Publications by authors named "Hossein Goudarzi"

72 Publications

Anti-proliferative effects of cell wall, cytoplasmic extract of and nisin through down-regulation of on SW480 colorectal cancer cell line.

Iran J Microbiol 2020 Oct;12(5):424-430

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

Background And Objectives: Colorectal cancer is one of the most types of cancer. Researchers have shown that lactic acid bacteria have antitumor activity. The cell wall of , as the bacterial cytoplasmic extract and nisin can affect the proliferation of cancer cells. Since cyclin D1 plays an important role in the progression of the cell cycle, its regulation can also be a therapeutic approach. We investigated the antiproliferative effect of cell wall, cytoplasmic extract and nisin on SW480 cancer cell line and the expression level of cyclin D1 gene in treated cancer cells.

Materials And Methods: SW480 cell lines were treated with different concentrations of bacterial cell wall, cytoplasmic extract and nisin. MTT test was also performed. The expression level of cyclin D1 gene was determined using Real time PCR. Data were analyzed using Graph Pad Prism software.

Results: The growth rate of cancer cells treated with nisin has significantly decreased compared to the cancer cells treated by other two substances (p< 0.05). Survival rates of the cancer cells treated by nisin at a concentration of 2000 μg, cytoplasmic extract, and cell wall were 34%, 47% and 49%, respectively. Real-time PCR results showed that cyclin D1 mRNA expression has significantly decreased in nisin treated sw480 cells (P<0.05).

Conclusion: The results of this study show that nisin, bacterial cytoplasmic extract, and bacterial cell wall have antiproliferative effects, which are associated with the decreased expression of cyclin D1 in SW480 cell line.
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http://dx.doi.org/10.18502/ijm.v12i5.4603DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7867695PMC
October 2020

MicroRNAs in the interaction between host-bacterial pathogens: A new perspective.

J Cell Physiol 2021 Feb 18. Epub 2021 Feb 18.

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

Gene expression regulation plays a critical role in host-pathogen interactions, and RNAs function is essential in this process. miRNAs are small noncoding, endogenous RNA fragments that affect stability and/or translation of mRNAs, act as major posttranscriptional regulators of gene expression. miRNA is involved in regulating many biological or pathological processes through targeting specific mRNAs, including development, differentiation, apoptosis, cell cycle, cytoskeleton organization, and autophagy. Deregulated microRNA expression is associated with many types of diseases, including cancers, immune disturbances, and infection. miRNAs are a vital section of the host immune response to bacterial-made infection. Bacterial pathogens suppress host miRNA expression for their benefit, promoting survival, replication, and persistence. The role played through miRNAs in interaction with host-bacterial pathogen has been extensively studied in the past 10 years, and knowledge about these staggering molecules' function can clarify the complicated and ambiguous interactions of the host-bacterial pathogen. Here, we review how pathogens prevent the host miRNA expression. We briefly discuss emerging themes in this field, including their role as biomarkers in identifying bacterial infections, as part of the gut microbiota, on host miRNA expression.
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http://dx.doi.org/10.1002/jcp.30333DOI Listing
February 2021

Reduced Efflux Pumps Expression of with Essential Oil.

Iran J Med Sci 2020 Nov;45(6):463-468

Applied Microbiology Research Center, Department of Microbiology, Systems Biology and Poisonings Institute, Baqiyatallah University of Medical Sciences, Tehran, Iran.

Background: Efflux pumps such as MexEF-OprN and mexXY-OprM play an important role in the resistance of () to antibiotics. The present study aimed to assess the reduced expression of efflux pump genes of with essential oil (SKEO).

Methods: The present cross-sectional study was conducted in 2016 at the Microbiology Laboratory of Baqiyatallah University of Medical Sciences, Tehran, Iran. The disk diffusion method was used for susceptibility testing of gentamicin and norfloxacin. Minimum inhibitory concentration (MIC) was determined for gentamicin and norfloxacin. The antibacterial efficacy of SKEO was defined by determining the MIC values using the microdilution method. , the synergistic interaction of SKEO combined with gentamicin or norfloxacin was examined via checkerboard assay and defined as a fractional inhibitory concentration index. The reverse transcription-polymerase chain reaction technique was used to measure changes in the expression of the efflux pump genes. The data were analyzed using SPSS software version 16.0, and P<0.05 was considered statistically significant.

Results: The MIC values of SKEO were in the range of 6 to 12 µg/mL. In the presence of sub-inhibitory concentrations (1.16 to 2 MIC) of SKEO, synergistic effects were revealed using the checkerboard method. The effect of norfloxacin and gentamicin increased up to 8-fold. The expression of and was reduced after treatment with SKEO.

Conclusion: SKEO reduced the expression of efflux pumps and the MIC values of norfloxacin and gentamicin in vitro.
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http://dx.doi.org/10.30476/ijms.2019.72675DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7707626PMC
November 2020

Protective effect of influenza vaccination on cardiovascular diseases: a systematic review and meta-analysis.

Sci Rep 2020 11 26;10(1):20656. Epub 2020 Nov 26.

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

Cardiovascular diseases (CVDs) are among the leading causes of mortality and morbidity worldwide. There are many contrasting ideas on the effectiveness of influenza vaccination on CVDs. This study aimed to investigate the association between influenza vaccination and the risk of CVDs. We systematically searched all PubMed/Medline, EMBASE, and the Cochrane library entries up to November 2019 for studies of influenza vs. the CVDs outcomes. We conducted a random-effects meta-analysis using the inverse variance method for pooled risk ratios (RR) or odds ratios (OR) and evaluated statistical heterogeneity using the I statistic. We identified 17 studies (6 randomized controlled trial [RCT], 5 cohorts, and 6 case-control) with a total of 180,043 cases and 276,898 control participants. The pooled RR of developing CVDs after influenza vaccination in RCT studies was 0.55 (95% CI 0.41-0.73), which was significant (P-value = 0.00). The pooled OR of decreasing CVDs after influenza vaccination in cohort studies was 0.89 (95% CI 0.77-1.04). The pooled OR of developing CVDs after influenza vaccination by pooling case-control studies was 0.70 (95% CI 0.57-0.86, (P-value = 0.00). All of these studies suggest decreased risks of CVDs with influenza vaccination. The current study does support the protective role of influenza vaccination on CVDs events. Health authorities may develop evidence-based preventive strategies to offer influenza vaccination in patients with CVDs.
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http://dx.doi.org/10.1038/s41598-020-77679-7DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7692477PMC
November 2020

Involvement of the AcrAB efflux pump in ciprofloxacin resistance in clinical Klebsiella pneumoniae isolates.

