فهرست مطالب

Jundishapur Journal of Microbiology
Volume:8 Issue: 5, May 2015

  • تاریخ انتشار: 1394/03/29
  • تعداد عناوین: 13
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  • Farahnaz Bineshian *, Mohammad Hossien Yadegari, Zohre Sharifi, Mohammadreza Akbari Eidgahi, Reza Nasr Page 1
    Background
    Systemic candidiasis is a major public health concern. In particular, in immunocompromised people, such as patients with neutropenia, patients with Acquired Immune Deficiency Syndrome (AIDS) and cancer who are undergoing antiballistic chemotherapy or bone marrow transplants, and people with diabetes. Since the clinical signs and symptoms are nonspecific, early diagnosis is often difficult. The 65-kDa mannoprotein (MP65) gene of Candida albicans is appropriate for detection and identification of systemic candidiasis. This gene encodes a putative b-glucanase mannoprotein of 65 kDa, which plays a major role in the host-fungus relationship, morphogenesis and pathogenicity..
    Objectives
    The current study aimed to identify different species of Candida (C. albicans, C. glabrata and C. parapsilosis) using the Polymerase Chain Reaction (PCR) technique and also to evaluate C. albicans MP65 gene expression in BALB/C mice..
    Materials And Methods
    All yeast isolates were identified on cornmeal agar supplemented with tween-80, germ tube formation in serum, and assimilation of carbon sources in the API 20 C AUX yeast identification system. Polymerase Chain Reaction was performed on all samples using species-specific primers for the MP65 65 kDa gene. After RNA extraction, cDNA synthesis was performed by the Maxime RT Pre Mix kit. Candida albicans MP65 gene expression was evaluated by quantitative Real-Time (q Real-Time) and Real-Time (RT) PCR techniques. The 2-ΔΔCT method was used to analyze relative changes in gene expression of MP65. For statistical analysis, nonparametric Wilcoxon test was applied using the SPSS version 16 software..
    Results
    Using biochemical methods, one hundred, six and one isolates of clinical samples were determined as C. albicans, C. glabrata and C. parapsilosis, respectively. Species-specific primers for PCR experiments were applied to clinical specimens, and in all cases a single expected band for C. albicans, C. glabrata and C. parapsilosis was obtained (475, 361 and 124 base pairs, respectively). All species isolated by culture methods (100% positivity) were evaluated with PCR using species-specific primers to identify Candida species. Relative expression of Mp65 genes increased significantly after C. albicans injection into the mice (P < 0.05)..
    Conclusions
    The results of the current study showed that the PCR method is reproducible for rapid identification of Candida species with specific primers. Mp65 gene expression of C. albicans after injection into the mice was 2.3 folds higher than before injection, with this difference being significant. These results indicated that increase of Mp65 gene expression might be an early stage of infection; however definitive conclusions require further studies..
    Keywords: Candida, Pathology, Molecular, Genes
  • Ahmad Siti Junaidah, Sudi Suhaini, Hasidah Mohd Sidek, Dayang Fredalina Basri, Noraziah Mohammad Zin * Page 2
    Background
    The potential of secondary metabolites extracted from Streptomyces sp. to treat bacterial infections including infections with Staphylococcus aureus is previously documented. The current study showed significant antimicrobial activities associated with endophytic Streptomyces sp. isolated from medicinal plants in Peninsular Malaysia..
    Objectives
    The current study aimed to determine anti-methicillin-resistant-Staphylococcus aureus (MRSA) activities of Streptomyces sp. isolates..
    Materials And Methods
    Disc diffusion and Minimum Inhibitory Concentration (MIC) assay were used to determine the antibacterial activity of Streptomyces sp. isolates. Optimization of fermentation parameters for the most potent anti-MRSA extract in terms of medium type, pH, aeration rate, and culture period was also carried out. Lastly, toxicity of the extract against Chang liver cells was determined employing the MTT, 2- (3, 5- diphenyltetrazol-2-ium-2-yl) -4, 5-dimethyl -1, 3 - thiazole; bromide assay..
