Publications by authors named "Fatemeh Fallah"

58 Publications

Diagnosis of latent tuberculosis infection among pediatric household contacts of Iranian tuberculosis cases using tuberculin skin test, IFN- γ release assay and IFN-γ-induced protein-10.

BMC Pediatr 2021 Feb 11;21(1):76. Epub 2021 Feb 11.

Pediatric Infections Research Center (PIRC), Research Institute for Children's Health (RICH), Shahid Beheshti University of Medical Sciences, Tehran, Iran.

Background: Although the World Health Organization has recommended the diagnosis and prophylactic treatment of latent tuberculous infection (LTBI) in child household contacts of tuberculosis (TB) cases, the national programs in high-burden TB regions rarely implement adequate screening of this high-risk group, mainly because of resource limitations. We aimed to evaluate the prevalence of LTBI among pediatric household contacts of TB cases in two high-burden provinces in Iran.

Methods: We conducted a cohort study in children who had been in household contact with a TB index. All subjects were assessed for active TB disease. For LTBI diagnosis, tuberculin skin test (TST) and QuantiFERON®-TB Gold Plus (QFT-Plus) were performed at the time of the index TB case diagnosis, as well as, 3, 12, and 18 months, if the first results were negative. In addition, interferon-γ-induced protein-10(IP-10) concentrations were measured for all participants.

Results: A total of 230 children were enrolled, who had contact with an index TB case. Three contacts were diagnosed with active TB. According to the TST/QFT-Plus results, 104 (45.2%) children were identified with LTBI during our study. Significantly increased IP-10 levels were found in LTBI patients compared to healthy contacts. Accordingly, more than 50% of LTBI contacts and about 10% of healthy contacts were considered as IP-10-positive.

Conclusion: This study alarmingly illustrates a high prevalence of LTBI among Iranian children exposed to TB cases. We, therefore, emphasize that the children living in close contact with an infectious TB case should be screened effectively and receive prophylactic therapy.
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http://dx.doi.org/10.1186/s12887-021-02524-3DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7877026PMC
February 2021

Detection and characterization of Enterobacteriaceae family members carried by commensal Rattus norvegicus from Tehran, Iran.

Arch Microbiol 2021 Jan 1. Epub 2021 Jan 1.

Department of Epidemiology and Biostatistics, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.

Wild rats are known to carry different microorganisms and are considered a reservoir of zoonotic pathogens worldwide. The urban rats were collected from five districts of Tehran and Gram-negative bacteria (GNB) were isolated from fecal samples and were identified using classical biochemical tests. The antibiotic susceptibility patterns of isolated bacteria were determined by Kirby-Bauer disk diffusion method, the results of which were interpreted in line with CLSI guideline. The frequency of antibiotic-resistant genes was identified using multiplex-PCR. Moreover, PCR method was used to identify the frequency of Escherichia coli O157:H7 and main categories of diarrheagenic E. coli including EPEC, ETEC, EIEC, EAEC, and STEC pathotypes. A total of 100 Rattus norvegicus were trapped and fecal samples were collected. Overall, 72 fecal samples were positive for GNB. E. coli (n = 46/72) had the highest frequency among the isolated GNB. Among E. coli isolates, the highest and lowest resistance rates belonged to ampicillin (56.5%) and ceftriaxone (0%), respectively. Klebsiella spp. was 100% resistant to imipenem, and streptomycin (0%) was the most effective antimicrobial agent on Klebsiella spp. Among surveyed genes, bla (95.8%) and bla (58.3%) had the highest frequency, while bla, and bla were not detected among Enterobacteriaceae. Herein, O157: H7 serotype was not detected and aEPEC (87%) was the most common pathotype detected. Results suggested that rodents might be a reservoir of antimicrobial-resistant pathogens and rodent control along with implementation of surveillance programs should be considered as a critical priority for urban health.
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http://dx.doi.org/10.1007/s00203-020-02126-0DOI Listing
January 2021

Survey of various carbapenem-resistant mechanisms of and isolated from clinical samples in Iran.

Iran J Basic Med Sci 2020 Nov;23(11):1396-1400

Pediatric Infections Research Center, Research Institute for Children's Health, Shahid Beheshti University of Medical Sciences, Tehran, Iran.

Objectives: and resist antibiotics by different intrinsic and acquired mechanisms. This study aims to define various carbapenem-resistant mechanisms of isolated and from nine different provinces of Iran.

Materials And Methods: In this cross-sectional study, all carbapenem-resistant and samples from nine provinces of Iran on a one-year time horizon were gathered. Modified Hedge Test (MHT) and Carba NP-Test were applied to the identification of producing-carbapenemase strains. The most important carbapenemase genes recognized by PCR and gene overexpression of the efflux pump were surveyed by efflux pump inhibitors (EPIs) and confirmed by Real-Time PCR.

Results: Twenty-one percent and 43.5% of and isolates were resistant to carbapenem, respectively. MHT and Carba-NP tests identified 21% and 11% carbapenemase-producing strains in these Gram-negative bacteria, respectively. NDM-1 was the most prevalently detected carbapenemase in ; OXA-51 and OXA-23 were the most significant genes in . EPIs identified active efflux pumps in 20% and 28% of and , respectively. Real-time PCR confirmed gene overexpression of efflux pumps in 54% and 30% of positive EPIs in and , respectively.

Conclusion: and may become multi-drug-resistant (MDR) and Extensively Drug-Resistant (XDR) strains and cause a high rate of mortality and morbidity. Thus, it is of necessity to prohibit the spread of antibiotic-resistant strains in hospitals.
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http://dx.doi.org/10.22038/IJBMS.2020.44853.10463DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7671419PMC
November 2020

Evaluation of Blood and Liver Cytotoxicity and Apoptosis-necrosis Induced by Nanochelating Based Silver Nanoparticles in Mouse Model.

