فهرست مطالب

Jundishapur Journal of Microbiology
Volume:8 Issue: 2, Feb 2015

  • تاریخ انتشار: 1393/11/17
  • تعداد عناوین: 13
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  • Effects of Benzalkonium Chloride on Planktonic Growth and Biofilm Formation by Animal Bacterial Pathogens
    Azizollah Ebrahimi, Majid Hemati *, Ziba Shabanpour, Saeed Habibian Dehkordi, Shahab Bahadoran, Sharareh Lotfalian, Shahin Khubani Page 1
    Background
    Resistance toward quaternary ammonium compounds (QACs) is widespread among a diverse range of microorganisms and is facilitated by several mechanisms such as biofilm formation..
    Objectives
    In this study, the effects of benzalkonium chloride on planktonic growth and biofilm formation by some field isolates of animal bacterial pathogens were investigated..
    Materials And Methods
    Forty clinical isolates of Escherichia coli, Salmonella serotypes, Staphylococcus aureus and Streptococcus agalactiae (10 isolates of each) were examined for effects of benzalkonium chloride on biofilm formation and planktonic growth using microtiter plates. For all the examined strains in the presence of benzalkonium chloride, biofilm development and planktonic growth were affected at the same concentrations of disinfectant..
    Results
    The means of strains growth increase after the minimal inhibitory concentration (MIC) were significant in all the bacteria (except for E. coli in 1/32 and S. agalactiae in of 1/8 MIC). Biofilm formation increased with decrease of antiseptics concentration; a significant increase was found in all the samples. The most turbidity related to S. aureus and the least to Salmonella..
    Conclusions
    Bacterial resistance against quaternary ammonium compounds is increasing which can increase the bacterial biofilm formation..
    Keywords: Biofilms, Benzalkonium chloride, Salmonella, Staphylococcus, Streptococcus
  • Roya Feyznezhad, Mohammad Amin Behzadi, Ramin Yaghobi, Mazyar Ziyaeyan * Page 2
    Background
    Hepatitis C virus (HCV) infection still exists as a health concern among the transplant patients. Because of the severity of the disease, different responses to treatment, and side effects resulting from long therapeutic period, determination of genotypes and viral loads can help choose the best treatment protocols..
    Objectives
    This study aimed to determine the HCV genotypes and its distribution patterns among liver, kidney, and bone marrow recipient candidates across Iran, referred to Namazi Hospital, southern Iran..Patients and
    Methods
    A total of 101 individuals, including 44 (43.6%) liver, 55 (54.5%) kidney, and 2 (2%) bone marrow recipient candidates, with ages ranging between 5 and 74 years (Mean ±SD: 46.53 ± 13.73 y) participated in this study. From those, whole blood sample were collected and anti-HCV antibodies, RNA detection, and genotyping were performed on plasma using commercial chromatographic immunoassay, TaqMan one-step real-time polymerase chain reaction (RT-PCR), and genotyping RT-PCR kits, respectively. The frequencies of anti-HCV antibodies, RNA, various genotypes, and the viral load were compared with respect to gender, age, and transplant recipient groups..
    Results
    Of 101 individuals, 47 (46.5%) were positive for anti-HCV antibodies and 34 (33.7%) for RNA with a significant difference (P < 0.05). RNA copy number ranged from 4.6 × 103 to 3.11 × 107 copies/mL, median: 2.92 × 106 copies/mL, with no statistical differences in all groups. Analyses revealed no significant differences between the frequencies of anti-HCV antibodies or RNA in different groups. The frequencies of the genotypes 1 (50%) and 3 (35.3%) were higher than those of the genotypes 2 (2.9%), 4 (2.9%), and undetermined one (8.8%). Genotype 1 was significantly more prevalent in liver transplant recipients, those older than 40 years, and male cases (P < 0.05)..
    Conclusions
    Considering the high frequency of genotypes 1 and 3 among the studied groups, it is suggested that before and after transplantation programs be improved to manage and treat the disease efficiently, based on the standard protocols for such genotypes in the region. Accordingly, the occurrence of post-transplant complications due to immunosuppression among all the recipients as well as reinfection in HCV infected liver transplant patients can be diminished..