    Results
    The results indicated Streptomyces sp. SUK 25 isolates showed the most potent anti-MRSA activity. Disc diffusion assay revealed that spread plate technique was more efficient in screening anti-MRSA activity compared to pour plate (P < 0.05). To determine anti–MRSA MIC of Streptomyces sp. SUK 25, Thronton media was used. Therefore, MIC was determined as 2.44 ± 0.01 µg/mL, and accordingly, the lowest MIC was 1.95 µg/mL based on a seven-day culture, pH7, and aeration rate of 140 rpm. The crude extract was not toxic against Chang liver cells (IC50 = 43.31 ± 1.24 µg/mL)..
    Conclusions
    The Streptomyces sp. SUK 25 culturing was optimized using Thronton media, at pH 7 and aeration of 140 rpm. Further isolation and identification of bioactive compounds will develop anti-MRSA therapeutics..
    Keywords: Streptomyces sp., MRSA, Culture
  • Nasser Keikha, Seyyed Amin Ayatollahi Mousavi *, Ali Reza Nakhaei, Mohammad Hossein Yadegari, Gholam Hossein Shahidi Bonjar, Somayyeh Amiri Page 3
    Background
    Human cutaneous infection caused by a homogeneous group of keratinophilic fungi called dermatophytes. These fungi are the most common infectious agents in humans that are free of any population and geographic area. Microsporum canis is a cause of dermatophytosis (Tinea) in recent years in Iran and atypical strain has been isolated in Iran. Its cases occur sporadically due to M. canis transmission from puppies and cats to humans. Since this pathogenic dermatophyte is eukaryotes, chemical treatment with antifungal drugs may also affect host tissue cells..
    Objectives
    The aim of the current study was to find a new antifungal agent of soil-Actinomycetes from Kerman province against M. canis and Actinomycete isolates were identified by PCR..
    Materials And Methods
    A number of hundred Actinomycete isolated strains were evaluated from soil of Kerman province, for their antagonistic activity against the M. canis. M. canis of the Persian Type Culture Collection (PTCC) was obtained from the Iranian Research Organization for Science and Technology (IROST). Electron microscope studies of these isolates were performed based on the physiological properties of these antagonists including lipase, amylase, protease and chitinase activities according to the relevant protocols and were identified using gene 16SrDNA..
    Results
    In this study the most antagonist of Actinomycete isolates with antifungal activity against M. canis isolates of L1, D5, Ks1m, Km2, Kn1, Ks8 and Ks1 were shown in vitro. Electron microscopic studies showed that some fungal strains form spores, mycelia and spore chain. Nucleotide analysis showed that Ks8 had maximum homology (98%) to Streptomyces zaomyceticus strain xsd08149 and L1 displayed 100% homology to Streptomyces sp. HVG6 using 16SrDNA studies..
    Conclusions
    Our findings showed that Streptomyces has antifungal effects against M. canis..
    Keywords: Actinomycetes, Microsporum canis, Antifungal, 16SrDNA
  • Guoliang Li, Xudong Ma, Lisha Deng, Xixi Zhao, Yuejiao Wei, Zhongyang Gao, Jing Jia, Jiru Xu *, Chaofeng Sun Page 4
    Background
    Infections caused by strains with multi-drug resistance are difficult to treat with standard antibiotics. Garlic is a powerful remedy to protect against infections of many bacteria, fungi and viruses. However, little is known about the potentials of fresh garlic extract (FGE) to improve the sensitivity of multi-drug resistant strains to antibiotics..
    Objectives
    In this study, we used the disk diffusion method to investigate the antimicrobial activities of FGE and the combination of antibiotics with FGE, on methicillin-resistant Staphylococcus aureus (MRSA), Pseudomonas aeruginosa and Candida albicans, to evaluate the interactions between antibiotics and FGE..
    Materials And Methods
    Clinical isolates were isolated from clinical specimens obtained from the inpatients at the First Affiliated Hospital of Xi’an Jiaotong University Health Science Center. The isolates consisted of MRSA, (n = 30), C. albicans (n = 30) and P. aeruginosa (n = 30). Quality control for CLSI (Clinical and Laboratory Standards Institute) disk diffusion was performed using S. aureus ATCC®25923, C. albicans ATCC®90028 and P. aeruginosa ATCC®27853. The 93 microorganisms were divided into four groups in a factorial design: control (deionized water), FGE, antibiotics without FGE, and antibiotics with FGE. Next, antibacterial activity was evaluated by measuring the diameter of inhibition zones according to performance standards for antimicrobial susceptibility testing of the Clinical and Laboratory Standards Institute (CLSI, formerly NCCLS)..