Iran J Pharm Res 2020 ;19(2):207-218

Department of Research and Development, Sodour Ahrar Shargh Company, Tehran, Iran.

This study aimed to evaluate the and biological activities of newly synthesized nanochelating based silver nanoparticles (AgNPs) in mouse model. Nanochelating technology was used to design and synthesize the AgNPs. The animals studies were including the lethal dose (LD50) determination by the intraperitoneal administration in mice, and determination of liver enzymes levels and hematological parameters. Flow cytometry analysis was used to quantitatively determine apoptosis and necrotic cells . The NPs A and NPs B have LD50 = 250 mg/kg and LD50 = 350 mg/kg, respectively and classified as non-toxic. In general, minor alterations were observed in levels of liver enzymes as indicative of liver damage. For blood parameters several factors associated with significant changes in AgNPs treated animals. Regarding animals weight, combination therapy showed more effective to maintain animals weight losses after infection. Flow cytometry results showed that AgNPs induced cell apoptosis-necrosis depends on AgNP size, concentration and exposure time. Cells damage due to AgNPs (A) with lower size (20-25 nm) were relatively more than cells exposed to AgNPs (B) (30-35 nm). The findings support the potent antibacterial activities of nanochelating based AgNPs. Also, the present study showed that nanochelating based AgNPs induce a moderate level of apoptosis/necrosis in mice, and affected several clinical parameters like blood parameters, liver enzymes, and body weight with no definite signs of toxicity.
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http://dx.doi.org/10.22037/IJPR.2020.1101026DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7667554PMC
January 2020

Serosurvey and molecular detection of the main zoonotic parasites carried by commensal population in Tehran, Iran.

Trop Med Health 2020 22;48:60. Epub 2020 Jul 22.

Pediatric Infections Research Center, Research Institute for Children's Health, Shahid Beheshti University of Medical Sciences, P.O. Box 15468-15514, Tehran, Iran.

Background: are reservoirs for transmission of various zoonotic parasites, and they have become a threat to public health worldwide. Given the large number and the significant presence of throughout the city of Tehran, this study aims to assess the frequency of zoonotic parasites carried by commensal rodents wandering in Tehran, Iran. The study considered the north, south, west, east, and center regions of Tehran for the purposes of this study. The serological tests were applied in order to detect effective antibodies against (), spp., and spp. using a commercial qualitative rat ELISA kit. The frequency of () was surveyed by using the conventional PCR method. Furthermore, nested PCR was employed to detect the presence of spp. and spp. in commensal dispersed in Tehran.

Results: Approximately, 76% of the 100 tested were infected with at least one zoonotic parasite, indicating the significant frequency of parasites within the study areas. Seroreactivity against , spp., and spp. was detected in 5%, 0%, and 1% of the tested, respectively. DNA was detected in 32 out of 100 (32%) . In addition, spp. and spp. DNA were found in 18 out of 100 (18%) and 76 out of 100 (76%) investigated, respectively. with 15% and with 70% had the highest frequency of parasites among the collected from the western and northeastern regions of Tehran, respectively. Moreover, spp. with 95% and spp. with 30% had the highest frequency in the east and center districts, respectively.

Conclusion: The findings showed a wide geographical dissemination of spp., , and spp. in within five districts of Tehran. In contrast, other parasites such as spp. infection were rarely detected in populations. No evidence for the circulation of spp. was found in this study.
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http://dx.doi.org/10.1186/s41182-020-00246-3DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7374959PMC
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

Exploiting yoeB-yefM toxin-antitoxin system of Streptococcus pneumoniae on the selective killing of miR-21 overexpressing breast cancer cell line (MCF-7).

J Cell Physiol 2020 03 20;235(3):2925-2936. Epub 2019 Sep 20.

Cellular and Molecular Biology Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.

Toxin-antitoxin (TA) systems are two-component genetic modules widespread in bacterial and archaeal genomes, in which the toxin module is rendered inactive under resting conditions by its antitoxin counterpart. Under stress conditions, however, the antitoxin is degraded, freeing the toxin to exert its lethal effects. Although not evolved to function in eukaryotes, some studies have established the lethal activity of these bacterial toxins by inducing apoptosis in mammalian cells, an effect that can be neutralized by its cognate antitoxin. Inspired by the way the toxin can become active in eukaryotes cells, we produced an engrained yoeB-yefM TA system to selectively kill human breast cancer cells expressing a high level of miR-21. Accordingly, we generated an engineered yefM antitoxin gene with eight miR-21 target sites placed in its 3'untranslated region. The resulting TA system acts autonomously in human cells, distinguishing those that overexpress miR-21, killed by YoeB, from those that do not, remaining protected by YefM. Thus, we indicated that microRNA-control of the antitoxin protein of bacterial TA systems constitutes a novel strategy to enhance the selective killing of human cancer cells by the toxin module. The present study provides significant insights for developing novel anticancer strategies avoiding off-target effects, a challenge that has been pursued by many investigators over the years.
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http://dx.doi.org/10.1002/jcp.29198DOI Listing
March 2020

WITHDRAWN: Molecular detection and genotyping of bacterial and viral meningitis common causative agents by multiplex real-time PCR in Iran.

J Microbiol Methods 2019 Sep 2:105715. Epub 2019 Sep 2.

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

This article has been withdrawn at the request of the editor. The Publisher apologizes for any inconvenience this may cause. The full Elsevier Policy on Article Withdrawal can be found at https://www.elsevier.com/about/our-business/policies/article-withdrawal.
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http://dx.doi.org/10.1016/j.mimet.2019.105715DOI Listing
September 2019

Evaluation of Nano-curcumin effects on expression levels of virulence genes and biofilm production of multidrug-resistant isolated from burn wound infection in Tehran, Iran.

Infect Drug Resist 2019 23;12:2223-2235. Epub 2019 Jul 23.