Infect Disord Drug Targets 2020 Sep 5. Epub 2020 Sep 5.

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

Background: Increasing prevalence of multiple antibiotic resistance in Klebsiella pneumoniae strains confines the therapeutic options used to treat bacterial infections.

Objective: We aimed in this study to investigate the role of AcrAB, qepA efflux pump, and AAC(6')-Ib-cr enzyme in ciprofloxacin resistance and to detect the RAPD-PCR fingerprint of K. pneumoniae isolates.

Methods: In total, 117 K. pneumoniae isolates were collected from hospitalized patients in three hospitals in Tehran, Iran from August 2013 to March 2014. Antimicrobial susceptibility tests were performed by the disk diffusion method. Molecular identification and expression level of encoding quinolone resistance genes, acrA, acrB, qepA, and aac(6')-Ib-cr, was performed by PCR and real-time PCR assays, respectively. All the K. pneumoniae isolates containing these genes was used simultaneously for RAPD-PCR typing.

Results: Colistin and carbapenems were the most efficient antibiotics against the clinical isolates of K. pneumoniae. PCR assay demonstrated that among the 117 isolates, 110 (94%) and 102 (87%) were positive for acrA and acrB gene, and for qepA and aac(6')-Ib-cr genes, 5 (4%) and 100 (85%) isolates were detected, respectively. Determination of AcrAB pump expression in 21% of strains demonstrated an increased expression, and the mean increase expression for acrB genes was 0.5-81. The results of RAPD-PCR reflected that in 95% CI, all isolates belong to a clone.

Conclusion: A high prevalence of genes encoding quinolone resistance in K. pneumoniae was detected in clinical samples. Therefore, control of infection and prevention of drug-resistant bacteria spread need careful management of medication and identification of resistant isolates.
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http://dx.doi.org/10.2174/1871526520999200905121220DOI Listing
September 2020

In silico analysis of a chimeric fusion protein as a new vaccine candidate against type A and alpha toxins.

Comp Clin Path 2020 Jul 14:1-9. Epub 2020 Jul 14.

Department of Anaerobic Bacterial Vaccines Production, Razi Vaccine and Serum Research Institute, Agricultural Research, Education and Extension Organization (AREEO), Karaj, Iran.

In silico analysis is the most important approach to understand protein structure and functions, and the most important problem for designing and producing a fusion construct is producing large amounts of functional protein. type A and produce alpha () and alpha toxins respectively. can cause gas gangrene and gastrointestinal diseases. can cause traumatic and non-traumatic gas gangrene. The aim of current research was in silico analysis of a chimeric fusion protein against type A and alpha toxins. Firstly, the chimeric fusion gene was designed according to nucleotide sequences of type A alpha (KY584046.1) and alpha (JN793989.2) toxin genes and then its fusion protein is constructed by amino acid sequences of type A and alpha toxins. Secondly, online software was used to determine prediction of secondary and tertiary structures and physicochemical characteristics of the fusion protein. Finally, the validation of the fusion protein was confirmed by Rampage and proSA program. The designed fusion protein has 777 amino acids in length. TASSER server and physicochemical parameters are showed: C-score = - 2.68 and molecular weight = 87.9 KD respectively. Rampage and proSA software revealed the fusion protein is valid. Deposited accession number for the sequence of the fusion gene in the GenBank is MK908396. The designed fusion protein is valid and functional. Thus, the fusion gene could be used for clone and expression in a proper prokaryotic cell and also as a recombinant vaccine candidate.
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http://dx.doi.org/10.1007/s00580-020-03136-6DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7358331PMC
July 2020

Drug susceptibility testing of Mycobacterium simiae: An emerging pathogen in Iran.

Infect Disord Drug Targets 2020 Jul 26. Epub 2020 Jul 26.

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

Introduction: Mycobacterium simiaeis an emerging pathogen in Iran and little is known about drug susceptibility patterns of this pathogen.

Materials And Methods: Twenty-five clinical isolates of M. simiaefrom 80 patients with confirmed NTM pulmonary disease were included in this study. For drug susceptibility testing (DST), proportional and broth microdilution methods were used according to the clinical and laboratory standards institute (CLSI) guideline.

Results: All clinical isolates of M. simiaewere resistant to isoniazid, rifampicin, ethambutol, streptomycin, amikacin, kanamycin, ciprofloxacin, and clarithromycin. They also were highly resistant to ofloxacin (80%). Susceptibility to ofloxacin was only noted in the 5 isolates.

Conclusions: Clinical isolates of M. simiae were multidrug-resistant, and had different drug susceptibility patterns than previously published studies. DST results can assist in selecting more appropriate treatment regimens. Newer drugs with proven clinical efficacy correlating with in vitrosusceptibility should be substituted with first-and second-line anti-TB drug testing.
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http://dx.doi.org/10.2174/1871526520999200727114148DOI Listing
July 2020

Genetic analysis of methicillin-susceptible Staphylococcus aureus clinical isolates: High prevalence of multidrug-resistant ST239 with strong biofilm-production ability.

J Clin Lab Anal 2020 Nov 21;34(11):e23494. Epub 2020 Jul 21.

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

Background: The distributions of methicillin-susceptible Staphylococcus aureus (MSSA) are divers geographically with different genetic backgrounds. Data related to molecular characteristics of MSSA compare to methicillin-resistant Staphylococcus aureus (MRSA) is sparse.

Methods: In this cross-sectional study, antimicrobial susceptibility testing, virulence genes analysis, biofilm formation, accessory gene regulator (agr) typing, and multilocus sequence typing (MLST) characterized on 75 MSSA isolates.

