Tehran University of Medical Sciences Journal of Medical Bacteriology 2251-8649 4 3-4 2015 09 01 56 60 EN Zahra Ghareboghy Sarmad Department of Microbiology, Faculty of Biological Sciences, Shahid Beheshti University, Tehran, Iran. Fereshteh Eftekhar Department of Microbiology, Faculty of Biological Sciences, Shahid Beheshti University, Tehran, Iran. 2016 09 13 2016 09 13 Background:   Acinetobacter baumannii has become one of the most important causes of nosocomial infections in recent years. The organism seems to be resistant to most classes of antibiotics. Carbapenems are considered the most effective drugs for treatment of these infections. However, increasing emergence of carbapenem resistant A. baumannii has become a major healthcare problem.   Methods:  The present study was conducted to compare the antibiotic susceptibility of 61 isolates of A. baumannii (31 from patients with burn infections and 30 from non-burn patients) to 12 antibiotics including imipenem and meropenem by disc diffusion.   Results:   Both groups of the isolates showed high levels of resistance to all classes of antibiotics except for aminoglycosides. Imipenem resistance was observed in 96.7% of the non-burn isolates and 100% among the burn strains.   Conclusion:   On the other hand, resistance to meropenem was significantly higher in non-burn isolates (83.3%) compared to the burn strains (6.4%). https://jmb.tums.ac.ir/index.php/jmb/article/view/210 https://jmb.tums.ac.ir/index.php/jmb/article/download/210/155

Tehran University of Medical Sciences Journal of Medical Bacteriology 2251-8649 4 3-4 2015 09 02 1 7 EN Hedroosha Molla Agha Mirzaeie Food Microbiology Research Center, Tehran University of Medical Sciences, Tehran, Iran. Ailar Sabbaghi Food Microbiology Research Center, Tehran University of Medical Sciences, Tehran, Iran. Mohammad Mehdi Soltan Dallal Division of Microbiology, Department of Pathobiology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran. 2016 09 13 2016 09 13 Background:  AmpC beta lactamases play a significant role in creating resistance to third generation cephalosporins worldwide. They mostly express on chromosome of Enterobacteriaceae especially Escherichia coli and cause consequential problem in clinical treatment and lead to failure in diagnosis and phenotypic test recommended by Clinical and Laboratory Standards Institute.   Methods: Totally 200 E. coli isolates from different hospitals of Tehran were collected. The isolates were screened by disk diffusion method according to the CLSI guidelines. The profiles and prevalence surveys of AmpC (Dha, CITM, Mox and FOX-type) β-lactamase genes in clinical isolates of E. coli by phenotypic and molecular methods.   Results:   Out of 200 E. coli isolated, 115 (89.8%) and 13 (10.2%) isolates were identified as ESBL- and AmpC- beta-lactamase producers, respectively. Among AmpC producers, 13 (100%) and 5 (38.5%) isolates was reported by PCR assay as blaCITM and Dha, respectively. Mox and FOX genes were not detected in any sample. Conclusion:   Our results highlight the importance of using molecular detection methods to identify β-lactamase-producer that have resistance to antibiotics. https://jmb.tums.ac.ir/index.php/jmb/article/view/203 https://jmb.tums.ac.ir/index.php/jmb/article/download/203/148