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

Background: is considered as one of the most important pathogens, and high antibiotic resistance to has become an alarming concern. This study attempts to further improve curcumin solubility and stability by producing the involved nanoparticle and investigate the effect of this nanoparticle on those virulence genes of in pathogenicity and biofilm formation.

Methods: In this study, the curcumin nanoparticles were synthesized and characterized, and the antibacterial and antibiofilm effects of Nano-curcumin and curcumin were investigated by microdilution broth and microtiter plate, respectively. In addition, cytotoxic effect of Nano-curcumin on human epithelial cell lines (A549) was determined. The effects of Nano-curcumin on virulence genes, and (efflux pumps), (adhesion), (negative regulator of MexCD-OprJ), and (biofilm formation) were determined using real-time quantitative PCR.

Results: Synthesized Nano-curcumins were soluble in water, which inhibited the growth of multidrug-resistant (MDR) at 128 µg/mL, whereas it was inhibited at 256 µg/mL for soluble curcumin in DMSO. Sub-inhibitory concentrations of Nano-curcumin reduced biofilm formation and, at 64 μg/mL, disrupted 58% of the established bacterial biofilms. In addition, curcumin nanoparticle downregulated the transcription of virulence genes except and exerted no cytotoxic effect on human epithelial cell lines (A549).

Conclusions: Results suggest that Nano-curcumin could be potentially used to reduce virulence and biofilm. However, in vivo studies with respect to an animal model are necessary to validate these results.
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http://dx.doi.org/10.2147/IDR.S213200DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6664860PMC
July 2019

Evaluating the antimicrobial resistance patterns among major bacterial pathogens isolated from clinical specimens taken from patients in Mofid Children's Hospital, Tehran, Iran: 2013-2018.

Infect Drug Resist 2019 17;12:2089-2102. Epub 2019 Jul 17.

Pediatric Infections Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.

Background: This study evaluates the epidemiology and antimicrobial resistance profile of Gram-negative bacteria (GNB) and Gram-positive bacteria (GPB) isolated from clinical specimens in children admitted to Mofid Children's Hospital.

Methods: This was a retrospective study of the patients' clinical specimens collected from January 2013 until the end of December 2018. All specimens were evaluated to determine the presence of infection-causing agents using a BACTEC 9120 blood culture. Isolation and identification of bacterial strains were performed using conventional biochemical tests. Antibiotic resistance was determined using Kirby-Bauer disk diffusion and broth microdilution methods. Results were interpreted according to CLSI and EUCAST.

Results: A total of 1130 different pathogenic bacteria were detected from 14,690 different clinical specimens and the overall detection rate was 7.7% (1130/14,690). Among bacterial pathogen isolated from clinical specimens, 55% (n=622) were GNB and 45% (n=508) were GPB. The predominant GNB isolates were spp., spp., spp., respectively. Among GPB, CoNS was the most frequent and spp. was found to have low levels of resistance to linezolid. In GNB, most and were ceftriaxone resistant. was found to have low levels of resistance to levofloxacin and ciprofloxacin.

Conclusions: Our findings revealed that the resistance rate among GNB and GPB associated with different infections in children is very high. These results suggest a constant screening and follow-up programs for the detection of antibiotic resistance, and it also suggests to develop antimicrobial stewardship programs in Tehran, Iran.
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http://dx.doi.org/10.2147/IDR.S215329DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6645606PMC
July 2019

Role of efflux pumps in reduced susceptibility to tigecycline in .

New Microbes New Infect 2019 Jul 16;30:100547. Epub 2019 Apr 16.

Pediatric Infection Research Center, Research Institute for Children Health, Shahid Beheshti University of Medical Sciences, Tehran, Iran.

is an important human pathogen responsible for a various type of infections. These bacterial strains are generally resistant to numerous antibiotics. Therefore, eradication of such strains is problematic and related to high mortality. We investigated the effect of cyanide 3-chlorophenylhydrazone (CCCP) efflux pump inhibitor in tigecycline-resistant strains of In a cross-sectional study, from July until the end of February 2017, eighty isolates of were recovered. Antimicrobial susceptibility testing against tigecycline was performed by the disc diffusion method and determination of minimum inhibitory concentration by broth microdilution method, according to Clinical and Laboratory Standards Institute guidelines. Active efflux pumps were detected by CCCP as an efflux pumps inhibitor, and the gene expression of some of the resistance/nodulation/division (RND)-type efflux pumps was measured by semiquantitative RT-PCR (qRT-PCR). Antibiotic susceptibility tests in this study showed that 78 of 80 isolates were resistant to tigecycline. The results of phenotypic detection of efflux pumps revealed that 23.07% of tigecycline-resistant isolates can contain active efflux pumps. On the basis of conventional PCR, genes coding for and were detected in 76 (98%) isolates. The results of qRT-PCR showed that the transcript level of the gene increased in 66.6% isolates with CCCP-positive tests and was correlated with tigecycline resistance. The results of this study indicate that RND-type efflux pumps appear to play a significant role in the tigecycline resistance of
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http://dx.doi.org/10.1016/j.nmni.2019.100547DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6541740PMC
July 2019

Characterization of Phenotypic and Genotypic Diversity of Strains Isolated From Selected Hospitals in Iran.

Front Microbiol 2019 29;10:1191. Epub 2019 May 29.

