernatant extract has reduced both biofilm formation and expression of and genes, while lysate extract had only anti-biofilm effects. The MRSA strain showed more susceptibility to yeast extracts than MSSA strain in all tests.

Conclusion: The present study exhibited favorable antagonistic effects of S3, as a probiotic yeast, on MSSA and MRSA strains. Based on the findings of this study, the compounds produced by this yeast can be used to control infections; however, further similar studies should be conducted to confirm the findings of the present study.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6711867PMC
June 2019

Genetic and Phylogenetic Characterization of the M Gene of Influenza A Virus Isolated from Iranian Patients.

Iran J Public Health 2019 Mar;48(3):525-530

Molecular Microbiology Research Center, Shahed University, Tehran, Iran.

Background: A few studies have been done on the molecular analysis of Iranian influenza A isolates M gene.

Methods: In 2014, nasal swabs collected from outpatients with clinical symptoms in the hospital clinics of Tehran, Iran were subjected for influenza detection and subtyping using Real-Time RT-PCR. Sequence and phylogenetic analysis performed on four randomly selected isolates from each subtype (H1N1 and H3N2) using neighbor-joining method.

Results: Phylogenetic dendrograms drawn based on M nucleotide sequence of H1N1 isolates showed close relatedness with Omanian isolates while the most isolates of H3N2 have clustered with Kuwait isolates and isolates from outside of geographical location. Amino acid sequence analysis showed S31N substitution in all isolates rendering the virus resistant to adamantanes.

Conclusion: This study determined the sequence identity and phylogenetic relatedness of M gene sequence got from Iranian influenza A isolates to elucidate the modality of relationship of this gene in comparison with its counterparts from other regions.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6570800PMC
March 2019

Frequency distribution, genotypes and prevalent sequence types of New Delhi metallo-β-lactamase-producing Escherichia coli among clinical isolates around the world: A review.

J Glob Antimicrob Resist 2019 12 15;19:284-293. Epub 2019 Jun 15.

Department of Microbiology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran.

Objectives: New Delhi metallo-β-lactamase (NDM)-producing Escherichia coli is perceived as one of the primary multidrug-resistant bacteria causing infections in hospitals and clinics. In this review, we present the frequency distribution, genotypes and most prevalent sequence types (STs) of NDM-producing E. coli among clinical isolates worldwide.

Methods: Several international databases, including Medline, Embase, Scopus and Web of Science, were searched from 2008 to 2018 to identify studies addressing the prevalence of NDM-producing E. coli around the world.

Results: Of 974 records identified from the databases, 110 studies fulfilled the eligibility criteria and were included in this analysis. The prevalence of NDM-producing E. coli was 82.6%, 12.9%, 1.5%, 1.0% and 2.0% in Asia, Europe, America, Africa and Oceania, respectively. The most common reported STs among NDM-producing E. coli were ST101, ST167, ST131, ST405, ST410 and ST648.

Conclusion: The spread of NDM variants among E. coli strains is a serious threat to global public health. In addition, the most prevalent E. coli clonal groups, such as ST101 and ST167, are one of the main causes of E. coli infection in different countries.
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http://dx.doi.org/10.1016/j.jgar.2019.06.008DOI Listing
December 2019

Epidemiological linkage of vancomycin-resistant Enterococcus faecium from different sources in Ahwaz, Iran.

FEMS Microbiol Lett 2019 03;366(6)

Department of Pathobiology, School of Public Health, Tehran University of Medical Sciences, Tehran 1417653761, Iran.