    Results
    Fresh garlic extract displayed evident inhibition properties against C. albicans and MRSA, yet weak inhibition properties against P. aeruginosa. Additionally, FGE showed the potential to improve the effect of antibiotics on antibiotic resistant pathogens. The synergism of fluconazole and itraconazole with FGE on C. albicans yielded larger sized inhibition zones compared with fluconazole and itraconazole without FGE (P < 0.01). The factorial analysis represents intense positive interaction effects (P < 0.01). The synergism of cefotaxime and ceftriaxone with FGE on P. aeruginosa yielded larger sized inhibition zones than cefotaxime and ceftriaxone without FGE (P < 0.01). The factorial analysis represents intense positive interaction effects (P < 0.01)..
    Conclusions
    The results suggest that FGE can improve the antibiotic sensitivity of these pathogens to some antibiotics..
    Keywords: Garlic, Drug Resistance, Microbial, Candida albicans, Methicillin, Resistant Staphylococcus aureus, Pseudomonas aeruginosa
  • Nafiseh Davati, Farideh Tabatabaee Yazdi, Saeed Zibaee *, Fakhri Shahidi, Mohammad Reza Edalatian Page 5
    Background
    Camel milk is amongst valuable food sources in Iran. On the other hand, due to the presence of probiotic bacteria and bacteriocin producers in camel milk, probiotic bacteria can be isolated and identified from this food product..
    Objectives
    The objectives of the present research were the isolation and molecular identification of lactic acid bacteria from camel milk and evaluation of their probiotic properties..
    Materials And Methods
    A total of ten samples of camel milk were collected from the Golestan province of Iran under aseptic conditions. Bacteria were isolated by culturing the samples on selective medium. Isolates were identified by amplification of the 16S rDNA and Internal Transcribed Spacer (ITS) region between the 16S and 23S rRNA genes by Polymerase Chain Reaction (PCR) and were then screened and grouped by the Amplified Ribosomal DNA Restriction Analysis (ARDRA) method. To evaluate probiotic properties, representative isolates of different ARDRA profiles were analyzed. The antimicrobial activity of Lactic Acid Bacteria (LAB) against Pediococcus pentosaceus, Escherichia coli and Bacillus cereus was examined by the agar diffusion assay. Acid and bile tolerance of isolates were evaluated..
    Results
    A total of 64 isolates were analyzed based on biochemical tests and morphological characteristics. The most frequently isolated LAB was Enterococci. Weissella, Leuconostoc, Lactobacilli and Pediococci were less frequently found. Based on restriction analysis of the ITS, the isolates were grouped into nine different ARDRA patterns that were identified by ribosomal DNA sequencing as P. pentosaceus, Enterococcus faecium strain Y-2, E. faecium strain JZ1-1, E. faecium strain E6, E. durans, E. lactis, Leuconostoc mesenteroides, Lactobacillus casei and Weissella cibaria. The results showed that antimicrobial activity of the tested isolates was remarkable and P. pentosaceus showed the most antibacterial activity. In addition, E. durans, E. lactis, L. casei and P. pentosaceus were selected as probiotic bacteria..
    Conclusions
    This study revealed the presence of bacteriocin-producing bacteria and probiotic bacteria in camel milk from the Golestan province of Iran..
    Keywords: Milk, Camel, Probiotic, Antibacterial
  • Ali Reza Samarbaf-Zadeh, Manochehr Makvandi, Ahmad Hamadi, Gholam Abbas Kaydani *, Abdorrahim Absalan, Parviz Afrough, Mohammad Jahangir, Saeid Saeidimehr Page 6
    Background
    Hepatitis G virus (HGV) is a member of Flaviviridae. Prevalence of HGV in healthy people is very low, but this virus is more prevalent in patients with hepatitis. Besides, relative frequency of HGV in patients undergoing hemodialysis, and kidney recipients is very high. The role of HGV in pathogenesis is not clear. Since this virus cannot be cultivated, molecular techniques such as Revers Transcription Polymerase Chain Reaction (RT-PCR) is applied to detect HGV..