    Keywords: Hepatitis C Virus_Transplant Recipient_Iran
  • Sareh Zhand, Chiman Karami, Ahmad Hosseinzadeh Adli, Alijan Tabarraei, Behnaz Khodabakhshi, Abdolvahab Moradi * Page 3
    Background
    Hepatitis B virus (HBV) infection is an important health concern worldwide, with critical outcomes. Hepatitis B e antigen (HBeAg) negative chronic hepatitis B is frequently caused by a mutation (G1896A) in the hepatitis B virus (HBV) precore (PC) reading frame, which creates a stop codon, causing premature termination of the HBe protein..
    Objectives
    This study aimed to investigate the G1896A PC mutation and its effect on HBeAg detection in chronic HBV patients..Patients and
    Methods
    In this study, 120 chronic HBV patients neither vaccinated or who had benefited from immunoglobulin therapy, were recruited. The HBV-DNA was extracted from plasma and polymerase chain reaction (PCR) was performed. Positive PCR products were subjected to automated sequencing. The HBV serological markers [hepatitis B s antigen (HBsAg), HBeAg] were tested..
    Results
    One hundred out of 120 (83.3%) patients were HBeAg negative and 100% were HBsAg positive. The comparison of nucleotide sequences with the reference sequence (Accession number: AB033559) in HBeAg negative patients showed that there was a high rate of mutations in G1896A (93.18%)..
    Conclusions
    This study indicates that the rate of G1896A mutation at the PC region among HBeAg negative patients, in the Golestan province of Iran, was similar to the average rate encountered in other parts of Iran. The PC stop codon mutation was detected in 93.18% of HBeAg negative patients. Further studies with larger sample sizes are required to elucidate the exact role of these mutations in the clinical course of chronic HBV infection..
    Keywords: Hepatitis B_Chronic_Mutation_Hepatitis B e Antigens_Iran
  • Gulfem Ece *, Bayri Erac, Hasan Yurday Cetin, Cem Ece, Aysegul Baysak Page 4
    Background
    Acinetobacter baumannii is an opportunistic pathogen, related with nosocomial infections such as bacteremia, urinary tract infections, and ventilator-associated pneumonia. Multidrug resistant (MDR) A. baumannii strains are first line causes of infection, especially in patients hospitalized at intensive care units (ICUs). Infection with MDR A. baumannii strains has a longer duration at ICUs and hospitals. There are studies using molecular methods which can differentiate MDR A. baumannii strains at the clonal level. This helps controlling these resistant strains and prevents their epidemy..
    Objectives
    The aim of our study was to investigate the antimicrobial susceptibility and clonal relationship between the A. baumannii strains isolated from our ICU..
    Materials And Methods
    The identification and antimicrobial susceptibility of 33 A. baumannii strains were performed by automatized Vitek version 2.0. The clonal relationship among A. baumannii strains was analyzed using enterobacterial repetitive intergenic consensus (ERIC) polymerase chain reaction (PCR)..
    Results
    A total of 33 A. baumannii strains were included in this study. A. baumannii complex strains were classified into seven clusters based on the fingerprint results. Our results revealed that two main clusters were responsible for the prevalence of A. baumannii complex strains at the ICU..
    Conclusions
    MDR A. baumannii strains cause an increment in morbidity and mortality, particularly in ICUs. The use of molecular epidemiological methods can help us with the detection of the pathogen and preventing from spreading of these resistant strains..
    Keywords: Acinetobacter baumannii, Molecular Epidemiology, Enterobacterial Repetitive Intergenic Consensus Polymerase Chain Reaction
  • Rasool Jafari, Amir Hossein Maghsood, Marzieh Safari, Milad Latifi, Mohammad Fallah * Page 5
    Background
    Fecal antigen detection using the enzyme linked immunosorbent assay (ELISA) and oocyst detection using auramine phenol (AP) staining methods, are told to be more sensitive compared to other conventional methods, for diagnosis of cryptosporidiosis..