Results: Multidrug-resistance MSSA was found to be 84%. Forty-eight (64%) isolates were toxinogenic with 34 and 14 isolates carrying pvl and tst representing 45.3% and 18.7%. The most common SE genes were sed (20%), sec (16%), and sea (16%). Fifty-five (73.3%) isolates were confirmed as biofilm producer with a markedly high prevalence of fnbA (93.3%), fnbB (86.7%), icaA (65.3%), icaD (53.3%), can (24%), ebp (10.7%), and bap (1.3%). A total of 3 agr types (I, 73.3%; III, 16%; II, 10.7%) and 4 clonal complexes (CCs) and sequence types (STs), namely CC8/ST293 (45.3%), CC/ST22 (28%), CC/ST30 (16%), and CC/ST5 (10.7%) were detected in this study. All the high and low-level mupirocin resistance strains belonged to ST239 and ST22 strains, respectively. All the fusidic acid-resistant isolates carried fusC and belonged to ST30.

Conclusions: These findings indicated that ST239 with strong biofilm production ability is the most common type in MSSA strains isolated from patients. It seems that the antimicrobial resistance profiles, toxin, and biofilm formation were closely associated with specific STs. Further studies are required to identify and control of these clonal lineages in our area.
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http://dx.doi.org/10.1002/jcla.23494DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7676197PMC
November 2020

Genotype distribution of methicillin-susceptible Staphylococcus aureus clinical isolates in Iran: high multiresistant clonal complex 8.

BMC Res Notes 2020 Jun 8;13(1):277. Epub 2020 Jun 8.

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

Objective: Compared to methicillin-resistant Staphylococcus aureus (MRSA), there have been few studies focused on the molecular characterization of methicillin-susceptible Staphylococcus aureus (MSSA). In this cross-sectional study, 85 MSSA isolates were characterized by antimicrobial susceptibility testing, virulence genes analysis, accessory gene regulator (agr) typing, and S. aureus protein A locus (spa) typing.

Results: In present study, 9 different clonal complexes namely CC8-MSSA-t037 (22.4%), CC8-MSSA-t008 (11.8%), CC7-MSSA-t091 and CC30-MSSA-t021 (each 9.4%), CC8-MSSA-t037 (8.3%), CC398-MSSA-t034 (7.1%), CC22-MSSA-t005 (5.9%), CC5-MSSA-t002 and CC15-MSSA-t084 (each 4.7%), CC22-MSSA-t790 and CC59-MSSA-t437 (each 3.5%), CC22-MSSA-t1869, CC5-MSSA-t045, and CC45-MSSA-t015 (each 2.3%), CC30-MSSA-t318 and CC15-MSSA-t491 (each 1.2%) were found. agr types detected in tested strains were mainly type I (76.5%), II (12.9%), and III (10.6%). Of 85 MSSA examined isolates, 48 (56.5%) isolates were toxinogenic with 27 producing pvl (31.8%) and 21 tst (24.7%). The findings of the study show a high genetic diversity in MSSA strains warranting continued surveillance to provide critical insights into control and treatment of MSSA infections.
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http://dx.doi.org/10.1186/s13104-020-05127-wDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7282160PMC
June 2020

Determinants of medication adherence among hypertensive patients using the Pender's health promotion model.

J Educ Health Promot 2020 28;9:89. Epub 2020 Apr 28.

Social Determinants of Health Research Center, Hamadan University of Medical Sciences, Hamadan, Iran.

Background: Poor adherence in treatment and medication is a global issue in curing the chronic diseases such as hypertension. The present study was conducted to identify the factors related with medication adherence among hypertensive patients referred to the health centers of Borujerd based on the Pender's Health Promotion Model (HPM).

Materials And Methods: This cross-sectional study was conducted on 463 patients who were referred to the comprehensive health centers of Borujerd city by cluster sampling method in 2019. The data were collected using a questionnaire including demographic variables and Pender's HPM constructs. Data were analyzed by SPSS 18 software using Pearson correlation coefficient and linear regression.

Results: The mean and standard deviation of the participants' age was 63.29 ± 11.2 years. The results showed that hypertensive patients had a relatively desirable level of medication adherence behavior. Perceived barriers (β = -0.169), perceived self-efficacy (β = 0.196), activity related affect (β = 0.232), and following medication regimen (β = 0.225) were the best predictors of performing the medication adherence behavior. In total, different structures of the HPM explained 42.2% of the variation of medication adherence behavior changes.

Conclusions: According to the findings, the design of educational programs using HPM is recommended to increase the medication adherence among hypertensive patients.
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http://dx.doi.org/10.4103/jehp.jehp_687_19DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7271922PMC
April 2020

Prevalence, Genetic Diversity, and Temporary Shifts of Inducible Clindamycin Resistance Clones in Tehran, Iran: A Molecular-Epidemiological Analysis From 2013 to 2018.

Front Microbiol 2020 30;11:663. Epub 2020 Apr 30.

Department of Mycology, Pasteur Institute of Iran, Tehran, Iran.

