Iranian Journal of Microbiology en-US (IJM Office) (TUMS Technical Support) Sun, 15 Jul 2018 22:11:19 +0430 OJS 60 Prevalence and antimicrobial resistance of shiga toxin-producing Escherichia coli and enteropathogenic Escherichia coli isolated from patients with acute diarrhea <p><strong>Background and Objectives:</strong> Diarrheal disease is still a major health problem in developing countries, where it is considered as one of the leading causes of morbidity and mortality especially in children. <em>Escherichia coli</em> is one of the important enteropathogenic bacteria which causes diarrhea in people. The aim of this study was to investigate the prevalence and antimicrobial resistance of shiga toxin–producing <em>E. coli</em> (STEC), Enterohaemorrhagic <em>E. coli</em> (EHEC), and Enteropathogenic<em> E. coli</em> (EPEC) in fecal samples collected from patients with acute diarrhea in a number of Iranian provinces.</p><p><br /><strong>Materials and Methods:</strong> A total of 102 strains of <em>E. coli</em> were isolated from fecal samples collected from patients with acute diarrhea using microbiological phenotypic tests. The antibiotic susceptibility pattern of all isolates was determined by the disk agar diffusion (DAD) method. The presence of <em>eae, bfp, stx1, sts2</em> and <em>EAF</em> genes in the isolates was investigated by PCR. The results were analyzed by SPSS; version 17.0 software.</p><p><br /><strong>Results:</strong> Out of 102 <em>E. coli</em> isolates screened for specific genes, 52 strains of <em>E. coli</em> were identified to harbor STEC 26 (50%), EPEC 13 (25%) and EHEC 13 (25%). Greatest resistance was observed to amoxicillin and ampicillin 40 (76.9%), and most sensitivity to imipenem 52 (100%) and gentamicin 40 (76.9%). We also found that 80.77% of diarrheic <em>E. coli</em> isolates were multidrug resistant (MDR).</p><p><br /><strong>Conclusion:</strong> The results showed that <em>E. coli</em> is one of the major causes of diarrhea and is highly resistant to commonly used antibiotics; therefore, officials must pay great attention to this issue in order to increase the health of the community.</p> Saeid Bouzari, Elham Farhang, Seyed Mostafa Hosseini, Mohammad Yousef Alikhani ##submission.copyrightStatement## Sun, 15 Jul 2018 22:11:14 +0430 High frequency of exfoliative toxin genes among Staphylococcus aureus isolated from clinical specimens in the north of Iran: Alarm for the health of individuals under risk <p><strong>Background and Objectives:</strong> Exfoliative toxins (ETs) of <em>Staphylococcus aureus</em> are the main reason of scalded skin syndrome in infants and young children. The aim of this study was to investigate the prevalence of<em> eta, etb</em> and <em>etd</em> genes in <em>S. aureus.</em></p><p><br /><strong>Materials and Methods:</strong> A total of 150 <em>S. aureus</em> isolates were collected from clinical specimens during the years 2014 to 2016 in the north of Iran. After confirmation of the species using standard diagnostic procedures, polymerase chain reaction was used for detection of the<em> eta, etb</em> and <em>etd</em> genes among the isolates.</p><p><br /><strong>Results:</strong> Overall, 131 (87.3%) isolates were positive for at least one of the ET genes; 115 (76.7%), 25 (16.7%) and 81 (54%) of the isolates carried the<em> eta, etb</em> and <em>etd</em> genes, respectively. Although <em>eta</em> and<em> etd</em> genes were present in all types of clinical samples,<em> etb</em> was found only in the wound, synovial fluid, sputum and tracheal aspirate. Overall, 7 toxin genotypes were observed, among which the genotypes <em>eta-etd, eta</em> and<em> eta-etb-etd</em> predominated at rates of 35.3%, 26.7% and 9.3%, respectively.</p><p><br /><strong>Conclusion:</strong> Detection of the high rate of prevalence of ET genes in the current study is considered as a serious problem because it is likely to spread and transfer these genes between strains. Furthermore, these isolates circulating in the community, particularly from infants, old people and immunocompromised patients, are important health-wise.