    Objectives
    The current study aimed to investigate the prevalence of HGV using determination of E2, viral envelope antigen, antibodies and the RNA by Enzyme Linked Immunosorbent Assay (ELISA) and RT-PCR techniques. The rational of the study was to determine the prevalence of HGV in patients undergoing hemodialysis and kidney transplantation in Khuzestan province, Iran..Patients and
    Methods
    Five hundred and sixteen serum samples of the patients undergoing hemodialysis and kidney transplantation from various cities of Khuzestan province were collected. Anti-hepatitis G E2 antibodies were investigated by ELISA method. RNAs were extracted from serums and Hepatitis G RNA was detected by RT-PCR..
    Results
    Of the 516 samples, 38 (7.36%) specimens were positive for anti-HGV by ELISA. All of these ELISA positive samples were negative for HGV genome by RT-PCR. Of the remaining 478 ELISA negative samples, 16 (3.14%) samples were positive by RT-PCR..
    Conclusions
    Hepatitis G Virus was not prevalent in the patients undergoing hemodialysis and kidney transplantation in Khuzestan province. Although reports indicated high frequency of co-infection of HGV with hepatitis B and C viruses, in the current research, co-infection of HGV with B and C was not considerable. Since different groups and subtypes of HGV are reported, periodic epidemiologic evaluation of HGV and its co-infection with other hepatitis viruses is suggested in other populations such as the patients with thalassemia; however, periodic epidemiologic monitoring of HGV may be helpful to control future potential variations of the virus..
    Keywords: GB virus C, Renal Dialysis, Kidney Transplantation, Hemoglobin, Ahvaz
  • Rahem Khoshbakht *, Mohammad Tabatabaei, Saeid Hosseinzadeh, Hesamaddin Shirzad Aski, Saeed Seifi Page 7
    Background
    Thermophilic campylobacters, particularly Campylobacter jejuni and C. coli are the main agents of human campylobacteriosis. Campylobacter contaminated chicken products is the most important source of foodborne gastroenteritis. Evaluation of genetic diversity among Campylobacter population is critical for understanding the epidemiology of this bacterium and developing effective control strategies against Campylobacter infections and other related disorders..
    Objectives
    The aim of this study was to investigate the polymorphism of thermophilic Campylobacter isolated from broiler fecal samples in Shiraz, southern Iran..
    Materials And Methods
    Ninety Campylobacter isolates were recovered from broiler feces using enrichment process followed by cultivation method. The isolates were species typing on the basis of polymerase chain reaction (PCR) detection of 16SrRNA and multiplex PCR for determining two thermophilic species. To evaluate strain diversity of thermophilic Campylobacter isolates, flaA PCR-Restriction Fragment Length Polymorphism (RFLP) was performed using DdeI restriction enzyme..
    Results
    All 90 Campylobacter isolates confirmed by m-PCR were successfully typed using flaA-PCR-RFLP. Eleven different types were defined according to flaA-typing method and the RFLP patterns were located at three separate clusters in RFLP image analysis dendrogram..
    Conclusions
    Campylobacter jejuni isolates significantly showed more variety than C. coli isolates. A relatively low genetic diversity existed among C. jejuni and C. coli isolated from broilers in Shiraz, southern Iran. In our knowledge, this was the first report of genetic diversity among broiler originated human pathogen thermophilic campylobacters in Shiraz, southern Iran..
    Keywords: Campylobacter Jejuni, C. coli, Restriction Fragment Length Polymorphism, Iran
  • Rashid Ramazanzadeh, Samaneh Rouhi, Pegah Shakib, Babak Shahbazi *, Farzam Bidarpour, Mohammad Karimi Page 8
    Background
    Vibrio cholerae causes diarrhoeal disease that afflicts thousands of people annually. V. cholerae is classified on the basis of somatic antigens into serovars or serogroups and there are at least 200 known serogroup. Two serogroups, O1 and O139 have been associated with epidemic diseases. Virulence genes of these bacteria are OmpW, ctxA and tcpA..
    Objectives
    Due to the importance of V. cholerae infection and developing molecular diagnostics of this organism in medical and microbiology sciences, this study aimed to describe molecular characterization of V. cholerae isolated from clinical samples using a molecular method..