This study was set to determine the genetic linkage and the clonal relationship between vancomycin-resistant Enterococcusfaecium (VREfm) isolates in three hospitals of Ahwaz city. In this study, 1050 samples were collected from various rectal swabs, hands of health care workers, environmental surfaces, medical equipment and 146 enterococci isolates from clinical sources of three hospitals from March to September 2015. Antimicrobial resistance patterns in VREfm were detected by disk diffusion method. Genetic linkages of VREfm strains were investigated by pulse field gel electrophoresis (PFGE) and multilocus sequence typing (MLST) methods. Out of 366 enterococcal isolates, 163 Enterococcus faecium isolates were found to be resistant to vancomycin. PFGE and MLST analysis showed the presence of 79 pulsotypes and 11 sequence types (ST), respectively. In total, 90% of the isolates belonged to clonal complex 17 (CC17). Three new STs were reported for the first time in this study and ST80 was the predominant ST. We found a high prevalence of diverse VREfm with threatening antibiotic resistance patterns in all the studied sources with the dominance of CC17 VREfm strains in Ahwaz hospitals. Also, the results of typing method showed inter- and intra-hospital circulation of VREfm and similar pulsotypes and STs among different sources.
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http://dx.doi.org/10.1093/femsle/fnz062DOI Listing
March 2019

High Rate of Serotype Switching and Genetic Variations Indicates Widespread Recombination Between Clinical and Commensal Penicillin-Nonsusceptible in Tehran.

Microb Drug Resist 2019 Jul/Aug;25(6):865-873. Epub 2019 Feb 20.

3 Department of Microbiology, Pasteur Institute of Iran, Tehran, Iran.

A total of 161 were collected between 2013 and 2015 in Tehran, Iran. The strains were tested for antimicrobial susceptibility and minimum inhibitory concentrations, serotyped, and genotyped by multilocus sequence typing (MLST) and pulsed-field gel electrophoresis (PFGE). Penicillin-binding proteins (PBPs) were also typed by restriction fragment length polymorphism (PBP-RFLP). Out of 161 strains, 32 isolates (20%) were highly resistant to penicillin. The most frequent serotypes among the penicillin-nonsusceptible (PNSP) were 14 (24%), 23F (18%), and 19F (17%). RFLP of , , and genes revealed 8, 6, and 7 different patterns, respectively. Analysis of 93 PNSP isolates displayed 80 PFGE types with 8 common types constituting 21 (23%) isolates. The remaining 72 isolates (77%) were single types. MLST indicated a high degree of genetic diversity among the 93 PNSP with 36 different sequence types. Six internationally known penicillin resistant clones were identified in our isolates among which Spain-1 (ST81), Spain-2 (ST90), and Spain-3 (ST156) were the predominant clones. The results indicated international identifiable clones of especially Spain-1 with high penicillin resistance could play a major role in spread of antimicrobial resistance in Iran. The extensive sequence variation in PBP2x, PBP2b, and PBP1a in resistant strains of clinical and commensal was suggestive of a widespread homologous recombination within populations.
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http://dx.doi.org/10.1089/mdr.2018.0336DOI Listing
December 2019

Molecular Characterization of a Fungus Producing Membrane Active Metabolite and Analysis of the Produced Secondary Metabolite

Iran Biomed J 2019 03 16;23(2):121-8. Epub 2018 Sep 16.

Drug Design and Bioinformatics Unit, Medical Biotechnology Department, Biotechnology Research Center, Pasteur Institute of Iran, Tehran, Iran.

Background: The majority of studies on soil Aspergillus concern the isolation and characterization of the antimicrobial compounds produced by this organism. Our previous studies indicated an isolated Aspergillus strain soil to be of interest, and this subject is further investigated here.

Methods: Soil samples of various locations in Iran were collected. Extract from Aspergillus sp. culture was obtained using ethyl acetate fractionation. Antimicrobial activity testing was performed using broth microdilution assay against Escherichia coli, Candida albicans, and Staphylococcus aureus microorganisms. One metabolite PA3-d10 was isolated from these active extracts and identified using thin layer chromatography, preparative thin-layer chromatography, HPLC, 1HNMR (proton nuclear magnetic resonance), 2D NMR, and LC-MS (liquid chromatography-mass spectrometry).

Results: According to morphological and biochemical properties as well as ITS rDNA sequencing, we identified an isolate of Aspergillus flavus. The ethyl acetate fraction of the fermentation medium containing membrane active metabolites showed antimicrobial effects against different bacterial and yeast indicator strains. One metabolite from these active extracts was finally identified.

Conclusion: Membrane active fraction produced by Aspergillus strain in this research demonstrated antimicrobial activities against bacteria and yeast strains. Therefore, this metabolite can be considered as a potential antimicrobial membrane active agent.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6707112PMC
March 2019

Simultaneous Optimization of the Production of Organic Selenium and Cell Biomass in by Plackett-Burman and Box-Behnken Design.