    Objectives
    The aim of the present study was to evaluate the antigen-detection capacity in the stool specimens using ELISA and oocyst detection by AP staining methods, for the diagnosis of human cryptosporidiosis..
    Materials And Methods
    A total of 228 fecal samples were collected from residents of rural areas of Hamadan, West of Iran. Each fecal sample was divided into two parts, one kept frozen at -20˚C for Ag-capture ELISA and the other in 10% formalin for the AP staining method. Cryptosporidium Ag-detection ELISA procedure was performed according to the manual of the manufacturer. The preserved samples concentrated using the formalin-ether concentration technique were stained with AP and then investigated under florescent microscopy..
    Results
    Eight (3.5%) and three (1.3%) out of 228 fecal samples were positive for Cryptosporidium infection by ELISA and AP staining methods, respectively. Cryptosporidium Ag-detection using ELISA showed an increased frequency of the infection, compared to the AP staining method (P = 0.062)..
    Conclusions
    For epidemiological studies and diagnostic purposes of the Cryptosporidium infection, especially in asymptomatic individuals, Ag-detection ELISA is an easy to perform and accurate method, compared to other conventional microscopic methods..
    Keywords: Cryptosporidium, Enzyme, Linked Immunosorbent Assay, Auramine phenol, Oocysts
  • Reza Taherkhani, Fatemeh Farshadpour, Manoochehr Makvandi *, Mojtaba Hamidifard, Mahdi Esmailizadeh, Bijan Ahmadi, Hamid Heidari Page 6
    Background
    The human cytomegalovirus (HCMV) is a common pathogen which usually remains asymptomatic in the healthy adults; however, it can cause a symptomatic disease in the immunocompromised patients. The risk of infection with HCMV increases in ulcerative colitis (UC) patients as a result of receiving immunosuppressive agents..
    Objectives
    This study aimed to determine the prevalence and the glycoprotein B genotypes of HCMV among the patients with HCMV disease superimposed on an UC flare that required hospitalization in Imam Khomeini Hospital in Ahvaz, Iran, during 2010- 2012..Patients and
    Methods
    In this case-control study, formalin-fixed paraffin-embedded intestinal tissue samples were taken from 98 patients with UC disease including 53 males and 45 females (mean age ± standard deviation, 38.95 ± 17.93) and 67 control patients with noninflammatory disease who were referred to Imam Khomeini Hospital during 2010-2012. Detection of HCMV genome in intestinal samples was carried out by seminested polymerase chain reaction. Glycoprotein B genotypes were determined by sequencing..
    Results
    Among 98 patients with UC, only 12 (12.2%) patients were positive for HCMV genome, while the HCMV genome was not detected in any of the controls. (P = 0.002). The distribution of HCMV gB genotypes in 12 CMV-positive UC patients was as follow: gB1, 11 (91.7%) and gB3, 1 (8.3%). The most prevalent genotype in CMV-positive UC patients was gB1..
    Conclusions
    In this study, high prevalence of 91.7% HCMV gB1 genotype was predominant among HCMV-positive UC patients, which suggests that there might be an association between HCMV gB genotype 1 and UC disease..
    Keywords: Human Cytomegalovirus, Ulcerative Colitis, gB, Genotypes, Nested PCR, Intestinal, Tissue
  • Zohreh Hojati, Behnam Zamanzad, Morteza Hashemzadeh, Razieh Molaie, Abolfazl Gholipour * Page 7
    Background
    Urinary tract infections (UTIs) are one of main health problems caused by many microorganisms, including uropathogenic Escherichia coli (UPEC). UPEC strains are the most frequent pathogens responsible for 85% and 50% of community and hospital acquired UTIs, respectively. UPEC strains have special virulence factors, including type 1 fimbriae, which can result in worsening of UTIs..
    Objectives
    This study was performed to detect type 1 fimbriae (the FimH gene) among UPEC strains by molecular method..
    Materials And Methods
    A total of 140 isolated E. coli strains from patients with UTI were identified using biochemical tests and then evaluated for the FimH gene by polymerase chain reaction (PCR) analysis..