    Materials And Methods
    In this study, 48 samples were provided during summer 2013 (late August and early September) by reference laboratory. Samples were assessed using biochemical tests initially. The primer of OmpW, ctxA and tcpA genes was used in Polymerase Chain Reaction (PCR) protocols. Enterobacterial Repetitive Intergenic Consensus (ERIC)-PCR and Repetitive Extragenic Palindromic (REP)-PCR methods were used to subtype V. cholerae..
    Results
    In this study, from a total of 48 clinical stool samples 39 (81.2 %) were positive for V. cholerae in biochemical tests and bacteria culture tests. The PCR results showed that of 39 positive isolates 35 (89.7%), 34 (87.1%) and 37 (94.8%) were positive for ctxA, tcpA and OmpW gene, respectively. Also, in the REP-PCR method with ERIC primer strains were divided into 10 groups. In the REP-PCR method with REP primer, strains were divided into 13 groups..
    Conclusions
    Polymerase chain reaction has specificity and accuracy for identification of the organism and is able to differentiate biotypes. Enterobacterial repetitive intergenic consensus sequence is one of the informative and discriminative methods for the analysis of V. cholerae diversity. The REP-PCR is a less informative and discriminative method compared to other methods for the analysis of V. cholerae diversity..
    Keywords: Molecular Characterization, Vibrio cholerae, Clinical Samples, Virulence Genes
  • Roghayeh Teimourpour, Zahra Meshkat *, Aida Gholoubi, Hosein Nomani, Sina Rostami Page 9
    Background
    Previous studies using cell culture systems for the replication of hepatitis C virus have opened new research dimensions, and paved the ways for further and detailed studies of the virus in vitro..
    Objectives
    The purpose of the present study was to cultivate hepatitis C virus in a cell culture system and evaluate viral amplification..
    Materials And Methods
    In order to propagate hepatitis C virus, cloned whole genome of virus, JFH-1, was used. JFH-1 cDNA was introduced into strain JM109 of Escherichia coli and plasmid, containing the viral genome was purified from transformed bacteria. After XbaI digestion, RNA synthesis was induced using T7 RNA polymerase enzyme. Next, eukaryotic cell line Huh 7.5 was transfected by the purified RNA. Finally, Huh-7.5 cell line was infected with replicated virus and viral load was determined using real-time PCR (Polymerase Chain Reaction)..
    Results
    The amount of viral load, which was measured using real-time PCR was 17592 IU/mL..
    Conclusions
    In the present study, using cell culture, a high titer (in acceptable range) of infectious hepatitis C virus was produced. This method could be used in future studies..
    Keywords: Hepatitis C Virus_DNA_Complementary_JFH_1_Huh 7.5_Real_Time Polymerase Chain Reaction
  • Mustafa Demirci, Nurten Baran, Atilla Uzum, Aylin Orgen Calli, Sureyya Gul-Yurtsever *, Tuna Demirdal Page 10
    Introduction
    Alternaria is a common saprophyte, which is usually not pathogenic in humans. Generally, local wounds infections of Alternaria occur with presence of immunosuppression factors such as HIV infection and renal transplant patients..
    Case Presentation
    We reported a case of wound infection induced by Alternaria spp. in a renal transplant patients. The main interest in this case was the rareness of the cutaneous alternariasis, its clinical aspects and good response to therapy. Recognition of Alternaria spp. as potential opportunistic pathogens is important for differential diagnosis of dermatological lesions, such as granulomatous or ulcerative lesions in immunocompromised patients..
    Conclusions
    Alternariasis or similar cases may be increased due to the increased number of immunosuppressed patients. From this point of view, skin lesions in these patients must be planned and microbiologically evaluated considering the molds..
    Keywords: Cutaneous Alternariasis, Kidney Transplantation, Transplantation
  • Seyed Hossein Abdollahi, Fateme Ayoobi, Hossein Khorramdelazad, Behzad Nasiri Ahmadabadi, Mohammadtaghi Rezayati, Mohammad Kazemi Arababadi, Mohammad Zare-Bidaki * Page 11
    Background
    Zoonotic parasite Toxoplasma gondii has a high prevalence in human populations. A suitable vaccine for animals can stop the transmission of infection between animal and human..