</p> Mojtaba Mohseni, Fariba Rafiei, Ezzat Allah Ghaemi ##submission.copyrightStatement## Sun, 15 Jul 2018 22:11:15 +0430 Group B Streptococci and Trichomonas vaginalis infections in pregnant women and those with spontaneous abortion at Sanandaj, Iran <p><strong>Background and Objectives:</strong> Group B Streptococcali (GBS) is an important factor in newborn deaths in developed and developing countries. <em>Trichomoniasis</em> is one of the most prevalent sexually transmitted diseases (STDs) in the world, which is caused by protozoan <em>Trichomonas vaginalis (T. vaginalis)</em>. The present study compares the frequency of GBS and <em>T. vaginalis</em> genital infections in pregnant women, women with spontaneous abortion, as well as its role in spontaneous abortion.</p><p><br /><strong>Materials and Methods:</strong> In this case-control study, 109 women were included with spontaneous abortion with gestational ages between 11-20 weeks and 109 pregnant women with gestational ages between 35-37 weeks in Sanandaj, Iran. DNA was extracted by endocervical swabs and subjected to PCR assays. The independent t-test was used; and for comparing other qualitative variables in each group, the Chi-Square Test was used.</p><p><br /><strong>Results:</strong> The age of the women ranged from 19-43 years (29.6 ± 5.9) and in the control group the age range was from 19-42 years (27.8 ± 4.87). The rate of prevalence of Group B Streptococcal infection in the control group was 3.6%; and in the patient group there were 7.2% with the rate of prevalence of <em>T. vaginalis</em> in both groups as zero.</p><p><br /><strong>Conclusion:</strong> The present study showed that there is no relationship between GBS infections (P-value = 0.235) and <em>T. vaginalis.</em></p> Amjad Ahmadi, Fariba Farhadifar, Masoome Rezaii, Farnaz Zandvakili, Fariba Seyedoshohadaei, Mozhdeh Zarei, Sholeh Shahgheibi, Rashid Ramazanzadeh, Daem Roshani ##submission.copyrightStatement## Sun, 15 Jul 2018 22:11:15 +0430 Antibacterial effects of microbial synthesized silver-copper nanoalloys on Escherichia coli, Burkholderia cepacia, Listeria monocytogenes and Brucella abortus <p><strong>Background and Objectives:</strong> Bacterial resistance is an emerging public health problem worldwide. Metallic nanoparticles and nanoalloys open a promising field due to their excellent antimicrobial effects. The aim of the present study was to investigate the antibacterial effects of Ag-Cu nanoalloys, which were biosynthesized by <em>Lactobacillus casei</em> ATCC 39392, on some of the important bacterial pathogens, including <em>Escherichia coli, Burkholderia cepacia, Listeria monocytogenes</em> and <em>Brucella abortus.</em></p><p><br /><strong>Materials and Methods:</strong> Ag-Cu nanoalloys were synthesized through the microbial reduction of AgNO3 and CuSO4 by<em> Lactobacillus casei</em> ATCC39392. Furthermore, they were characterized by Fourier-Transform Infrared Spectrometer (FTIR) and Field Emission Scanning Electron Microscopy (FESEM) analysis in order to investigate their chemical composition and morphological features, respectively. The minimum inhibitory and minimum bactericidal concentrations of Ag-Cu nanoalloys were determined against each strain. The bactericidal test was conducted on the surface of MHA supplemented with 1, 0.1, and 0.01 μg/µL of the synthesized nanoalloy. The antimicrobial effects of synthesized nanoalloy were compared with ciprofloxacin, ampicillin and ceftazidime as positive controls.</p><p><br /><strong>Results:</strong> Presence of different chemical functional groups, including N-H, C-H, C-N and C-O on the surface of Ag-Cu nanoalloys was recorded by FTIR. FESEM micrographs revealed uniformly distributed nanoparticles with spherical shape and size ranging from 50 to 100 nm. The synthesized Ag-Cu nanoalloys showed antibacterial activity against <em>L. monocytogenes</em> PTCC 1298, <em>E. coli</em> ATCC 25922 and <em>B. abortus</em> vaccine strain. However, no antibacterial effects were observed against <em>B. cepacia</em> ATCC 25416.