Tehran University of Medical Sciences Journal of Medical Bacteriology 2251-8649 4 3-4 2015 09 03 8 14 EN Aazam Haddadi Department of Biology, Karaj Branch, Islamic Azad University, Karaj, Iran. Seyedeh Mahsa Mirmostafa Department of Biology, Karaj Branch, Islamic Azad University, Karaj, Iran. Mahmoud Shavandi Microbiology and Biotechnology Group, Research Institute of Petroleum Industry, Tehran, Iran. 2016 09 13 2016 09 13 Background:    Unfortunately, antibiotic resistance has become an increasingly critical problem in many countries like Iran. Since there are very few published data on antibiotics resistance in Alborz province, the aim of this study was to survey the pattern of antimicrobial resistance and prevalence detection of TEM-type beta-lactamases among clinical isolates of Escherichia coli using universal primers.   Methods:    The study was performed on 83 clinical Escherichia coli strains collected from hospitals and clinical laboratories. Antimicrobial susceptibility was performed using Kirby-Bauer disk diffusion method against common antibiotics. Isolates were also screened for the production of extended spectrum beta-lactamases (ESBLs) by double disk synergy test (DDST). Positive isolates were evaluated by PCR analysis for the TEM family of ESBLs genes.   Results:   Isolates showed the highest resistance to amoxicillin (83%), whereas nitrofurantoin was the most effective drug, with only 8.4% resistance. The frequency of multi drug resistance (MDR) to more than 5 antibiotics was 79.5% (66 strains). ESBL screening of E. coli strains by DDST showed that out of 83 strains, 33 isolates were ESBL positive. Based on the PCR results 61 percent of phenotypic ESBL positive E. coli isolates possessed a single gene encoding a TEM type ESBL. Conclusion:   As the results of this study indicate, multidrug resistance is an increasing therapeutic concern and treatment requires further attention to the results of susceptibility tests. As antibiotic options in the treatment of ESBL-producing organisms are extremely limited, molecular screening by laboratories is suggested to reduce the risk of therapeutic defeat. https://jmb.tums.ac.ir/index.php/jmb/article/view/204 https://jmb.tums.ac.ir/index.php/jmb/article/download/204/149

Tehran University of Medical Sciences Journal of Medical Bacteriology 2251-8649 4 3-4 2015 09 01 15 23 EN Farzin Khorvash Isfahan University of Medical Sciences, Nosocomial Infection Research Center, Isfahan, Iran. Mohammad Reza Yazdani Isfahan University of Medical Sciences Infectious Diseases and Tropical Medicine Research Center, Isfahan, Iran. Shiva Shabani Isfahan University of Medical Sciences, Nosocomial Infection Research Center, Isfahan, Iran. Houri Alizadeh Islamic Azad University, Science and Research Branch, Shiraz, Iran. 2016 09 13 2016 09 13 Background:   Pseudomonas aeruginosa is a severe challenge for antimicrobial therapy, because of chromosomal mutations or exhibition of intrinsic resistance to various antimicrobial agents such as most β-lactams. We undertook this study to evaluate the existence of SME, AIM and VIM metallo-beta lactamases encoding genes among P. aeruginosa strains isolated from ICU patients in AL-Zahra Hospital in Isfahan, Iran.   Methods:  In a retrospective cross sectional study that was conducted between March 2012 to April 2013, in total 48 strains of P. aeruginosa were collected from clinical specimens of bedridden patients in ICU wards. Susceptibility test was performed by disc diffusion method. All of the meropenem resistant strains were subjected to modified Hodge test (MHT) for detection of carbapenemases. Multiplex PCR was performed for detection of VIM, blaAIM, blaSME genes.   Results:   In disk diffusion method imipenem and meropenem showed the most and colistin the least resistant antimicrobial agents against P. aeruginosa strains. Of the 48 isolates 36, (75%) were multidrug resistant. Amplification of β-lactamase genes showed the presence of blaVIM genes in 7 (%14.6) strains. All of the isolates were negative for blaSME and blaAIM genes. We couldn’t find any statistically significance difference among presence of this gene and MDR positive, age or source of the specimen.   Conclusion:   As patients with infections caused by MBL-producing bacteria are at an intensified risk of treatment failure, fast determination of these organisms is necessary. Our findings may provide useful insights in replace of the appropriate antibiotics and may also prevent MBLs mediated resistance problem. https://jmb.tums.ac.ir/index.php/jmb/article/view/205 https://jmb.tums.ac.ir/index.php/jmb/article/download/205/150