    Objectives
    The aim of this study was to evaluate in vivo prepared excretory/secretory antigens (E/SA) as a potential candidate for immunization against the parasite and its effect on the production of transforming growth factor-beta (TGF-β)..
    Materials And Methods
    Toxoplasma gondii tachyzoites were inoculated in the peritoneal cavity of mice and E/SA was harvested and used in animal immunization with and without adjuvant. Serum levels of anti-E/SA antibodies and TGF-β were measured in days 0, 3, 7, 14, 28 and 56 after immunization using ELISA technique. The measurements were statistically analyzed..
    Results
    Our results showed that the serum levels of anti-E/SA immunoglobulins significantly increased in all of the immunized groups. The differences of the serum levels of TGF-β between the groups were statistically significant at days 28 and 56 after immunization with E/SA..
    Conclusions
    Based on our study, in vivo prepared E/SA may be considered as a good candidate for animal immunization..
    Keywords: Toxoplasma, Immunization, Transforming Growth Factor, beta, Excretory, Secretory Antigen
  • Keivan Kiakojuri, Ramazan Rajabnia, Bahareh Jalili, Soraya Khafri, Saeid Mahdavi Omran * Page 12
    Background
    Otomycosis is an external ear canal infection caused by various fungi. This disease is prevalent in some tropical and subtropical regions or countries..
    Objectives
    Given the crucial role of fungal agents in the treatment of the disease, the aim of the present study was to identify the fungi in ear canal of patients with otomycosis admitted to the hospitals in Babol City, Iran..Patients and
    Methods
    This study included 56 patients with otomycosis. After removal of ear infectious samples, some of them were placed on the slides for direct examination and also a portion of them was plated on the Sabouraud dextrose agar with chloramphenicol for fungal growth. The slides were studied for the presence of fungal elements. Conventional methods were performed to determine fungal colonies..
    Results
    Thirty-three patients (55.36%) were female and the rest were male. Fungal elements were observed in 11 cases (19.64%) in the direct examination, alone, and 45 specimens (80.36%) had fungi and bacteria combined. Septate mycelia, with 43 cases, had the most frequent fungal elements in direct examination. Aspergillus and Candida genera were the prevalent fungal colonies in culture media..
    Conclusions
    According to the role of different genera of fungi in the process of otomycosis, much attention on the macroscopic and microscopic examination of the samples leads to special treatment decisions of a physician..
    Keywords: Otomycosis, Aspergillus, Candida
  • Ehsan Ghasemian, Ali Naghoni *, Helya Rahvar, Mahsa Kialha, Bahman Tabaraie Page 13
    Background
    Biofilm formation is a major virulence factor in different bacteria. Biofilms allow bacteria to resist treatment with antibacterial agents. The biofilm formation on glass and steel surfaces, which are extremely useful surfaces in food industries and medical devices, has always had an important role in the distribution and transmission of infectious diseases..
    Objectives
    In this study, the effect of coating glass and steel surfaces by copper nanoparticles (CuNPs) in inhibiting the biofilm formation by Listeria monocytogenes and Pseudomonas aeruginosa was examined..
    Materials And Methods
    The minimal inhibitory concentrations (MICs) of synthesized CuNPs were measured against L. monocytogenes and P. aeruginosa by using the broth-dilution method. The cell-surface hydrophobicity of the selected bacteria was assessed using the bacterial adhesion to hydrocarbon (BATH) method. Also, the effect of the CuNP-coated surfaces on the biofilm formation of the selected bacteria was calculated via the surface assay..
    Results
    The MICs for the CuNPs according to the broth-dilution method were ≤ 16 mg/L for L. monocytogenes and ≤ 32 mg/L for P. aeruginosa. The hydrophobicity of P. aeruginosa and L. monocytogenes was calculated as 74% and 67%, respectively. The results for the surface assay showed a significant decrease in bacterial attachment and colonization on the CuNP-covered surfaces..
    Conclusions
    Our data demonstrated that the CuNPs inhibited bacterial growth and that the CuNP-coated surfaces decreased the microbial count and the microbial biofilm formation. Such CuNP-coated surfaces can be used in medical devices and food industries, although further studies in order to measure their level of toxicity would be necessary..
    Keywords: Biofilms, Nanoparticles, Listeria monocytogenes, Pseudomonas aeruginosa