The prevalence of as an aggressive pathogen resistant to multiple antibiotics causing nosocomial and community-acquired infections is increasing with limited therapeutic options. Macrolide-lincosamide streptogramin B (MLSB) family of antibiotics represents an important alternative therapy for staphylococcal infections. This study was conducted over a period of five years from August 2013 to July 2018 to investigate the prevalence and molecular epidemiology in Iran of inducible resistance in . In the current study, 126 inducible methicillin-resistant (MRSA) ( = 106) and methicillin-sensitive (MSSA) ( = 20) isolates were characterized by susceptibility analysis, resistance and virulence encoding gene distribution, phenotypic and genotypic analysis of biofilm formation, prophage typing, protein A locus () typing, staphylocoagulase (SC) typing, staphylococcal cassette chromosome (SCC) typing, and multilocus sequence typing. Of the 126 isolates, 76 (60.3%) were classified as hospital onset, and 50 (39.7%) were classified as community onset (CO). Biofilm formation was observed in 97 strains (77%). A total of 14 sequence types (STs), 26 types, 7 coagulase types, 9 prophage types, 3 types (no IV), and 9 clonal complexes (CCs) were identified in this study. The prevalence of the inducible MLSB (iMLSB) increased from 7.5% (25/335) to 21.7% (38/175) during the study period. The iMLSB MRSA isolates were distributed in nine CCs, whereas the MSSA isolates were less diverse, which mainly belonged to CC22 (7.95%) and CC30 (7.95%). High-level mupirocin-resistant strains belonged to ST85-SCC IV/t008 ( = 4), ST5-SCC IV/t002 ( = 4), ST239-SCC III/t631 ( = 2), and ST8-SCC IV/t064 ( = 2) clones, whereas low-level mupirocin-resistant strains belonged to ST15-SCC IV/t084 ( = 5), ST239-SCC III/t860 ( = 3), and ST22-SCCc IV/t790 ( = 3) clones. All the fusidic acid-resistant iMLSB isolates were MRSA and belonged to ST15-SCC IV/t084 ( = 2), ST239-SCC III/t030 ( = 2), ST1-SCC V/t6811 ( = 1), ST80-SCC IV/t044 ( = 1), and ST59-SCC IV/t437 ( = 1). The CC22 that was predominant in 2013-2014 (36% of the isolates) had almost disappeared in 2017-2018, being replaced by the CC8, which represented 39.5% of the 2017-2018 isolates. This is the first description of temporal shifts of iMLSB isolates in Iran that identifies predominant clones and treatment options for iMLSB -related infections.
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http://dx.doi.org/10.3389/fmicb.2020.00663DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7204094PMC
April 2020

Cyclin-dependent kinases and CDK inhibitors in virus-associated cancers.

Infect Agent Cancer 2020 1;15:27. Epub 2020 May 1.

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

The role of several risk factors, such as pollution, consumption of alcohol, age, sex and obesity in cancer progression is undeniable. Human malignancies are mainly characterized by deregulation of cyclin-dependent kinases (CDK) and cyclin inhibitor kinases (CIK) activities. Viruses express some onco-proteins which could interfere with CDK and CIKs function, and induce some signals to replicate their genome into host's cells. By reviewing some studies about the function of CDK and CIKs in cells infected with oncoviruses, such as HPV, HTLV, HERV, EBV, KSHV, HBV and HCV, we reviewed the mechanisms of different onco-proteins which could deregulate the cell cycle proteins.
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http://dx.doi.org/10.1186/s13027-020-00295-7DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7195796PMC
May 2020

Decreased carO gene expression and OXA-type carbapenemases among extensively drug-resistant Acinetobacter baumannii strains isolated from burn patients in Tehran, Iran.

Acta Microbiol Immunol Hung 2020 Apr 24. Epub 2020 Apr 24.

1Department of Microbiology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Islamic Republic of Iran.

A major challenge in the treatment of infections has been the rise of extensively drug resistance (XDR) and multidrug resistance (MDR) in Acinetobacter baumannii. The goals of this study were to determine the pattern of antimicrobial susceptibility, blaOXA and carO genes among burn-isolated A. baumannii strains. In this study, 100 A. baumannii strains were isolated from burn patients and their susceptibilities to different antibiotics were determined using disc diffusion testing and broth microdilution. Presence of carO gene and OXA-type carbapenemase genes was tested by PCR and sequencing. SDS-PAGE was done to survey CarO porin and the expression level of carO gene was evaluated by Real-Time PCR. A high rate of resistance to meropenem (98%), imipenem (98%) and doripenem (98%) was detected. All tested A. baumannii strains were susceptible to colistin. The results indicated that 84.9% were XDR and 97.9% of strains were MDR. In addition, all strains bore blaOXA-51 like and blaOXA-23 like and carO genes. Nonetheless, blaOXA-58 like and blaOXA-24 like genes were harbored by 0 percent and 76 percent of strains, respectively. The relative expression levels of the carO gene ranged from 0.06 to 35.01 fold lower than that of carbapenem-susceptible A. baumannii ATCC19606 and SDS - PAGE analysis of the outer membrane protein showed that all 100 isolates produced CarO. The results of current study revealed prevalence of blaOXA genes and changes in carO gene expression in carbapenem resistant A.baumannii.
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http://dx.doi.org/10.1556/030.2020.01138DOI Listing
April 2020

Prevalence and Mechanisms of Carbapenem Resistance in and : A Systematic Review and Meta-Analysis of Cross-Sectional Studies from Iran.

Microb Drug Resist 2020 Dec 28;26(12):1491-1502. Epub 2020 Apr 28.

Clinical TB and Epidemiology Research Center, National Research Institute of Tuberculosis and Lung Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran.

Carbapenem-resistant Enterobacteriaceae (CRE) represents an urgent threat worldwide. We aimed to investigate the frequency of carbapenem-resistant and in Iran. PubMed/Medline, Embase, Scopus, Web of Sciences, and Iranian databases were searched to find potentially relevant articles. Statistical analyses were performed using STATA version 14. Forty-nine studies fulfilled the inclusion criteria. The pooled rates of resistance to carbapenem in and were 24.0% (95% confidence interval [CI] 18.0-31.0) and 5.0% (95% CI 2.0-8.0), respectively. gene was the most common cause of carbapenem resistance in and CRE is prevalent in Iran, which confers the importance of strength prevention and control measures.
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http://dx.doi.org/10.1089/mdr.2019.0440DOI Listing
December 2020

Evaluating the expression level of miR-9-5p and miR-192-5p in gastrointestinal cancer: introducing novel screening biomarkers for patients.

BMC Res Notes 2020 Apr 19;13(1):226. Epub 2020 Apr 19.

Department of Microbiology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, 37517, Iran.

Objective: It has been indicated that there is a tight association between cancer and different factors, such as environment and genetics, including aberrantly expressed microRNAs. The crucial role of microRNAs in the regulation of diverse signaling pathways in gastrointestinal cancer has been established in several studies. In this study, we aimed to evaluate the expression of microRNA-9 and -192 in colon and gastric cancers. After extracting the RNA from tissues and serum samples of patients, suffering from colon and gastric cancer, cDNA was synthesized. Then by performing quantitative real-time PCR, we evaluated the expression level of miR-9-5p and miR-192-5p in collected samples.