Tehran University of Medical Sciences Journal of Medical Bacteriology 2251-8649 4 3-4 2015 09 01 24 29 EN Mohammad Mehdi Soltan Dallal Department of Microbiology, Department of Pathobiology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran. AND Food Microbiology Research Center, Tehran University of Medical Sciences, Tehran, Iran Melisa Eghbal Food Microbiology Research Center, Tehran University of Medical Sciences, Tehran, Iran. AND Division of Microbiology, Department of Basic Sciences, Faculty of Science, Islamic Azad University of Qom, Qom, Iran. Azar Sharafianpour Food Microbiology Research Center, Tehran University of Medical Sciences, Tehran, Iran. Mohammad Reza Zolfaghari Division of Microbiology, Department of Basic Sciences, Faculty of Science, Islamic Azad University of Qom, Qom, Iran. Mohammad Kazem Sharifi Yazdi Department of Medical Laboratory Sciences, School of Paramedicine, Tehran University of Medical Sciences, Tehran, Iran. AND Zoonosis Research Center, Tehran University of Medical Sciences, Tehran, Iran. 2016 09 13 2016 09 13 Background:  Science the discovery of antibiotic, the incidence of antibiotic resistance has been inevitable. Although there has been many study in these area but problem still exists. The aim of this research was to study the serotyping and multiple antibiotic resistance patterns of Shigella sonnei isolated from diarrheal stool of children.   Methods:  The stool samples of children from zero to fourteen years of age admitted at Children Medical Center in Tehran were tested over period of twelvemonth. Identification of isolates was carried out according to standard methods and the antibiotic susceptibility test was performed using Kirby Bauer disk method.   Results:   Of the 200 samples analyzed 6 (3%) were tested positive for Shigella sonnei. The antibiotic resistance patterns showed that all were résistance to tetracycline, streptomycin, clindamycin and cortimoxazol, and 66.7% of the samples had multiples resistance to above antibiotics.   Conclusion:  The results showed that multiple antibiotics resistance of Shigella sonnei is increasing, therefore awareness about the prevention by improved hygiene and proper medication are needed to reduce the burden of the preventable infectious diseases among young children. https://jmb.tums.ac.ir/index.php/jmb/article/view/206 https://jmb.tums.ac.ir/index.php/jmb/article/download/206/151

Tehran University of Medical Sciences Journal of Medical Bacteriology 2251-8649 4 3-4 2015 09 04 30 34 EN Bahareh Lashtoo Aghaee Department of Pathobiology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran. Mohammad Hassan Shirazi Department of Pathobiology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran. Mohammad Reza Pourmand Department of Pathobiology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran. Mostafa Hosseini Department of Statistics School of Public Health, Tehran University of Medical Sciences, Tehran, Iran. Davood Afshar Department of Pathobiology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran. Sara Hajikhani Department of Pathobiology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran. Saeedeh Shobeiri Department of Immunology, Mazandaran University of Medical Sciences, Sari, Iran. 2016 09 13 2016 09 13 Background:  Vibrio species including V. cholera, V. mimicus, V. parahaemolyticus, and V. vulnificus may cause gastrointestinal diseases after seafood consumption, and wound infections in swimmers and fishermen after exposing to seawater. This study determined the prevalence of the four Vibrio species in Tonkabon and Ramsar recreational beach water (approximately 200 meter far from the place where the river reaches the sea) and estuaria (place where the river reaches the sea) in northern part of Iran from autumn 1391 through autumn 1392.   Methods:  Three hundreds water samples were collected for the detection of Vibrio species, using biochemical identification.   Results:   Genomic DNA extracted from isolates and 16Sr DNA PCR confirmed the successful isolation of 9 Vibrio species in recreational beach water region.   Conclusion:  Out of 300 samples, nine positive samples include one V. cholerae and eight V. parahaemolyticus were found at recreational beach (approximately 200 meter far from the place where the river reaches the sea). https://jmb.tums.ac.ir/index.php/jmb/article/view/207 https://jmb.tums.ac.ir/index.php/jmb/article/download/207/152