</p><p><br /><strong>Conclusion:</strong> According to the findings of the present research, the microbially synthesized Ag-Cu nanoalloy demonstrated antibacterial effects on the majority of the bacteria studied even at 0.01 μg/µL. However, complementary investigations should be conducted into the safety of this nanoalloy for in vivo or systemic use.</p> Sheida Mohammadi, Nima Hosseini Jazani, Mehri Kouhkan, Leila Ashrafi Babaganjeh ##submission.copyrightStatement## Sun, 15 Jul 2018 22:11:16 +0430 PCR-DGGE analysis of fungal community in manufacturing process of a traditional Iranian cheese <p><strong>Background and Objectives:</strong> The microbial communities of traditional milk-based food are of great importance in its manufacturing process, especially when using raw milk with natural cultures. Liqvan (Lighvan or Levan) is a traditional Iranian buried cheese, which is made from raw ewe´s milk without a starter addition. The aim of this study was to explore the fungal active population during this cheese manufacturing process by comparing DNA and RNA based culture independent method Denaturing Gradient Gel Electrophoresis (DGGE).</p><p><br /><strong>Materials and Methods:</strong> Four samples of each milk, curd and ripened cheese were collected from Liqvan village located in East Azerbaijan province of Iran. Total DNA and RNA of each sample were extracted and PCR amplicons of D1 region of 26S rRNA gene was targeted for DGGE analysis. This method applied at both DNA and RNA levels in order to examine which taxonomic groups of fungi are active at each step of ripening.</p><p><br /><strong>Results:</strong> DGGE profiles of yeast amplicons showed different results between extracted DNA and RNA during ripening process. However, the main group that is present in all stages of ripening process belongs to the genus <em>Candida</em> although <em>Kluyveromyces, Pichia, Galactomyces, Saccharomyces</em> and <em>Cryptococcus</em> are most abundant fungi.</p><p><br /><strong>Conclusion:</strong> As no starter culture added to Liqvan cheese it seems fungal diversity are mainly rely on the indigenous microbiota of milk. Furthermore, the percentage of the dominant fungal genera from the total sequences differed among DNA and cDNA libraries.</p> Mohaddaseh Ramezani, Seyed Masoud Hosseini, Seyed Abolhassan Shahzadeh Fazeli, Mohammad Ali Amoozegar, Javad Fakhari ##submission.copyrightStatement## Sun, 15 Jul 2018 22:11:17 +0430 Tracking leading anti-Candida compounds in plant samples; Plumbago europaea <p><strong>Background and Objectives:</strong> Due to the importance of finding new and more effective antifungal and antibacterial compounds against invasive vaginitis strains, this study was conducted for fast screening of plant samples.</p><p><br /><strong>Materials and Methods:</strong> Thirty Iranian plant samples were successively extracted by n-hexane, ethyl acetate and methanol to obtain a total of 90 extracts. Each extract was prepared in six concentrations and evaluated for antifungal activity via a micro-broth dilution method. Further phytochemical study of the aerial parts of <em>Plumbago europaea</em>, as the most promising source of anti-<em>Candida</em> compounds (with minimum inhibitory concentration of about 7µg/ml), was carried out and antifungal activity in the ethyl acetate extract was tracked using a combination of HPLC time-based fractionation and Thin Layer Chromatography-Bioautography via a bioassay-guided fractionation procedure. The compounds in the active region of the chromatogram were purified by a combination of column chromatography and preparative TLC, and then structure elucidation was achieved by 1D and 2D NMR, mass spectrometry and UV spectra.</p><p><br /><strong>Results:</strong> Seven compounds were isolated and identified: (1) plumbagin, (2) isoplumbagin, (3) 5, 8-dihydroxy-2-methyl-[1, 4] naphthoquinone, (4) droserone, (5) 7-methyljuglone, (6) Isozeylanone, and (7) methylene-3, 3’-diplumbagin. Antimicrobial activity of the purified compounds were also evaluated against <em>C. albicans</em> (MIC values ranging from 2 to 2500 µM) and <em>Gardnerella vaginalis</em> (MIC values ranging from 20 to 2500 µM).</p><p><br /><strong>Conclusion:</strong> These naphthoquinone compounds could be surveyed for finding new and more effective anti-vaginitis agents via drug design approaches.