Results: Unlike to colon cancer in which the expression level of miR-9-5p remained unchanged, the relative expression of this miRNA decreased remarkably in gastric cancer (with P value < 0.05), in comparison with normal adjacent tissues. In agreement with this finding, we also found that the expression level of miR-192-5p was decreased in gastric cancer tissues, compared to normal gastric tissue. Given the reduction in the expression level of miR-9-5p and miR-192-5p in gastric cancer, it could be postulated to consider these miRNAs as promising diagnostic biomarkers.
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http://dx.doi.org/10.1186/s13104-020-05071-9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7168809PMC
April 2020

Genetic diversity and biofilm formation analysis of Staphylococcus aureus causing urinary tract infections in Tehran, Iran.

J Infect Dev Ctries 2019 09 30;13(9):777-785. Epub 2019 Sep 30.

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

Introduction: Over the past decades, prevalence of biofilm-forming Staphylococcus aureus strains has significantly increased in urinary tract infections. The aim of this study was to investigate prevalence of biofilm forming and adhesion encoding genes and to analyze distribution of different agr and spa types in S. aureus isolates.

Methodology: In the present study, 75 S. aureus isolates obtained from patients with urinary tract infections were examined for susceptibility to antimicrobial agents. Adhesion, biofilm, and spa encoding genes were detected by PCR screening; agr types were determined using multiplex PCR.

Results: Among the 75 isolates, 72% were biofilm producers and 28% were non-biofilm producers. Notably, the ability to produce biofilm was higher among MRSA strains ompared to MSSA strains. The most prevalent biofilm forming gene was icaD (77.3%), followed by icaA (76%), icaB (57.3%) and icaC (50.7%). Adhesion genes clfA, clfB, fnbB, can, fnbA, ebp and bap were detected in 94.7%, 92%, 68%, 64%, 64%, 60% and 5.3% of the isolates, respectively. The spa types t426 and t7789 were found among the non-MDR isolates. It was found that t790, t084, t7789 and t325 spa types were biofilm producers, while t426 and t1339 spa types were non-biofilm producers.

Conclusion: Biofilm encoding genes icaD and spa type t790 and agr type III were the most prevalent factors among MDR biofilm producer isolates. The study emphasized that identification of genes and characterization of molecular types involved in biofilm formation should be considered.
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http://dx.doi.org/10.3855/jidc.11329DOI Listing
September 2019

Global estimate of phenotypic and genotypic ganciclovir resistance in cytomegalovirus infections among HIV and organ transplant patients; A systematic review and meta-analysis.

Microb Pathog 2020 Apr 29;141:104012. Epub 2020 Jan 29.

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

Human cytomegalovirus (CMV), an opportunistic pathogen belonging to Herpesviridae family, is considered as one of the major causes of morbidity and mortality among wide variety of patients, particularly in transplant recipients and HIV positive patients. As this virus can be resistant to treatment, frequency of CMV in patients who receive organ transplantation and people suffering from AIDS was studied between 1980 and 2019. Medline (via PubMed), Embase, Web of Science, and the Iranian Database were reviewed, and Comprehensive Meta-Analysis (V2.0, Biostat) software analyzed all data. Finally, we used Cochran's Q-statistic to encounter heterogeneity between different studies. Meta-analyses indicated, GCV resistance was 14.1% (95% CI 11.2-17.7); however, in patients suffering from AIDS and organ transplantation were 19.5% (95% CI 14.7-25.4) and 11.4% (95% CI 8.1-15.8), respectively. There were increasing rates in the prevalence of GCV resistance in CMV among transplant recipients, and HIV positive patients. Therefore, evaluation of these refractory infections is beneficial.
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http://dx.doi.org/10.1016/j.micpath.2020.104012DOI Listing
April 2020

E-cadherin, Snail, ZEB-1, DNMT1, DNMT3A and DNMT3B expression in normal and breast cancer tissues.

Acta Biochim Pol 2019 Dec;66(4):409-414

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

Objective: Breast cancer is known as one of very important cancers among females, given that a variety of external (i.e., environmental risk factors) and internal factors (i.e., genetics, and epigenetics) are related to the emergence and progression of breast cancer. Among genetic and epigenetic factors, DNA methyltransferase and EMT related genes have critical roles in breast cancer pathogenesis. In the study presented here, we investigated expression of DNA methyltransferases (e.g., DNMT1, DNMT3A and DNMT3B) and EMT related genes (e.g., E-cadherin, Snail, ZEB-1).

Methods And Materials: Tissue samples were collected from 18 cancer and 24 normal breast tissues. We evaluated the expression levels of DNA methyltransferases and EMT related genes using Quantitative real-time PCR (qRT-PCR).

Results: Our results indicated that the expression levels of ZEB-1, Snail, and DNMT3B were increased in breast cancer subjects in comparison to the control group. On the other hand, there was a significant decrease in E-cadherin expression in breast cancer tissues in comparison to the normal tissues. Moreover, there were no significant changes for DNMT1 and DNMT3A expression in breast cancer tissues when compared to the normal tissues.

Conclusion: Taken together, our finding show that up regulation of ZEB-1 and Snail could be associated with down regulation of E-cadherin and results in promotion of cancer cell invasion. Moreover, down regulation of E-cadherin may be related to deterioration of DNMT3B inpatients with breast cancer.
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http://dx.doi.org/10.18388/abp.2019_2808DOI Listing
December 2019

Afterglow Effects as a Tool to Screen Emissive Nongeminate Charge Recombination Processes in Organic Photovoltaic Composites.

ACS Appl Mater Interfaces 2020 Jan 6;12(2):2695-2707. Epub 2020 Jan 6.

KAUST Solar Center (KSC), Physical Sciences and Engineering Division (PSE) , King Abdullah University of Science and Technology (KAUST) , Thuwal 23955-6900 , Kingdom of Saudi Arabia.