    Results
    The UPEC isolates were identified using biochemical tests and were screened by PCR. The fimH gene was amplified using specific primers and showed a band about 164 bp. The FimH gene was found in 130 isolates (92.8%) of the UPEC strains. Of 130 isolates positive for the FimH gene, 62 (47.7%) and 68 (52.3%) belonged to hospitalized patients and outpatients, respectively..
    Conclusions
    The results of this study indicated that more than 90% of E. coli isolates harbored the FimH gene. The high binding ability of FimH could result in the increased pathogenicity of E. coli; thus, FimH could be used as a possible diagnostic marker and/or vaccine candidate..
    Keywords: Urinary Tract Infections, Uropathogenic Escherichia Coli, FimH
  • Saeide Saeidi, Negar Amini Boroujeni *, Hassan Ahmadi, Mehdi Hassanshahian Page 8
    Background
    The extended-spectrum beta-lactamase (ESBL) -producing Escherichia coli isolates make many serious infections, especially urinary tract infections..
    Objectives
    The purpose of this study was to determine the antibacterial activities of some natural plant extracts against ESBL-producing E. coli isolates, which harbor the TEM gene in urine samples of the patients who have urinary tract infections..
    Materials And Methods
    Evaluation has to be exactly determined for both methods of disk diffusion test and polymerase chain reaction (PCR), separately. We evaluated 120 strains of E. coli isolates from the urine culture of the patients in Boo-Ali Hospital (Zahedan, south-eastern Iran) who were suffering from urinary tract infections. The ESBL-producing E. coli isolates were evaluated by disk diffusion test and PCR through TEM gene detection. The minimal inhibitory concentration (MIC) of commonly used antibiotics including ceftazidime, ceftriaxon, amikacin, gentamicin and ciprofloxacin along with the MIC of the alcoholic extract of different natural plants including Myrtus communis L (Myrtaceae), Amaranthus retraflexus (Amaranthaceae), Cyminum cuminum L (Apiaceae), Marrubium vulgare (Laminaceae) and Peganum. harmala (Zygrophyllaceae) against the ESBL-producing E. coli isolates, which harbor the TEM genes, were determined using the microdulition method..
    Results
    Results of this study showed that in disk diffusion method, 80 samples of E. coli produced ESBLs. In PCR method, the TEM gene distribution in the isolated ESBL-producing organisms was 50 (41.6%). Amikacin was the most effective anti-bacterial agent and ciprofloxacin was the least effective against E. coli isolates. All the natural plant extracts mentioned above, especially P. harmala, were effective against the selected isolates of ESBL-producing E. coli. The most frequent ESBL rate producing E. coli isolates (32 out of 50) had MIC of 2.5 mg/mL in ethanol extract of P. harmala..
    Conclusions
    The alcoholic extract of P. harmala was very effective against the selected ESBL-producing E. coli isolates harboring the TEM gene. Therefore, it could be suggested as an antibacterial agent in the future. More researches are necessary for detecting the mechanism of this plant’s behavior and its pharmacological effects..
    Keywords: Escherichia coli, Plant Extract, Urinary Tract
  • Maryam Fatemeh Sheikholeslami, Javid Sadraei *, Parissa Farnia, Mehdi Forozandeh Moghadam, Hamid Emadi Kochak Page 9
    Background
    Based on the authors’ knowledge, there is no study on the co-infection of opportunistic agents such as Mycobacterium tuberculosis and Pneumocystis jirovecii in the lungs of Iranian patients with immunosuppression..
    Objectives
    The current study aimed to show the rate of co-infection of M. tuberculosis and P. jirovecii in patients with Human Immunodeficiency Virus (HIV)..Patients and
    Methods
    Forty-five pulmonary samples were collected from 30 patients with HIV who also infected with Tuberculosis and Pneumonia. All of the patients were admitted to two university hospitals of Mycobacteriology and the Iranian HIV/AIDS research centers. DNA of P. jirovecii was detected using nested-Polymerase Chain Reaction (nested-PCR) assay..
    Results
    All of the patients were male with the mean age of 32.95 ± 7.15 years. The mean of CD4 cell count was 109.25 cell/mm3. Of 30 patients with HIV, three (10%) were co-infected with M. tuberculosis and P. jirovecii. No other causes of pneumonia were found in those three patients and CD4 cell counts less than 50 cell/mm3 was reported..