</p> Marzieh Sobhani, Mahdi Abbas-Mohammadi, Samad Nejad Ebrahimi, Atousa Aliahmadi ##submission.copyrightStatement## Sun, 15 Jul 2018 22:11:17 +0430 Enteroviruses and Adenoviruses in stool specimens of paralytic children- can they be the cause of paralysis? <p><strong>Background and Objectives:</strong> Acute flaccid paralysis (AFP) is a complicated clinical syndrome with a wide range of potential etiologies. Several infectious agents including different virus families have been isolated from AFP cases. In most surveys, Non-polio Enteroviruses (NPEVs) have been detected as main infectious agents in AFP cases; however, there are also some reports about <em>Adenovirus</em> isolation in these patients. In this study, NPEVs and <em>Adenoviruses</em> in stool specimens of AFP cases with or without Residual Paralysis (RP) with negative results for poliovirus are investigated.</p><p><br /><strong>Materials and Methods:</strong> Nucleic acid extractions from 55 AFP cases were examined by nested PCR or semi-nested PCR with specific primers to identify NPEVs or <em>Adenoviruses</em>, respectively. VP1 (for<em> Enteroviruses</em>) and hexon (for <em>Adenoviruses</em>) gene amplification products were sequenced and compared with available sequences in the GenBank.</p><p><br /><strong>Results:</strong> From 55 fecal (37 RP+ and 18 RP-) specimens, 7 NPEVs (12.7%) (2 cases in RP+) and 7 <em>Adenoviruses</em> (12.7%) (4 cases in RP+) were identified. <em>Echovirus</em> types 3, 17 and 30, <em>Coxsackie</em> virus A8, and <em>Enterovirus</em> 80 were among NPEVs and <em>Adenoviruses</em> type 2 and 41 were also identified.</p><p><br /><strong>Conclusion:</strong> Our finding shows that NPEVs and <em>Adenoviruses</em> may be isolated from the acute flaccid paralyses but there is no association between the residual paralyses and virus detection.</p> Maryam Yousefi, Ahmad Nejati, Seyed Mohsen Zahraei, Sussan Mahmoudi, Najmeh Parhizgari, Seyed Mohammad Jazayeri Farsani, Mahmood Mahmoodi, Rakhshandeh Nategh, Shohreh Shahmahmoodi ##submission.copyrightStatement## Sun, 15 Jul 2018 22:11:18 +0430 Role of TNF α, IL-6 and CXCL10 in Dengue disease severity <p><strong>Background and Objectives:</strong> Dengue virus infections (Dengue) have become increasingly common in Pakistan and can result in case fatalities if not managed appropriately. Patients with Dengue virus infection may be asymptomatic or present with Dengue fever (DF), Dengue with warning signs (DWS) or severe Dengue (SD). Severity in Dengue is coincident with an exacerbated production of lymphocyte-induced cytokines and chemokines which are associated with plasma leakage. We investigated the association of circulating levels of cytokines such as Interleukin (IL)-6, tumor necrosis factor (TNF)-alpha and CXCL-10 in Dengue patients with differing severity of disease.</p><p><br /><strong>Materials and Methods:</strong> Dengue infection was confirmed by testing for human IgM to the Dengue virus. Dengue patients (n=58) and healthy controls (n=33) were recruited. Dengue patients were grouped into those with DF (n=39), DWS (n=15) and SD (n=4). Serum IL-6, TNFα and CXCL10 levels were tested by ELISA. The Mann Whitney U test was used for statistical analysis.</p><p><br /><strong>Results:</strong> Circulating levels of TNFα (p≤0.001) and CXCL10 (p≤0.001) levels were increased in Dengue patients as compared with controls. When patients were stratified for disease severity, it was observed that CXCL10 was increased in DWS as compared to DF (p=0.046). IL-6 levels were increased in patients with SD as compared to those with DWS (p=0.044). TNFα levels were not found to differ between different groups of Dengue patients.</p><p><br /><strong>Conclusion:</strong> Raised CXCL10 and TNFα levels were associated with increased clinical severity of Dengue infection and probably increased disease progression due to excessive inflammation and increased vascular changes in the <br />patients.</p><p> </p> Kiran Iqbal Masood, Bushra Jamil, Maryam Rahim, Muniba Islam, Muhammad Farhan, Zahra Hasan ##submission.copyrightStatement## Sun, 15 Jul 2018 22:11:19 +0430