Disentangling temporally overlapping charge carrier recombination events in organic bulk heterojunctions by optical spectroscopy is challenging. Here, a new methodology for employing delayed luminescence spectroscopy is presented. The proposed method is capable of distinguishing between recombination of spatially separated charge carriers and trap-assisted charge recombination simply by monitoring the delayed luminescence (afterglow) of bulk heterojunctions with a quasi time-integrated detection scheme. Applied on the model composite of the donor poly(6,12-dihydro-6,6,12,12-tetraoctyl-indeno[1,2-]fluorene--benzothiadiazole) (PIF8BT) polymer and the acceptor ethyl-propyl perylene diimide (PDI) derivative, that is, PIF8BT:PDI, the luminescence of charge-transfer (CT) states created by nongeminate charge recombination on the ns to μs timescale is observed. Fluence-dependent, quasi time-integrated detection of the CT luminescence monitors exclusively emissive charge recombination events, while rejecting the contribution of other early-time emissive processes. Trap-assisted and bimolecular charge recombination channels are identified based on their distinct dependence on fluence. The importance of the two recombination channels is correlated with the layer's order and electrical properties of the corresponding devices. Four different microstructures of the PIF8BT:PDI composite obtained by thermal annealing are investigated. Thermal annealing of PIF8BT:PDI shrinks the PDI domains in parallel with the growth of the PIF8BT domains in the blend. Common to all states studied, the delayed CT luminescence signal is dominated by trap-assisted recombination. Yet, the minor fraction of fully separated charge recombination in the overall CT emission increases as the difference in the size of the donor and acceptor domains in the PIF8BT:PDI blend becomes larger. Electric field-induced quenching measurements on complete PIF8BT:PDI devices confirm quantitatively the dominance of emissive trap-limited charge recombination and demonstrates that only 40% of the PIF8BT/PDI CT luminescence comes from the recombination of fully-separated charges, taking place within 200 ns after photoexcitation. The method is applicable to other nonfullerene acceptor blends beyond the system discussed here, if their CT state luminescence can be monitored.
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http://dx.doi.org/10.1021/acsami.9b16036DOI Listing
January 2020

Evaluation of microRNA-9 and -192 expression levels as biomarkers in patients suffering from breast cancer.

Biomed Rep 2020 Jan 21;12(1):30-34. Epub 2019 Nov 21.

Department of Microbiology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran 19839-63113, Iran.

Given the global outbreak of breast cancer and its debilitating effect on women's health, it is not surprising that tremendous efforts have been made with an aim of shedding more light on the mechanisms involved in the pathogenesis of this type of cancer. Among the long list of risk factors associated with this malignancy, recently, the role of microRNAs (miRNAs or miRs) has turned into a hotspot for breast cancer investigations. miRNAs approximately 20 nucleotides in length and are located in either an exon or an intron, playing a role in the regulation of gene expression. In the present study, we extracted RNA from both the serum and cancerous tissue of breast cancer patients and after synthesizing the cDNA, we performed quantitative PCR to determine the expression levels of miR-9 and miR-192. The resulting data revealed that while the mRNA expression level of miR-9 was significantly decreased in the breast cancer tissues, there was no noticeable change in the expression level of this miRNA in the serum samples. Likewise, we found that the marked downregulation of miR-192 was only restricted to the cancerous tissues, but was not found in the serum of patients. Based on the meaningful downregulation of the expression of miR-9 and miR-192, this study provides a plausible framework for these miRNAs as effective biomarkers for breast cancer patients.
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http://dx.doi.org/10.3892/br.2019.1257DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6906533PMC
January 2020

Evaluating the expression level of HERV-K env, np9, rec and gag in breast tissue.

Infect Agent Cancer 2019 29;14:42. Epub 2019 Nov 29.

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

Objective: Breast cancer is one of the most common health problems. It has been suggested that several risk factors, either considered as external or internal, play a critical role in the pathogenesis of breast cancer, which among them, HERV-k, has the most fundamental role. In the present study, we aimed to evaluate the role of HERV-k expressions in breast cancer progression.

Materials And Methods: We collected 40 breast cancer tissues and their normal adjacent ones. After extracting the RNA of breast samples, we evaluated the expression of HERV-k by using Quantitative real-time PCR (qRT-PCR).

Results: The resulting data revealed that while there was a meaningful increase in the expression level of HERV-k in breast cancer tissues ( ≤ 0.01, 0.05, 0.05, respectively), we failed to find any significant elevation in the expression level of mRNA level.

Conclusion: The results of our study suggested that there is a plausible correlation between the mRNA expression level of HERV-K and and the progression of breast cancer, proposing these markers as promising biomarkers to diagnose breast cancer.
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http://dx.doi.org/10.1186/s13027-019-0260-7DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6884765PMC
November 2019

Trends in multidrug-resistant tuberculosis in Tehran, Iran: an analysis of published data.

GMS Hyg Infect Control 2019 16;14:Doc11. Epub 2019 Aug 16.

Clinical TB and Epidemiology Research Center, National Research Institute of Tuberculosis and Lung Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran.

Multidrug-resistant tuberculosis (MDR-TB) is one of the major public health threats especially in developing countries. In Iran, the emergence and spread of MDR-TB are likely to pose a significant problem for the National Tubeculosis Control Program (NTP). In this study, to determine the trend of MDR-TB in Tehran, the results of published studies were analyzed. Several databases were searched, including Medline, Embase, Web of Science and Iranian databases. Studies which report the prevalence of MDR-TB by World Health Organization (WHO)-endorsed drug susceptibility testing (DST) methods were included in the study. Data were analyzed with SPSS 20 (SPSS, Chicago, Illinois, USA). Analysis of the MDR-TB trend did not show any increase among new TB cases, but the trend of MDR-TB was significantly increased among previously treated cases. The prevalence of MDR-TB from 48.0% in 1996 reached 58.0% in 2004 (P<0.05). Our analysis shows an increasing trend in MDR-TB, particularly in retreatment cases. This study strongly highlights the need to develop further strategies for surveillance, monitoring, and management of MDR-TB cases.
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http://dx.doi.org/10.3205/dgkh000327DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6734511PMC
August 2019

Inhibition of growth and gene expression in by anti- peptide nucleic acid.