Tehran University of Medical Sciences Journal of Medical Bacteriology 2251-8649 4 3-4 2015 09 04 35 44 EN Yaser Sharifi Department of Microbiology, Qom Branch, Islamic Azad University, Qom, Iran. AND Department of Microbiology, Academic Center for Education, Culture and Research (ACECR), Qom Branch, Qom, Iran. AND Young Researchers and Elite Club, Qom Islamic Azad University, Qom, Iran. Abbas Morovvati Department of Microbiology, Qom Branch, Islamic Azad University, Qom, Iran. Azadeh Abedzadeh Department of Microbiology, Qom Branch, Islamic Azad University, Qom, Iran. Ali Javadi Department of Pathobiology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran. 2016 09 13 2016 09 13 Background:  Pathogenic bacteria because of beta-lactam antibiotic resistance genes are dangerous to society. This resistance due to ESBL genes, plasmids and transposons that by receiving or mutation occurs. The most important factor beta-lactam antibiotic resistance is beta lactamase enzymes. The purpose of this study was to evaluate the frequency of hospital opportunistic pathogenic bacteria producing ESBL and CTX-M genes identified are molecular methods.   Methods:  In this study, 500 isolates from patients in the ICU of ent antibiotics against this test strain. Reserpine significantly enhanced the antibacterial activities of kanamycin, nitrofurantoin, co-trimoxazole, erythromycin, ofloxacillin, gentamycin, rifampin, ciprofloxacin, nalidixic acid, minocycline, tobramycin, and amikacin against L. pneumophila which shows the resistances to these antibiotics are mediated by efflux system in this bacterium. https://jmb.tums.ac.ir/index.php/jmb/article/view/38 https://jmb.tums.ac.ir/index.php/jmb/article/download/38/33

Tehran University of Medical Sciences Journal of Medical Bacteriology 2251-8649 2 1-2 2015 10 12 41 53 EN Hashem Yaghoubi Department of Microbiology, Ardabil Branch, Islamic Azad University,Ardabil, IR Iran. Alireza Asef Department of Microbiology, Ardabil Branch, Islamic Azad University, Ardabil, IR Iran. Amirhosein Banki Department of Medical Sciences, Ardabil Branch, Islamic Azad University, Ardabil, IR Iran. 2015 10 12 2015 10 12 Background: Brevinin-2R, as 25 amino acids peptide of the skin of Rana ridibunda frog, possesses potent antimicrobial and low hemolytic activity. It has an N-terminal hydrophilic region and a C-terminal loop that is delineated by an intra-disulfide bridge. In our study, Brevinin-2R and its diastereomer as well  as its  cyclic  analogue  were  synthesized  and  characterized  in  order  to investigate its structural features and biological implications. Methods: MIC determination is based on the recommended classical method of national comittee for labratory safety standard (NCLSS) and standard by Hancock With some change on cationic peptides. In this study All bacterial strains were obtained from Industrial-Scientific Research center. Results: Both analogues showed lower antimicrobial activities compared to Brevinin-2R. In spite of Brevinin-2R peptide which shows low hemolytic activity, these analogues failed to show any hemolytic activity even at higher concentrations (up to 400 µ g/ml). Based on proteolytic stability measurements,diastereomer and cyclic analogues displayed 90% and 60% residual antimicrobial activity, respectively, while antimicrobial activity of Brevinin-2R was 20%. The CD analysis revealed that amphipathic α-helical conformation of the synthesized peptides is involved in antimicrobial effects. Conclusion: CD studies and HPLC based measurement of retention time using a reverse phase column indicated that the Brevinin-2R can form an amphipathic loop  resulting  in  an  enhanced  hydrophobicity.  The  hemolytic  activity  of Brevinin-2R and its analogues appeared to correlate with the retention time as well as the α-helicity. Accordingly, it seems that the combination of incorporating of D-amino acids into lytic peptides and their cyclization may result in developing new antimicrobial peptides with improved properties for treating infectious diseases.