Iran J Pharm Res 2018 ;17(3):1081-1092

Department of Genetics and Molecular Biology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran.

Selenium (Se) as a vital trace element has many biological activities such as anti-inflammation and anti-oxidation. Selenomethionine as an organic selenium plays a vital role in the response to oxidative stress. At present, is one of the best microorganisms that has the ability to accumulate selenium. Production of Seleno-yeast was done by growing in the presence of water soluble selenium salt (NaSeO) as a part of the medium. The yield of selenium biotransformation and yeast biomass can be improved by optimizing the process conditions in two steps. First, the effects of several culture parameters (culture conditions and culture media) were studied using the Plackett-Burman design. After that, determining the optimum levels of the effective parameters was performed by Box-Behnken response surface methodology. Optimization of the conditions was performed with the aim of simultaneously optimizing the biomass and selenium biotransformation. In this investigation, the effect of the eleven culture parameters was studied with Plackett-Burman design. Then, four significant culture parameters such as glucose concentration, aeration, selenium concentration, and temperature were optimized with Box-Behnken response surface methodology.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6094416PMC
January 2018

Screening and characterization of probiotic criteria of and strains.

Iran J Microbiol 2018 Apr;10(2):123-131

Molecular Microbiology Research Center (MMRC), Faculty of Medicine, Shahed University, Tehran, Iran.

Background And Objectives: Probiotics are defined as live micro-organisms conferring a health benefit on the host. Although most probiotics are bacteria, some yeasts such as and , has been found to have effective probiotic properties. The objective of this study was to isolate and identify indigenous and yeast strains and to compare some probiotic characteristics between these two strains .

Materials And Methods: Strains were isolated on yeast glucose chloramphenicol agar medium from 205 samples and identified by morphological, physiological and biochemical assays. The effects of different conditions such as pH and temperature on the survival and growth of the isolates were studied. In addition, resistance to acidic pH (1.5, 2, 3 and 5), pepsin and different concentrations of bile salts (1%, 3% and 5%), as well as proteolytic, lipolytic and hemolytic activity of selected isolates were assessed. Finally, the best isolates were selected for investigation of their viability in samples of dairy products.

Results: 126 isolates were identified using biochemical and molecular techniques as yeast strains. Five isolates were found to have effective probiotic properties, belonging to (S97, S101 and S106) and (S28, S34). These isolates were able to grow at 37°C, pH=1.5, withstand to concentration of 5% oxbile and pepsin and exhibit the proteolytic activity. The isolates of showed better viability in dairy (yogurt).

Conclusion: In the comparative experiments, the isolates of showed better probiotic potentials.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6039453PMC
April 2018

Conserved OprF as a Selective Immunogen against .

Iran J Pathol 2017 1;12(2):165-170. Epub 2017 Apr 1.

Dept. of Physiology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran.

Background & Objectives: Due to the importance of in severe inpatient infections and high mortality, the need for an efficient vaccine against these bacteria is increasing. In this regard, the general outer membrane porin of the most problematic microorganism , outer membrane protein F (OprF), is a good vaccine candidate.

Methods: The databank of NCBI was used to retrieve protein sequences recorded for OprF in The current study aimed at investigating the conservation of the OprF in 150 reference sequences, clinical, and environmental strains of from different countries via bioinformatic tools.T-COFFEE and PRALINE software were used for alignment.

Results: Of these, 134 strains were isolated from clinical specimens and other strains from environmental samples. Evaluation of alignment by the mentioned software clearly showed that this protein was conserved. Antigenicity and grand average of hydropathicity were favorable.

Conclusion: Conservation of OprF in all pathogenic and environmental strains of indicated that it can be considered as a good immunogen; however, the protectivity of OprF should be validated experimentally.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5831073PMC
April 2017

How to Assess Quality of Research in Iran, From Input to Impact? Introduction of Peer-Based Research Evaluation Model in Iran.

Arch Iran Med 2017 Nov 1;20(11):680-685. Epub 2017 Nov 1.