    Conclusions
    The results of the current study showed a high rate of co-infection of M. tuberculosis and P. jirovecii in the Iranian patients with HIV. As the immune system condition worsened, the probability of occurrence of Pneumocystis Pneumonia (PCP) increased. Therefore, more specific, most rapid and sensitive tests should be utilized for diagnosis of PCP in this group of patients..
    Keywords: Mycobacterium tuberculosis, Pneumocystis jirovecii, HIV, Co, infection
  • Hamid Sadeghian, Naiemeh Varasteh, Abbas Esmaeelzadeh, Hosein Nomani, Maliheh Alimardani, Mahdieh Davoodnejad, Mojtaba Meshkat, Mitra Ahadi, Samaneh Sepahi, Sina Rostami, Zahra Meshkat * Page 10
    Background
    Hepatitis delta virus (HDV) is dependent on the hepatitis B virus for transmission and propagation. Based on isolated HDV sequences from different parts of the world, at least three major different genotypes with different geographic distributions are suggested. Studies have shown that genotype 1 is the predominant genotype of HDV in different parts of Iran; however, the genotype distribution of this virus has not been identified in Mashhad, northeast Iran..
    Objectives
    This current study determines the frequency of HDV major genotypes in Mashhad, Iran..Patients and
    Methods
    Twenty-five participants were enrolled in this study. All samples were positive for HBsAg (determined by Enzyme-linked immunosorbent assay (ELISA)) and anti-HDV. RNA extraction and cDNA synthesis was performed. Then, PCR was performed and HDV genotypes were determined by restriction fragment length polymorphism (RFLP)..
    Results
    Of 25 patients, 12 (48%) were positive for HDV RNA. Genotype analysis of HDV RNA revealed that the prevalence of HDV genotypes I and II was 83.3% (n = 10) and 16.7% (n = 2), respectively..
    Conclusions
    This study showed that the most prevalent genotype of HDV in Mashhad was genotype I. It was of interest that in contrast to other provinces of Iran, HDV genotype 2 was observed in Mashhad. Similar studies with larger sample sizes could provide valuable information regarding the molecular epidemiology and geographical distribution. It may also help control and prevent the spread of hepatitis D virus infections. In addition, the genotyping of HDV may predict the severity of the disease..
    Keywords: Hepatitis Delta Virus, Genotype, Polymerase Chain Reaction, Restriction Fragment Length Polymorphism
  • Foroogh Neamati, Farzaneh Firoozeh *, Mahmood Saffari, Mohammad Zibaei Page 11
    Background
    Urinary tract infection (UTI) is one of the most prevalent infectious diseases. Uropathogenic Escherichia coli (UPEC), as the most important cause of UTI, are associated with a number of virulence factors..
    Objectives
    The current study aimed to investigate the virulence associated determinants as well as their patterns of antibiotic resistance in UPEC isolated from hospitalized patients with UTI..
    Materials And Methods
    A total of 150 E. coli isolates were collected from patients with UTI from December 2012 to June 2013 in Kashan, Iran. Antimicrobial susceptibility screening of 12 antibiotics was determined using disk diffusion method. Polymerase Chain Reaction (PCR) assay was used to detect virulence-related genes in UPEC strains. The purified PCR products were sequenced..
    Results
    Of the total 150 UPEC isolates, 111 (74%) were multidrug-resistant. High resistance was observed against ampicillin (81.3%), nalidixic acid (71.3%), cotrimoxazole (64.7%) and ciprofloxacin (61.3%), respectively. Eighty-four out of the 150 isolates showed resistance against the extended spectrum cephalosporins. Totally, virulence genes were detected in 126 (84%) UPEC isolates. The PCR results identified the traT gene in (74%), PAIs markers in (61.3%) and the pap gene in (16.6%) of the isolates..