Future Microbiol 2019 09;14:1123-1132

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

Multidrug-resistant isolates have become a serious concern in clinical microbiology. Antisense strategy, which specifically targets essential genes, could be helpful. cultures were treated with peptide conjugate-peptide nucleic acid (PPNA) specific for the gene. In addition, antimicrobial synergy with ciprofloxacin was tested. The results indicated anti--PPNA dramatically inhibited the growth of isolates in Mueller Hinton Broth with complete elimination of bacteria observed on cell cultures. Specifically, PPNA reduced the transcripts up to 50%. With antisense interference, growth inhibition was augmented through combination with ciprofloxacin. This study suggested that anti-gyrA-PPNAs could be introduced as a novel candidate for developing antisense antibiotic to treat all infections.
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http://dx.doi.org/10.2217/fmb-2019-0103DOI Listing
September 2019

Transcriptional Regulation of Epithelial to Mesenchymal Transition Related Genes by Lipopolysaccharide in Human Cervical Cancer Cell Line HeLa.

Asian Pac J Cancer Prev 2019 08 1;20(8):2455-2461. Epub 2019 Aug 1.

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

Objective: Cancer is one of the common diseases in the world, and cervical cancer is the fourth one. In this type of cancer, many risk factors, especially infectious diseases, such as human papilloma virus (HPV) and gram-negative bacteria can have important effects on the expression of epithelial to mesenchymal transition related genes like Snail, E-cadherin, and ZEB-1, responsible for connecting cell tissues. In this study, we have investigated the effect of Escherichia coli O111:B4 Lipopolysaccharide (LPS) on HPV positive cell line (HeLa), the expression level of the (Snail, E-cadherin, and ZEB-1), HPV oncogenes (E6, E7) and also microRNA-9, 192. Materials and Methods: HeLa cell line was treated with LPS to analyze Snail, E-cadherin, ZEB-1, E6, E7 and also microRNA-9, 192 expression by quantitative real-time PCR in 24, 48 and 72 hours. Results: Quantitative real-time PCR revealed a significant reduction in E-cadherin mRNA level at 10ug/L of LPS in three time-points and after 24 hours at 5ug/L of LPS; however, ZEB-1 at 10ug/L of LPS and Snail at 5, 10ug/L of LPS are up-regulated. E7 also illustrated a slight increase, but we did not find any relationship between E7 and LPS treatment. Additionally, there are upward trends in microRNA-9, 192 levels. Conclusion: The result of this study, LPS is able to reduce E-cadherin expression, caused by increase in repressor E-cadherin protein expression and some microRNAs, probably. Since bacterial infection can be in cervical site, it is likely to be effective in reducing the E-cadherin expression in the EMT and enhance cancer process, therefore; removing these infections by using the appropriate antibiotics may result in slowing down this process, which requires more research.
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http://dx.doi.org/10.31557/APJCP.2019.20.8.2455DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6852821PMC
August 2019

Aneuploidy and oncoviruses.

Rev Med Virol 2019 11 12;29(6):e2076. Epub 2019 Aug 12.

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

Seven oncogenic viruses are known for tumorigenesis and contribute to 12% of all human cancers. The oncogenic factors, the target tissue, and pathology of cancer vary among these viruses with several mechanisms proposed for the initiation and development of cancer. Aneuploidy in cells is associated with anomalies in chromosome number that can be a hallmark of cancer, a disease defined by expanded proliferative potential. In this review, we summarize the different mechanisms of aneuploidy and furthermore discuss recent findings of the role of viral oncoproteins in inducing cellular aneuploidy that might facilitate tumorigenesis. Improved understanding of viral oncogenesis may help to find new strategies for controlling virus-associated cancers.
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http://dx.doi.org/10.1002/rmv.2076DOI Listing
November 2019

Rapid detection and molecular survey of blaVIM, blaIMP and blaNDM genes among clinical isolates of Acinetobacter baumannii using new multiplex real-time PCR and melting curve analysis.

BMC Microbiol 2019 06 10;19(1):122. Epub 2019 Jun 10.

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

Background: Acinetobacter baumannii is a cosmopolitan bacterium that is frequently reported from hospitalized patients, especially those patients who admitted in the intensive care unit. Recently, multiplex real-time PCR has been introduced for rapid detection of the resistance genes in clinical isolates of bacteria. The current study aimed to develop and evaluate multiplex real-time PCR to detect common resistance genes among clinical isolates of A. baumannii.

Results: Multiplex real-time PCR based on melting curve analysis showed different T corresponding to the amplified fragment consisted of 83.5 °C, 93.3 °C and 89.3 °C for blaIMP, blaVIM and blaNDM, respectively. Results of multiplex real-time PCR showed that the prevalence of blaIMP, blaVIM and blaNDM among the clinical isolates of A. baumannii were 5/128(3.9%), 9/128(7.03%) and 0/128(0%), respectively. Multiplex real-time PCR was able to simultaneously identify the resistance genes, while showed 100% concordance with the results of conventional PCR.

Conclusions: The current study showed that blaVIM, was the most prevalent MBL gene among the clinical isolates of A. baumannii while no amplification of blaNDM was seen. Multiplex real-time PCR can be sensitive and reliable technique for rapid detection of resistance genes in clinical isolates.
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http://dx.doi.org/10.1186/s12866-019-1510-yDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6558830PMC
June 2019

Prevalence and Mechanisms of Carbapenem Resistance in : A Comprehensive Systematic Review of Cross-Sectional Studies from Iran.

Microb Drug Resist 2020 Mar 24;26(3):270-283. Epub 2019 May 24.