Deputy of Research and Technology, Ministry of Health and Medical Education, Tehran, Iran.

Background: Research evaluation is a systematic and objective process to measure relevance, efficiency and effectiveness of research activities, and peer review is one of the most important tools for assessing quality of research. The aim of this study was introducing research evaluation indicators based on peer reviewing.

Methods: This study was implemented in 4 stages. A list of objective-oriented evaluation indicators were designed in 4 axes, including; governance and leadership, structure, knowledge production and research impact.

Results: The top 10% medical sciences research centers (RCs) were evaluated based on peer review. Adequate equipment and laboratory instruments, high quality research publication and national or international cooperation were the main strengths in medical sciences RCs and the most important weaknesses included failure to adhere to strategic plans, parallel actions in similar fields, problems in manpower recruitment, knowledge translation & exchange (KTE) in service providers and policy makers' levels.

Conclusion: Peer review evaluation can improve the quality of research.
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November 2017

An integrative in silico approach to the structure of Omp33-36 in Acinetobacter baumannii.

Comput Biol Chem 2018 Feb 12;72:77-86. Epub 2018 Jan 12.

Chemical Injuries Research Center, Baqiyatallah University of Medical Sciences, Tehran, Iran.

Omp33-36 in A. baumannii, a bacterium causing serious nosocomial infections, is a virulence factor associated with the pathogen metabolic fitness as well as its adherence and invasion to human epithelial cells. This protein is also involved in interaction of the bacteria with host cells by binding to fibronectin. Moreover, Omp33-36 renders cytotoxicity to A. baumannii in addition to inducing apoptosis and modulation of autophagy. In the present study, an integrated strategy is launched to pierce into the 3D structure of Omp33-36 protein. The signal peptide within the sequence was determined, then, topology as well as secondary and tertiary structures of the protein were predicted. The mature protein assigned as a 14-stranded barrel in which residues 1-19 is removed as signal peptide. The obtained 3D models were evaluated in terms of quality; and then, served as queries to find similar protein structures. The hits were analyzed regarding topology among which 14-stranded were considered. The most qualified model was refined and then its sequence aligned to its counterpart similar structure protein (CymA from Klebsiella oxytoca). The determined structure of Omp33-36 could justify its porin function and carbapenem-resistance associated with the loss of this protein.
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http://dx.doi.org/10.1016/j.compbiolchem.2018.01.003DOI Listing
February 2018

Comprehensive genomic analysis of a plant growth-promoting rhizobacterium Pantoea agglomerans strain P5.

Sci Rep 2017 Nov 15;7(1):15610. Epub 2017 Nov 15.

Energy and Environmental Biotechnology Department, National Institute of Genetic Engineering and Biotechnology, Tehran, Iran.

In this study, we provide a comparative genomic analysis of Pantoea agglomerans strain P5 and 10 closely related strains based on phylogenetic analyses. A next-generation shotgun strategy was implemented using the Illumina HiSeq 2500 technology followed by core- and pan-genome analysis. The genome of P. agglomerans strain P5 contains an assembly size of 5082485 bp with 55.4% G + C content. P. agglomerans consists of 2981 core and 3159 accessory genes for Coding DNA Sequences (CDSs) based on the pan-genome analysis. Strain P5 can be grouped closely with strains PG734 and 299 R using pan and core genes, respectively. All the predicted and annotated gene sequences were allocated to KEGG pathways. Accordingly,  genes involved in plant growth-promoting (PGP) ability, including phosphate solubilization, IAA and siderophore production, acetoin and 2,3-butanediol synthesis and bacterial secretion, were assigned. This study provides an in-depth view of the PGP characteristics of strain P5, highlighting its potential use in agriculture as a biofertilizer.
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http://dx.doi.org/10.1038/s41598-017-15820-9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5688152PMC
November 2017

Highly conserved exposed immunogenic peptides of Omp34 against Acinetobacter baumannii: An innovative approach.

J Microbiol Methods 2018 01 10;144:79-85. Epub 2017 Nov 10.

Chemical Injuries Research Center, System Biology and poisoning institute, Baqiyatallah University of Medical Sciences, Tehran, Iran.