    Conclusions
    The traT gene and PAI markers were highly prevalent among UPEC strains isolated from patients in Kashan, Iran; therefore these determinants could be used as targets for prophylactic interventions. Also there was a high level of resistance against the antibiotics commonly used for urinary tract infection treatment. To reach better therapeutic outcomes, treatment regimens have to be modified..
    Keywords: Antimicrobial Resistance, Urinary Tract Infection, Uropathogenic Escherichia coli
  • Kamiar Zomorodian, Pooria Ghadiri, Mohammad Jamal Saharkhiz, Mohammad Reza Moein, Peiman Mehriar *, Farideh Bahrani, Tahereh Golzar, Keyvan Pakshir, Mohammad Mehdi Fani Page 12
    Background
    Over the past two decades, there has been a growing trend in using oral hygienic products originating from natural resources such as essential oils (EOs) and plant extracts. Seven aromatic plants used in this study are among popular traditional Iranian medicinal plants with potential application in modern medicine as anti-oral infectious diseases..
    Objectives
    This study was conducted to determine the chemical composition and antimicrobial activities of essential oils from seven medicinal plants against pathogens causing oral infections..
    Materials And Methods
    The chemical compositions of EOs distilled from seven plants were analyzed by gas chromatography/mass spectrometry (GC/MS). These plants included Satureja khuzestanica, S. bachtiarica, Ocimum sanctum, Artemisia sieberi, Zataria multiflora, Carum copticum and Oliveria decumbens. The antimicrobial activity of the essential oils was evaluated by broth micro-dilution in 96 well plates as recommended by the Clinical and Laboratory Standards Institute (CLSI) methods..
    Results
    The tested EOs inhibited the growth of examined oral pathogens at concentrations of 0.015-16 µL/mL. Among the examined oral pathogens, Enterococcus faecalis had the highest Minimum Inhibitory Concentrations (MICs) and Minimum Microbicidal Concentrations (MMCs). Of the examined EOs, S. khuzestanica, Z. multiflora and S. bachtiarica, showed the highest antimicrobial activities, respectively, while Artemisia sieberi exhibited the lowest antimicrobial activity..
    Conclusions
    The excellent antimicrobial activities of the tested EOs might be due to their major phenolic or alcoholic monoterpenes with known antimicrobial activities. Hence, these EOs can be possibly used as an antimicrobial agent in treatment and control of oral pathogens..
    Keywords: Essential Oil, infections, Medicinal Plants
  • Asiye Akbarian *, Mohammad Hassan Shahhosseiny, Somayeh Vafaei, Elham Moslemi, Maryam Ghahri Page 13
    Background
    PCR is a molecular technique for herpes simplex virus (HSV) detection that can cause life-threatening infections such as encephalitis and keratitis. However, the main issues, false-negative results causing by PCR inhibitors, of this technique that reduce PCR efficiency. To overcome this problem, a competitive internal amplification control (IAC) was constructed for conventional PCR using the PCR-cloning technique..
    Objectives
    The purpose of this study is the design of competitive IAC for PCR diagnosis of HSV, which in fact is the main cause of keratitis and viral encephalitis in developed countries..
    Materials And Methods
    Composite primers for PCR amplification of Leishmania major kDNA (kinetoplast DNA) were designed and optimized to use as IAC-HSV. IAC-HSV amplified in a non-stringent condition, ligated into pTZ57R plasmid vector, and transformed into Escherichia coli JM207 and then cloned. Resulting IAC was used for 105 CSF and 78 keratitis specimens..
    Results
    PCR amplicons for HSV and IAC-HSV were 454-bp and 662-bp, respectively. Detection limit of IAC was determined as 1000 plasmids per PCR reaction. IAC sensitivity for HSV detection was determined as 1000 plasmids per PCR reaction. IAC sensitivity for HSV detection was 500 copies/mL of HSV DNA. Among all specimens, 7 inhibited specimens were detected..
    Conclusions
    Indeed, using other DNA as an IAC is expected to detect false-negative results and amplification of the DNA is the key tool to examine the accuracy of amplification and detection steps. This internal amplification control is applicable for early reliable diagnosis of HSV in different loads of virus in different specimens..
    Keywords: Herpes Simplex Virus, PCR, Leishmania Major, pTZ57R