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

Carbapenem-resistant (CRAB) is recognized to be among the most difficult antimicrobial-resistant gram-negative bacilli to control and treat. An understanding of the epidemiology of CRAB and the mechanisms of resistance to carbapenems is necessary to develop strategies to curtail their spread. Electronic databases were searched from January 1995 to December 2017 for all studies, which: (1) provide data on the frequency and antibiotic resistance profile of the isolated and (2) describe the mechanisms of carbapenem resistance in detail. Sixty-eight studies were found referring to mechanisms of carbapenem resistance in clinical isolates of , and 56 studies were found referring to the frequency of CRAB. The pooled frequency of carbapenem resistance was 85.1% (95% confidence interval [CI]: 82.2-88.1) in 8,067 clinical isolates of . Resistances due to (55.3%), (41.4%), and (5.2%) genes were the most prevalent reported mechanisms of resistance to carbapenem, respectively. Our data warn that CRAB will rise if the current situation remains uncontrolled. Better control infection strategies and antibiotic managements, particularly in the health care systems, are needed to limit the spread of this pathogen.
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http://dx.doi.org/10.1089/mdr.2018.0435DOI Listing
March 2020

Latent tuberculosis infection in transplant candidates: a systematic review and meta-analysis on TST and IGRA.

Infection 2019 Jun 25;47(3):353-361. Epub 2019 Feb 25.

Clinical Epidemiology and Medical Statistics Unit, Department of Medical, Surgical and Experimental Sciences, University of Sassari, Sassari, Italy.

Introduction: The diagnostic accuracy of interferon-gamma release assays (IGRAs) and the tuberculin skin test (TST) for latent tuberculosis infection (LTBI) in transplant candidates is uncertain.

Methods: Pubmed, Embase and Cochrane library were searched to identify relevant studies. Quality of included studies was assessed with RevMan5 software (via GUADAS2 checklist). Accuracy measures of IGRAs and TST assays (sensitivity, specificity and others) were pooled with random effects model. Data were analyzed by STATA and Meta-DiSc.

Results: Twenty-eight studies were selected for full review, and 16 were included in the final analysis. The pooled sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), positive likelihood ratio (PLR), negative likelihood ratio (NLR) and diagnostic odds ratio (DOR) for TST were 46% [95% confidence interval (CI) 38-54%], 86% (95% CI 75-93%), 46.3% (95% CI 40-52), 88.7% (95% CI 87-89), 3.3 (95% CI 1.6-6.4), 0.63 (95% CI 0.52-0.77) and 5 (95% CI 2-12), respectively. For QFT-G, the pooled sensitivity, specificity, PPV, NPV, PLR, NLR, and DOR were 58% (95% CI 41-73%), 89% (95% CI 77-95%), 72.7% (95% CI 68-76), 80.6% (95% CI 78-82), 5.3 (95% CI 2.0-14.0), 0.47 (95% CI 0.30-0.75) and 11 (95% CI 3-46), respectively. Likewise, for T-SPOT.TB, the pooled sensitivity, specificity, PPV, NPV, PLR, NLR, and DOR were 55% (95% CI 40-70%), 92% (95% CI 87-95%), 60.4% (95% CI 47-72), 90.2% (95% CI 86-92), 6.7 (95% CI 4.0-11.1), 0.52 (95% CI 0.31-0.85) and 16 (95% CI 7-37), respectively.

Conclusions: IGRAs were more sensitive and specific than the TST with regard to the diagnosis of LTBI in the transplant candidates. They have added value and can be complementary to TST.
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http://dx.doi.org/10.1007/s15010-019-01285-7DOI Listing
June 2019

DNA methyltransferases in virus-associated cancers.

Rev Med Virol 2019 03 3;29(2):e2022. Epub 2018 Dec 3.

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

Human tumor viruses are either casually linked or contribute in the development of human cancers. Viruses can stimulate oncogenesis through affecting diverse biological pathways in human cells. Growing data have demonstrated frequent involvement of one of the most characteristic parts of cellular epigenetic machinery, DNA methylation, in the oncogenesis. DNA methylation of cellular genes is catalyzed by DNA methyltransferases (DNMTs) as a key effector enzyme in this process. Dysregulation of DNMTs can cause aberrant gene methylation in promoter of cancer-related genes including tumor suppressor genes, resulting in gene silencing. In this regard, the role of tumor viruses is remarkable. Here, in this review, we used published information to elucidate whether tumor viruses are able to manipulate DNMT regulation, and if so, what are its consequences in the process of oncogenesis. This essay also aims to shed light on which cellular pathways have been engaged by viruses to induce DNMTs.
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http://dx.doi.org/10.1002/rmv.2022DOI Listing
March 2019

Genetic features of Pseudomonas aeruginosa isolates associated with eye infections referred to Farabi Hospital, Tehran, Iran.

Int Ophthalmol 2019 Jul 7;39(7):1581-1587. Epub 2018 Jul 7.

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

Background: Pseudomonas is the most common cause of microbial keratitis especially in people who use contact lens. The virulence of Pseudomonas aeruginosa in different eye infections is associated with different virulence factors .

Methods: In this study, 54 P. aeruginosa isolates including 39 isolates from keratitis and 15 isolates from conjunctivitis were evaluated for their ability to form biofilm, production of protease, elastase, alkaline protease and their antibiotic-resistant patterns. The distribution of the exoS and exoU genes in the test strains were determined using PCR assays.

Results: Most of the eye infections (90.74%) were seen in people who used contact lenses, and in most of patients (72.22%), the infection was presented as keratitis. None of the isolates were resistant to a single antibiotic as tested. Multidrug resistance (MDR) was detected in two isolates (3.5%) which were resistant to more than one category of antibiotics. The exoU/exoS isolates were in majority although in total, compared to exoS, there were more exoU in a greater number of samples. Most of the strains produce elastase but among all of ocular isolates, only 5.8% of the strains showed alkaline protease activity. Most of the ocular isolates were not capable of producing biofilm.

Conclusions: In our study, a high prevalence of virulence factors was observed in P. aeruginosa isolates from contact lens wearer with keratitis. As the P. aeruginosa isolates from different infection origins and different geographic region may have different virulence factors, having a better perception of these differences could help to improve development of clinical instructions for the control of keratitis.
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http://dx.doi.org/10.1007/s10792-018-0980-5DOI Listing
July 2019