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

is an environmental Gram-negative bacterium that has rapidly emerged as an important nosocomial pathogen in hospitalized patients. Treatment of infections is difficult due to increasing resistance to multiple antibacterial agents. The purpose of this study was to determine the phenotypic and genotypic characterization of isolates recovered from patients referred to several hospitals. A total of 164 clinical isolates of were collected from hospitals in various regions in Iran between 2016 and 2017. Antibiotic susceptibility testing was performed by disc diffusion method and E-test assay according to the Clinical and Laboratory Standards Institute (CLSI) guideline. The ability of biofilm formation was assessed with crystal violet staining and then, biofilm-associated genes were investigated by PCR-sequencing method. The presence of (a metallo-β-lactamase), (a clavulanic acid-sensitive cephalosporinase), and (resistance to Trimethoprim/Sulfamethoxazole), Sm (intrinsic resistance to quinolones), and genes (dihydrofolate reductase enzyme that contributes to trimethoprim resistance) was also examined by PCR-sequencing. Relative gene expression of efflux pump was assessed by real-time PCR. Genotyping was performed using the multi-locus sequencing typing (MLST) and repetitive extragenic palindromic-PCR (Rep-PCR). Isolates were resistant to imipenem (100%), meropenem (96%), doripenem (96%), and ceftazidime (36.58%). Notably, 5 (3.04%) isolates showed resistant to trimethoprim-sulfamethoxazole (TMP-SMX), an alarming trend of decreased susceptibility to TMP-SMX in Iran. Minocycline and levofloxacin exhibited the highest susceptibility of 91.46 and 99.39%, respectively. Using the crystal violet staining, 157 (95.73%) isolates had biofilm phenotype: 49 (29.87%), 63 (38.41%), and 45 (27.43%) isolates were categorized as strong-, moderate- and weak-biofilm producer while 7 isolates (4.26%) were identified a non-biofilm producer. Biofilm genes had an overall prevalence of 145 (88.41%), 137 (83.53%), and 164 (100%) of , , and , respectively. , , , , and resistance genes were detected in 145 (88.41%), 156 (96.12%), 103 (62.80%), 89 (54.26%), and 92 (56.09%) isolates, respectively. None of the isolates were positive for , , and genes. Gene expression analysis showed that efflux system was overexpressed in two out of the five clinical isolates (40%) that showed resistance to TMP-SMX. Most of the isolates were genetically unrelated. Two new sequence types (ST139 and ST259) were determined. Our results showed that TMP-SMX was still an effective antibiotic against . The findings of the current study revealed an increasing prevalence of antibiotic resistance and biofilm genes in clinical isolates in Iran.
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http://dx.doi.org/10.3389/fmicb.2019.01191DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6548850PMC
May 2019

Molecular detection of ALS1, ALS3, HWP1 and SAP4 genes in Candida Genus isolated from hospitalized patients in Intensive Care Unit, Tehran, Iran.

Cell Mol Biol (Noisy-le-grand) 2019 Apr 30;65(4):15-22. Epub 2019 Apr 30.

Pediatric Infection Research Center, Research Institute for Children Health, Shahid Beheshti University of Medical Sciences, Tehran, Iran.

Candida species are considered as one of the important cause of nosocomial and community infections. Candidacies are fourth caused by septicemia in some countries and possess extra cost to the health care system. The aim of this study was survey the presence of virulence factors associated with various candida geniuses in samples which have been collected from the intensive care unit. In this cross-sectional study, various clinical specimens have been collected from patients which hospitalized in the Intensive Care Unit (ICU) of Milad hospital, Tehran, Iran. The species of candida has been determined by CHROM agar. Finally, adherence factors genes and proteinase gene have been detected by PCR. In this research, 100 samples have been collected from patients that colonized with candida. C. albicans (63%) and C.glabrata (19.4%) are the most identified species, respectively. The species of four specimens have been not detected according to the color of CHROM agar candida medium and two different genus of candida has been isolated from 7 patients. The frequency of Als1, Als3, HWP1 and SAP1 genes among C. albicans was (92%), (94%), (95%) and (88%), respectively. The most detected virulence factor was HWP1 and SAP4 was the lowest one. At least two virulence factors have been detected in 95% of different Candida species that can cause invasive fungal properties. These results are important for infection control committee in the hospital because invasive fungal diseases can make a serious problem for patients that hospitalized in ICU.
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April 2019

A Recombinant Snake Cathelicidin Derivative Peptide: Antibiofilm Properties and Expression in .

Biomolecules 2018 10 22;8(4). Epub 2018 Oct 22.

Pediatric Infections Research Center (PIRC), Research Institute for Children Health, Shahid Beheshti University of Medical Sciences, Tehran 1546815514, Iran.

The emergence of antimicrobial resistance among pathogenic microorganisms has been led to an urgent need for antibiotic alternatives. Antimicrobial peptides (AMPs) have been introduced as promising therapeutic agents because of their remarkable potentials. A new modified cathelicidin-BF peptide (Cath-A) with 34 amino acid sequences, represents the potential antimicrobial effects against methicillin-resistant (MRSA) with slight hemolytic and cytotoxic activities on eukaryotic cells. In this study, the effects of Cath-A on , and isolated from medical instruments were studied. Cath-A inhibited the growth of bacterial cells in the range of 8⁻16 μg/mL and 16-≥256 μg/mL for and , respectively. The peptide significantly removed the established biofilms. To display a representative approach for the cost-effective constructions of peptides, the recombinant Cath-A was cloned in the expression vector pET-32a(+) and transformed to . The peptide was expressed with a thioredoxin (Trx) sequence in optimum conditions. The recombinant peptide was purified with a Ni affinity chromatography and the mature peptide was released after removing the Trx fusion protein with enterokinase. The final concentration of the partially purified peptide was 17.6 mg/L of a bacterial culture which exhibited antimicrobial activities. The current expression and purification method displayed a fast and effective system to finally produce active Cath-A for further in-vitro study usage.
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http://dx.doi.org/10.3390/biom8040118DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6315654PMC
October 2018

First detection of efrAB, an ABC multidrug efflux pump in Enterococcus faecalis in Tehran, Iran.

Acta Microbiol Immunol Hung 2019 Mar 24;66(1):57-68. Epub 2018 Sep 24.