Omp34, also known as Omp34kDa or Omp33-36 is a virulence factor associated with A. baumannii metabolic fitness or its adherence and invasion to human epithelial cells. This protein is also introduced as a specific antigen which could induce strong antibody responses. In the present in silico study, recent vaccine design strategies such as 'antigen minimization' and 'high epitope density' were invoked to design a soluble immunogen with higher antigenicity. As an advantage, the tools employed in the current study are easily available. Exposed peptides in linear B-cell epitopes were predicted and their conservancy and immunogenicity were evaluated. In this regard, constructs were designed by removal of inappropriate regions. Based on the obtained results the external loops (L1-L7) were exclusively considered of which L3, L6 and L7 were the most appropriate of which the most appropriate were in L3>L6>L7 order while L2 was assigned as an inappropriate peptide. The final construct, named Omp34-4, encompasses three copies of L3, two copies of L6 and L7 and one copy of L1, L4 and L5. The designed construct is predicted to be a soluble antigen with enhanced epitope density and antigenicity. Omp34 is present in >1600 strains of A. baumannii with ≥98% identity. So, it could be applicable in diagnostic kits and an immunotherapy choice against A. baumannii. It could be presumed that co-administration of Omp34-4 and a recently designed OmpA-derived antigen could confer sufficient protection against A. baumannii-associated infections. In vitro and in vivo experiments are needed to confirm all these data. The innovative approach could be generalized to vaccine designs focused on OMPs.
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http://dx.doi.org/10.1016/j.mimet.2017.11.008DOI Listing
January 2018

Methicillin-resistant Staphylococcus aureus (MRSA) in Iran: A systematic review and meta-analysis.

J Glob Antimicrob Resist 2018 03 21;12:96-103. Epub 2017 Sep 21.

Department of Microbiology, Faculty of Science, Islamic Azad University of Lahijan, Gilan, Iran.

Introduction: Methicillin-resistant Staphylococcus aureus (MRSA) is among the most prevalent pathogens causing healthcare-associated infections. Accurate and updated data describing the epidemiology of MRSA are crucial for the development of national policies to control MRSA infection in each country. This study aimed to estimate the prevalence of MRSA in different parts of Iran.

Methods: Several databases, including MEDLINE, Embase, Web of Science and Scientific Information Database (http://www.sid.ir), were searched from 1 January 2000 to 31 March 2016 to identify studies addressing the frequency or prevalence of MRSA in Iran. Comprehensive Meta-Analysis software v.2.2 was used to analyse the data.

Results: Of the 725 records identified from the databases, 31 studies fulfilled the eligibility criteria. The analyses showed that the frequency of MRSA infections was 43.0% (95% confidence interval 36.3-50.0%) among confirmed S. aureus isolates. Further stratified analyses indicated that the prevalence of MRSA was higher in studies performed after the year 2000.

Conclusions: Since a high rate of MRSA infections was seen in this analysis, regular surveillance of hospital-associated infections, monitoring of antibiotic sensitivity patterns, and formulation of definite antibiotic policy may facilitate more accurate action for the prevention and control of MRSA.
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http://dx.doi.org/10.1016/j.jgar.2017.09.006DOI Listing
March 2018

Isolation of indigenous Glutathione producing strains.

Iran J Pathol 2016 ;11(4):354-362

Molecular Microbiology Research Center, Shahed University, Tehran, Iran.

Background: Glutathione (GSH) is a non-protein thiol compound, which plays an important role in the response to oxidative stress and nutritional stress. The aim of this study was to isolate indigenous strains capable of effectively produce GSH.

Methods: One hundred-twenty sweet fruit samples were collected. The strains were isolated on yeast glucose chloramphenicol (YGC) agar medium and identified. The isolates were evaluated for GSH producing on yeast malt (YM) medium. Concentration of glutathione was investigated by recording absorbance of all samples at wavelength 412 nm (Ellman's method). In addition, optimization of glucose and peptone concentration in culture medium and the effects of various environmental conditions such as temperature (20-35 °C), agitation rate (150-250 rpm), and initial pH (4.0-6.0) were assessed on producing of GSH.