4 School of Medicine, Shahroud University of Medical Sciences , Shahroud, Iran.

Enterococcus faecalis is one of the most significant pathogen in both nosocomial and community-acquired infections. Reduced susceptibility to antibiotics is in part due to efflux pumps. This study was conducted on 80 isolates of E. faecalis isolated from outpatients with urinary tract infection during a period of 1 year from April 2014 to April 2015. The antibiotic susceptibility patterns of isolates were determined by the disk diffusion method and presence of efrA and efrB genes was detected by PCR and sequencing. Minimum inhibitory concentrations (MICs) to ciprofloxacin (CIP) were measured with and without carbonyl cyanide 3-chlorophenylhydrazone (CCCP) by broth microdilution. The highest resistance rate was observed to erythromycin (83.3%) and the prevalence of efrA and efrB genes in all E. faecalis isolates was 100%. This study showed that 9 out of 13 (69.2%) ciprofloxacin-resistant isolates became less resistant at least fourfolds to CIP in the presence of efflux pump inhibitor. Our result showed that CCCP as an efflux inhibitor can increase effect of CIP as an efficient antibiotic and it is suggested that efrAB efflux pumps are involved in resistance to fluoroquinolone.
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http://dx.doi.org/10.1556/030.65.2018.016DOI Listing
March 2019

Warning: spread of NDM-1 in two border towns of Iran.

Cell Mol Biol (Noisy-le-grand) 2018 Jul 30;64(10):125-129. Epub 2018 Jul 30.

Pediatric Infections Research Center, Research Institute for Children Health, Shahid Beheshti University of Medical Sciences, Tehran, Iran.

NDM-1 producing gram-negative bacteria can be resistant to every beta-lactam antibiotic, including carbapenem which is one of the last-lines of antibiotic therapy against multi-drug resistant bacteria. This study aimed to detect the metallo-beta-lactamase in the isolated gram-negative bacteria of the Iranian clinical specimens collected from two major cities in Iran. In this cross sectional study 171 Acinetobacter baumannii, 120 Enterobacter spp. and 145 Klebsiella pneumoniae isolated from clinical specimens of two training hospitals in Tabriz and Mashhad were evaluated. Carbapenem resistant screening was performed according to CLSI guide line. The antibiotic susceptibility testing was prepared for carbapenem resistant strains. Then, the metallo-beta- lactamase genes detection was also carried out by PCR assay and confirmed by sequencing. Sixty-eight, 12 and 22 carbapenem resistant Acinetobacter baumannii, Klebsiella pneumoniae and Enterobacter spp. were respectively confirmed, respectively. blaVIM in 9% and blaNDM-1  in 4% of isolated A. baumannii were observed. blaNDM-1 was also detected in 18% and 25% of K. pneumoniae and Enterobacter spp. isolates, respectively. This is the first report of NDM-1 producer A. baumannii and Enterobacter pp. in Iran. NDM-1 producing gram-negative bacteria can be resistant to all beta-lactam antibiotics and cause complicated challenges in health care systems.
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July 2018

Synthesis of the erythromycin-conjugated nanodendrimer and its antibacterial activity.

Eur J Pharm Sci 2018 Oct 25;123:321-326. Epub 2018 Jul 25.

Department of Microbiology, Faculty of Medicine, Kashan University of Medical Sciences, Kashan, Iran. Electronic address:

The development and spread of bacterial resistance to antimicrobial drugs necessitates the need to search for novel and effective antimicrobial agents. In the last few decades, innovative nanomaterials are attracting increasing attention and, among them, dendrimers have shown wide application in the various fields. In the current study, the two generations of an anionic linear- spherical nanodendrimer G1 and G2 were synthetized and compound G2 of nanodendrimer conjugated with erythromycin. The structures of the nanodendrimers were characterized by FTIR spectroscopy, zetasizer, and scanning electron microscopy (SEM). The antibacterial activity of the erythromycin-conjugated nanodendrimer and erythromycin alone were evaluated by the microdilution method against Staphylococcus aureus, S. epidermidis, S. saprophyticus, and Pseudomonas aeruginosa. The size of first and second generation of nanodendrimer, and the erythromycin-conjugated nanodendrimer was 75, 95, and 65.6 nm, respectively. The drug loading percentage of the nanodendrimer conjugates was obtained to be in 35.2%. In our study, the erythromycin-conjugated nanodendrimer showed significantly more bacteriostatic and bactericidal activities against all four studied bacteria than erythromycin alone. Our study's results highlight that the erythromycin-conjugated nanodendrimer is a highly effective agent against Gram positive and negative bacteria. The antibacterial properties of erythromycin combined with the targeting potential of the nanodendrimer can lead to sustained intracellular delivery of therapeutic agent.
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http://dx.doi.org/10.1016/j.ejps.2018.07.051DOI Listing
October 2018

Prevalence of virulence determinants and antibiotic resistance patterns of Enterococcus faecalis strains in patients with community-acquired urinary tract infections in Iran.

Int J Environ Health Res 2018 Dec 25;28(6):599-608. Epub 2018 Jul 25.

f School of medicine , Shahroud University of Medical Sciences , Shahroud , Iran.

The aim of this study was to characterize virulence factors and antibiotic resistance patterns in E. faecalis strains obtained from community-acquired urinary tract infections. A total of 70 E. faecalis isolates from Labbafinejad Hospital in Tehran were collected. Antibiotic resistance and virulence determinants were examined by phenotypic and molecular methods. Among 70 E. faecalis isolates, efba (97.1%), ace (95.7%), and gelE (94.3%) were the most prevalent virulence genes. The most common antibiotic resistance pattern was tetracycline (88.6%) and minocycline (87.1%). Multi-drug resistant phenotype was detected among 10% of them. Our results showed capability of E. faecalis strains for infection of the urinary tract in community. Involvement of virulence determinants in the pathogenesis of community acquired E. faecalis strains was proposed due to their high prevalence rates. Food producing animals were proposed as their environmental reservoirs, due to dominance of tetracycline resistance phenotype among them.
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http://dx.doi.org/10.1080/09603123.2018.1497777DOI Listing
December 2018

Resistant/susceptible classification of respiratory tract pathogenic bacteria based on volatile organic compounds profiling.

Cell Mol Biol (Noisy-le-grand) 2018 Jun 30;64(9):6-15. Epub 2018 Jun 30.

Pediatric Infections Research Center, Research Institute for Children Health, Shahid Beheshti University of Medical Sciences, Tehran, Iran.

Resistance to antibiotics is an emerging and growing threat. To address this threat, attempts are being made by researchers to identify the Volatile Organic Compounds (VOCs) of bacteria. It is believed that unique combinations could be found among the VOCs produced by each microorganism. The current study aimed to identify and compare the VOCs of antibiotic-resistant and standard strains of Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Acinetobacter baumannii and Klebsiella pneumoniae. A polymer of divinylbenzene /carboxen /polydimethylsiloxane was applied for absorption of volatile compounds in headspace bacterial samples in form of a solid phase micro-extraction fiber holder. Gas chromatography-mass spectrometry technique was used for identification of volatile compounds. The analysis of the VOCs indicated that some VOCs appeared only in standard strains while others were common only among resistant strains. Exclusive VOCs to a specific strain were also detected. This study demonstrated that resistant strains of bacteria produced VOCs that were different from those of the standard strains. In addition, VOCs released by bacteria after passing the logarithmic growth phase showed no significant differences. The identification of VOCs can be a precise way to differentiate bacterial species, also it can be said that the VOCs produced by different pathogenic microorganisms can be the suitable biomarkers for their detection.
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June 2018

Human immunodeficiency virus in patients with tuberculous meningitis: systematic review and meta-analysis.

Trop Med Int Health 2018 06 21;23(6):589-595. Epub 2018 May 21.

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

Introduction: Human immunodeficiency virus (HIV)-infected individuals are at increased risk for all forms of extrapulmonary tuberculosis (TB), including tuberculous meningitis (TBM). This study aimed to investigate the frequency of HIV in patients with TBM.

Methods: PubMed, Embase, Web of Science and Cochrane Library were searched for articles including relevant data. Stata version 14.0 (StataCorp, College Station, Texas, USA) was used to analyse the data.

Results: Twenty studies were identified. The pooled frequency of HIV among adult patients with TBM was 38.0% (95% CI: 21.0-57.0; I = 97%). In children (under the age of 15 years), 6.0% (95% CI: 1.0-13.0; I = 0.0%) had HIV infection. In patients with bacterial meningitis other than TBM, 36.0% (95% CI: 19.0-53.0; I = 100%) were HIV-infected.

Conclusions: A relatively high frequency of HIV in patients with TBM was indicated by our study. Establishment of diagnostic criteria and effective treatment strategies for TBM/HIV co-infection are recommended for better management of patients with TBM+HIV.
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http://dx.doi.org/10.1111/tmi.13059DOI Listing
June 2018

Factors affecting the properties of nitrocellulose emulsions: A comparative study.

Carbohydr Polym 2018 Jun 2;189:267-272. Epub 2017 Nov 2.

Department of Polymer Engineering and Color Technology, Amirkabir University of Technology Tehran Polytechnic, 424 Hafez Ave, Tehran 15875-4413, Iran. Electronic address:

In this study the influence of viscosity and chemical nature of dispersed phase, preparation conditions and storage temperature on the properties of nitrocellulose emulsions produced by gel emulsification (G) and direct mechanical emulsification (D) methods were examined. Chemical nature of dispersed phase had no effect on the drop size for both methods; however it had a significant effect on emulsion stability. Viscosity of dispersed phase did not considerably affect drop breakage process in route G, while strongly affected drop breakage in route D. Addition rate had no significant effect on the drop size produced by route D; while for route G high addition rate resulted in catastrophic phase inversion. The drop size produced by route D decreased dramatically by increasing stirring speed, whereas stirring speed had a minimal effect on the drop breakage process in route G. Finally, it was found that emulsion stability was greatly influenced by storage temperature.
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http://dx.doi.org/10.1016/j.carbpol.2017.11.002DOI Listing
June 2018

Enterobacterial repetitive intergenic consensus (ERIC)-PCR analysis as a reliable evidence for suspected Shigella spp. outbreaks.

Braz J Microbiol 2018 Jul - Sep;49(3):529-533. Epub 2018 Feb 8.

Shahid Beheshti University of Medical Sciences, Mofid Hospital, Pediatric Infection Research Center, Tehran, Iran.

Background: Shigellosis remains a serious public health problem and an important cause of morbidity and mortality worldwide. The aim of this study was to characterize fliC and the genetic relatedness of Shigella spp. isolated during a one-year period from children in a suspected outbreak in Tehran, Iran.

Methods And Results: Fifty Shigella spp. were isolated from 3779 stool samples of children with diarrhea (prevalence rate: 1.32%). Among the isolates, 92% were characterized as Shigella sonnei, while 6% and 2% were identified as S. flexneri and S. boydii, respectively. S. dysenteriae was not recovered from the patients. All isolates were negative for fliC except for Shigella standard strains. The enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR) profiles allowed differentiating the 50 isolates into 5 ERIC types, which were grouped into five clusters (ET1-ET5). Computer-assisted clustering of the strains showed a high degree of similarity among the isolates.

Conclusion: In conclusion, given the clonal correlation of the Shigella strains isolated in this study and the lack of fliC among them, we propose that probably a single or limited fliC-defected Shigella clone spread and caused the outbreak.
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http://dx.doi.org/10.1016/j.bjm.2017.01.014DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6066780PMC
October 2018

Bacillus Calmette-Guerin (BCG) vaccine in Iran.