Results: From 120 samples, 80 isolates were identified by morphological, biochemical and molecular tests as . Five isolates were capable to produce effectively GSH. The optimal culture conditions were agitation rate, 200 rpm; temperature, 30 °C; initial pH, 6; glucose, 30 g/l; and peptone concentration, 5 g/l. In optimal conditions, the amount of derived glutathione was improved compared to YM basal medium and highest GSH concentration (296.8 mg/l) was obtained after cultivation with shaking for 72 h.

Conclusion: The possibility of obtaining cells with a high GSH intracellular content can be considered an interesting opportunity of furthering the range of application and utilization of this molecule.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5563933PMC
January 2016

Diarrheagenic pathotypes frequency in Khuzestan province of Iran.

Iran J Microbiol 2016 Dec;8(6):352-358

Molecular Microbiology Research Center, Shahed University, Tehran, Iran.

Background And Objectives: Diarrheagenic (DEC) is an emerging agent among pathogens that causes diarrhea. Studies showed that diarrheagenic such as enterohaemorrhagic (EHEC), enteroaggregative (EAEC), enteropathogenic (EPEC), enteroinvasive (EIEC), enterotoxigenic (ETEC), diffusely adhering (DAEC) and shiga toxin producing (STEC) strains are among the most frequent causative agents in acute diarrhea. The aim of this study was to determine the frequency of DEC pathotypes in Khuzestan province.

Materials And Methods: Stool samples were collected from patients with diarrhea in Khuzestan province of Iran. strains were isolated using conventional culture and standard biochemical tests. The polymerase chain reaction (PCR) technique was used to detect presence of virulence genes, i.e; , 1 and 2 for EHEC, and for EPEC, and for ETEC, for EAEC, for EIEC, 1 and 2 for STEC.

Results: Altogether, 200 stool samples were obtained from patients, of which 158 (79%) were positive for . DEC was identified in 127 (63%) of stool samples, which frequency of each pathotypes were as follows: atypical EPEC 49 (39%), typical EPEC 1 (0.7%), STEC 50 (39.3%), ETEC 21 (16.3%), EAEC 5 (4.0%) and EIEC 1 (0.7%). Most frequent etiological agents of diarrhea in Khuzestan province of Iran were STEC and EPEC.

Conclusion: Our findings showed DEC had been agent of diarrhea in Khuzestan. This finding provides evidence that effort should be made to estimate the burden of infection by the etiological agent for better medical approach and should raise notification about antibiotic resistance among bacterial infection.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5420388PMC
December 2016

In silico design of an immunogen against Acinetobacter baumannii based on a novel model for native structure of Outer membrane protein A.

Microb Pathog 2017 Apr 27;105:201-210. Epub 2017 Feb 27.

Chemical Injuries Research Center, Baqiyatallah University of Medical Sciences, Tehran, Iran.

Outer membrane protein A (OmpA) is the most promising vaccine candidate against one of the most successful nosocomial pathogens, A. baumannii. Despite advantages of the antigen, its cytotoxicity could be considered as a challenge in clinical trials. In order to improve this effective immunogen, rational vaccine design strategies such as structure-based vaccinology should be assessed. However, native structure of OmpA remains controversial. The present study is conducted to address the native structure of OmpA; then, a novel immunogen with lower toxicity and higher antigenicity was designed based on structural vaccinology. Various bioinformatic and immunoinformatic tools were harnessed to perform analyses such as topology, secondary structure, and tertiary structure predictions as well as B-cell epitope predictions. A novel 12-stranded model is suggested for OmpA. K and K were substituted by Alanine, "NADEEFWN" sequence was replaced by "YKYDFDGVNRGTRGTSEEGTL", Position 1-24 at the N-terminus and the C-terminal sequence "VVQPGQEAAAPAAAQ" were removed. The designed construct has more epitope density and antigenic properties with higher immunogenicity while its cytotoxicity is decreased. Moreover, this single cross-protective antigen could trigger antibodies rendering protection against two important nosocomial pathogens i.e. Pseudomonas aeruginosa and A. baumannii.
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http://dx.doi.org/10.1016/j.micpath.2017.02.028DOI Listing
April 2017