J Clin Tuberc Other Mycobact Dis 2018 May 24;11:22. Epub 2018 Feb 24.

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

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http://dx.doi.org/10.1016/j.jctube.2018.02.001DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6830148PMC
May 2018

The antimicrobial potential of a new derivative of cathelicidin from Bungarus fasciatus against methicillin-resistant Staphylococcus aureus.

J Microbiol 2018 Feb 2;56(2):128-137. Epub 2018 Feb 2.

Skin Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.

Cathelicidins are a family of antimicrobial peptides which exhibit broad antimicrobial activities against antibiotic-resistant bacteria. Considering the progressive antibiotic resistance, cathelicidin is a candidate for use as an alternative approach to treat and overcome the challenge of antimicrobial resistance. Cathelicidin-BF (Cath-BF) is a short antimicrobial peptide, which was originally extracted from the venom of Bungarus fasciatus. Recent studies have reported that Cath-BF and some related derivatives exert strong antimicrobial and weak hemolytic properties. This study investigates the bactericidal and cytotoxic effects of Cath-BF and its analogs (Cath-A and Cath-B). Cath-A and Cath-B were designed to increase their net positive charge, to have more activity against methicillin resistant S. aureus (MRSA). The results of this study show that Cath-A, with a +17-net charge, has the most noteworthy antimicrobial activity against MRSA strains, with minimum inhibitory concentration (MIC) ranging between 32-128 μg/ml. The bacterial kinetic analysis by 1 × MIC concentration of each peptide shows that Cath-A neutralizes the clinical MRSA isolate for 60 min. The present data support the notion that increasing the positive net charge of antimicrobial peptides can increase their potential antimicrobial activity. Cath-A also displayed the weakest cytotoxicity effect against human umbilical vein endothelial and H9c2 rat cardiomyoblast cell lines. Analysis of the hemolytic activity reveals that all three peptides exhibit minor hemolytic activity against human erythrocytes at concentrations up to 250 μg/ml. Altogether, these results suggest that Cath-A and Cath-B are competent candidates as novel antimicrobial compounds against MRSA and possibly other multidrug resistant bacteria.
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http://dx.doi.org/10.1007/s12275-018-7444-5DOI Listing
February 2018

Initial study of three different pathogenic microorganisms by gas chromatography-mass spectrometry.

F1000Res 2017 10;6:1415. Epub 2017 Aug 10.

Department of Biology, Medicinal plants and Drugs Research Institute, Shahid Beheshti University, Tehran, Iran.

: Diagnoses  of  respiratory  tract  infections  usually happen  in  the  late  phase  of  the  disease  and  usually  result  in  reduction  of  the  pathogen  load after broad-spectrum  antibiotic  therapy,  but  not  in eradication of the pathogen.  The  development  of a  non-invasive,  fast,  and  accurate  method  to  detect  pathogens  has  always  been  of  interest  to  researchers  and  clinicians  alike.  Previous studies have shown that bacteria produce organic gases.  The  current  study  aimed  to  identify  the  volatile  organic  compounds  (VOCs)  produced  by three  respiratory  tract  pathogens,  including  ,   and  : The  VOCs  produced  were identified by gas chromatography-mass spectrometry (GC-MS), with  prior  collection  of  microbial  volatile  compounds  using  solid  phase  microextraction  (SPME)  fiber.  The volatile compounds were collected by obtaining bacterial headspace samples. : Results  showed  that  these  three  organisms  have  various  VOCs,  which  were  analyzed  under  different  conditions.  By ignoring common VOCs, some species-specific VOCs could be detected.  The most important VOC of was indole, also some important VOCs produced by   were 2,3-pentandione,  cis-dihydro-α-terpinyl  acetate,  1-decyne,  1,3-heptadiene,  2,5-dimethyl  pyrazine,  ethyl  butanoate  and  cyclohexene,4-ethenyl. Furthermore,  most  of the identified  compounds  by  are  alcohols. : The  detection  of  VOCs  produced  by  infectious  agents  maybe  the  key  to  make   a  rapid  and  precise  diagnosis  of  infection,  but  more  comprehensive  studies  must  be  conducted  in this  regard.
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http://dx.doi.org/10.12688/f1000research.12003.3DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5760968PMC
August 2017

High genetic diversity among strains in Tehran, Iran.

J Clin Tuberc Other Mycobact Dis 2018 May 31;11:1-6. Epub 2018 Jan 31.

Infectious Diseases and Tropical Medicine Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.

Introduction: Tuberculosis (TB) still remains an important public health problem in Iran. The genotyping of isolates is expected to lead to a better understanding of transmission in Tehran, the most populated city of Iran.

Materials And Methods: A total of 2300 clinical specimens were obtained from TB suspected patients who were referred to a TB center in Tehran from Jan 2014 to Dec 2016. Identification was performed using both conventional and molecular methods. The presence of resistance to rifampicin was examined by the GeneXpert MTB/RIF. The standard 15-locus mycobacterial interspersed repetitive units-variable number of tandem repeats (MIRU-VNTR) typing method was applied to genotype of clinical isolates.

Results: Of 2300 specimens, 80 isolates were identified as by using biochemical and molecular tests. Of 80 isolates, 76 (95%) had unique genotypic profiles and 4 (5%) shared a profile with one or more other strains. Based on single loci variation (SLV) 4 clonal complexes were observed. NEW-1 was found to be the most predominant lineage (22.5%) followed by West African (1.25%), Central Asian (CAS)/Delhi (1.25%), Bovis (1.25%), H37Rv (1.25%) and multiple matches (1.25%). Loci MIRU10, MIRU26, MTUB21 and QUB26 were found as highly discriminative. No mutation was detected in the hotspot region of rifampicin by using GeneXpert MTB/RIF.

Conclusions: Our study findings show that there was considerable genotypic diversity among isolates in Tehran. The 15-locus MIRU-VNTR showed high HGDI and could be used as a first-line genotyping method for epidemiological studies.
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http://dx.doi.org/10.1016/j.jctube.2018.01.001DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6830142PMC
May 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

Incidence of Ventilator-Associated Pneumonia in Critically Ill Children Undergoing Mechanical Ventilation in Pediatric Intensive Care Unit.

Children (Basel) 2017 Jul 3;4(7). Epub 2017 Jul 3.

BS of Nursery, Head Nurse of Pediatric Intensive Care Unit, Mofid children's hospital, Shahid Beheshti University of Medical Sciences, Tehran 1551415468, Iran.

Background: Among hospital-acquired infections (HAIs) in children, ventilator-associated pneumonia (VAP) is the most common after blood stream infection (BSI). VAP can prolong length of ventilation and hospitalization, increase mortality rate, and directly change a patient's outcome in Pediatric Intensive Care Units (PICU).

Objectives: The research on VAP in children is limited, especially in Iran; therefore, the identification of VAP incidence and mortality rate will be important for both clinical and epidemiological implications.

Materials And Methods: Mechanically ventilated pediatric patients were assessed for development of VAP during hospital course on the basis of clinical, laboratory and imaging criteria. We matched VAP group with control group for assessment of VAP related mortality in the critically ill ventilated children.

Results: VAP developed in 22.9% of critically ill children undergoing mechanical ventilation. Early VAP and late VAP were found in 19.3% and 8.4% of VAP cases, respectively. Among the known VAP risk factors that were investigated, immunodeficiency was significantly greater in the VAP group (p = 0.014). No significant differences were found between the two groups regarding use of corticosteroids, antibiotics, PH (potential of hydrogen) modifying agents (such as ranitidine or pantoprazole), presence of nasogastric tube and total or partial parenteral nutrition administration. A substantial number of patients in the VAP group had more than four risk factors for development of VAP, compared to those without VAP (p = 0.087). Mortality rate was not statistically different between the VAP and control groups (p = 0.477).

Conclusion: VAP is still one of the major causes of mortality in PICUs. It is found that altered immune status is a significant risk factor for acquiring VAP. Also, occurrence of VAP was high in the first week after admission in PICU.
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http://dx.doi.org/10.3390/children4070056DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5532548PMC
July 2017

Genotyping, antimicrobial resistance and virulence factor gene profiles of vancomycin resistance Enterococcus faecalis isolated from blood culture.

Microb Pathog 2017 Aug 31;109:300-304. Epub 2017 May 31.

Pediatric Infections Research Center, Mofid Children Hospital, Shahid Beheshti University of Medical Sciences, Tehran, 15468-15514, Iran. Electronic address:

Background: Enterococcus spp. is the common of intestinal micro flora in humans but nowadays this gram-positive bacterium causes the variety of nosocomial infections. Resistance to antibiotic and also, presence of different virulence genes in the enterococcus spp. can change it to problematic microorganisms in the health care centers. The aim of this study was determined the genotyping, antimicrobial resistance and virulence factor gene profiles of vancomycin resistance Enterococcus faecalis isolated from blood culture.

Methods: In this study, enterococcus isolated from BACTEC was collected and antibiotic susceptibility testing was done according to CLSI recommendation. Important virulence genes and vancomyci resistance genes were detected by PCR and molecular typing was performed by RAPD PCR assay.

Results: Nine enterococcus collected from 194 positive BACTEC and seven out of nine were vancomycin-resistant enterococcus (VRE). vanA gene observed in all VRE and none of strains carried vanB and vanC genes. efbaA and gelE virulence factors have been detected in all strains. ace, esp, and cyl virulence factors genes harbored in two, seven and eight isolates respectively. asaI was not detected in any strains. All seven VRE isolates were related to the one specific molecular type and two different molecular types observed in the two vancomycin susceptible enterococci according to molecular epidemiology results.

Conclusion: More prevalence of the VRE in enterococcus isolated from BACTEC is so important and on the other hand high genetic relationship in the isolated VRE can be very considerable for nosocomial infection committee in the hospital.
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http://dx.doi.org/10.1016/j.micpath.2017.05.039DOI Listing
August 2017

Diagnostic test accuracy of adenosine deaminase for tuberculous meningitis: A systematic review and meta-analysis.

J Infect 2017 06 31;74(6):545-554. Epub 2017 Mar 31.

School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran. Electronic address:

Introduction: The measurement of adenosine deaminase (ADA) level in cerebrospinal fluid (CSF) has generated as a suitable test for tuberculous meningitis (TBM) diagnosis. The main objective in the present meta-analysis focused on analyzing the ADA test accuracy in order to diagnose TBM.

Methods: We searched several databases including Medline, Embase and Cochrane databases to identify studies addressing the diagnosis of TBM. The quality of included reports were assessed by RevMan5 software (via QUADS2 checklist). Accuracy measures of ADA test (sensitivity, specificity and others) pooled with random effects models. In addition, the data was elicited by using midas and metan packages in stata (version 12).

Result: Twenty studies were eligible for inclusion within the meta-analysis. The pooled sensitivity and specificity for TBM diagnosis hallmarks were 89% (95% CI: 0.84-0.92) and 91% (95% CI: 0.87-0.93), respectively. The positive likelihood ratio was 9.4 (95% CI: 7-12.8), negative likelihood ratio was 0.12 (95% CI: 0.09-0.17), and diagnostic odds ratio was 77 (95% CI: 45-132). Indeed, the area under the summary receiver operating characteristic (SROC) was 0.96.

Conclusion: It was magnificently attained that ADA test had a relatively high accuracy for TBM diagnosis.
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http://dx.doi.org/10.1016/j.jinf.2017.02.012DOI Listing
June 2017