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Jundishapur Journal of Microbiology - Volume:12 Issue: 5, May 2019

Jundishapur Journal of Microbiology
Volume:12 Issue: 5, May 2019

  • تاریخ انتشار: 1398/03/06
  • تعداد عناوین: 8
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  • Afshar Etemadi, Rezvan Moniri*, Heinrich Neubauer, Yasaman Dasteh Goli, Saeed Alamian Page 1
    Context
    Diagnosis of human brucellosis still challenges clinicians and scientists with several considerable aspects, particularly in endemic countries. The current study aimed at reviewing laboratory tests in the diagnosis of human brucellosis.
    Evidence Acquisition
    A literature search was conducted in PubMed, Scopus, Thompson Reuters, and Mesh databases using keywords for articles published until December 2018. Seventy studies were selected for data collection.
    Results
    The current inclusive review included information about the currently used advanced diagnostic tests to confirm the detection of human brucellosis.
    Conclusions
    The article reviewed the methods for the diagnosis of human brucellosis and summarized developments for the future.
    Keywords: Brucellosis, Diagnosis, Molecular Techniques
  • Zeinab Hamzehloo, Ghasem Mosayebi, Behzad Khansarinejad, Mina Zolfaghari, Hamid Abtahi* Page 2
    Background
    Helicobacter pylori is the main cause of stomach ulcers and gastric cancer. Hence, the diagnosis, treatment, and prevention of H. pylori infection can considerably reduce the fatality.
    Objectives
    This study aimed to construct a dual-antigen protein by combining the antigenic regions of UreB and FlaA of H. pylori and determine its antigenicity as a promising vaccine and serodiagnosis candidate.
    Methods
    The antigenic regions of FlaA and UreB were detected by immunological bioinformatics, amplified and joined together by polymerase chain reaction (PCR) with special primers containing linker sequences. Then, it was cloned into pET-32a and after expression and purification of the recombinant multi-epitope protein (rFlaA-UreB), its antigenicity was evaluated by immunoblotting using the sera of infected patients.
    Results
    DNA sequencing and enzyme digestion analysis showed the rFlaA-UreB gene was successfully inserted into pET32a. The recombinant protein was produced and purified via affinity chromatography and its molecular weight was similar to what had been predicted. Moreover, data indicated that rFlaA-UreB was recognized by all patients’ sera and its sensitivity and specificity were high.
    Conclusions
    Although the developed recombinant multi-epitope protein was very smaller and lighter than the natural forms of these two critical antigens, they all had close antigenic properties. Therefore, this recombinant protein can be an important antigen in the diagnosis and vaccination against H. pylori.
    Keywords: Flagellum, Recombinant Protein, Urease, Helicobacter pylori
  • Mahdieh Abolfathi, Nader Bagheri, Sara Iranparast, Amin Soltani, Ahmad Sanaei, Ghorbanali Rahimian, Soleiman Kheiri, Hedayatollah Shirzad* Page 3
    Background
    Diseases caused by Helicobacter pylori infection, including gastritis and gastric ulcer, can be harmful to epithelial cells in gastric mucosa. Furthermore, pro-inflammatory cytokines can affect the severity of some diseases caused by H. pylori infection. NLRP3 inflammasome detects H. pylori and activates caspase-1 that leads to the release of interleukin-1β (IL-1β) and interleukin-18 (IL-18) in the stomach.
    Objectives
    Since genetic variations such as polymorphisms may be involved in the expression of genes, this study was conducted to investigate the effect of NLRP3 rs10754558 polymorphism in pathogenesis of H. pylori infection.
    Methods
    Four hundred and sixty-four Iranian patients (300 patients infected with H. pylori and 164 patients uninfected with H. pylori) were genotyped by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Cytokine mRNA and protein expression were evaluated in patients infected with different genotypes of NLRP3 rs10754558 using real time-PCR and western blotting, respectively.
    Results
    The NLRP3 rs10754558 gene polymorphism was not associated with H. pylori infection or diseases caused by this bacterium. It was found out that the level of IL-1β in patients infected was higher than the uninfected individuals. Moreover, no relation was found between these single nucleotide polymorphisms and cytokine expression in H. pylori infected subjects. The findings of this study show that NLRP3 rs10754558 polymorphism may be related to the severity of acute inflammation in these patients.
    Conclusions
    Our findings show that rs10754558 polymorphism might not participate in regulating inflammation and immune responses in patients with H. pylori by influencing the expression of components of the NLRP3 inflammasome.
    Keywords: Helicobacter pylori, Gastritis, Peptic Ulcer Disease, Polymorphism, NLRP3 rs10754558
  • Mehrnoush Maheronnaghsh, Mahnaz Fatahinia *, Parvin Dehghan, Ali Zarei Mahmoudabadi, Mahnaz Kheirkhah Page 4
    Background
    Candida yeast is a normal flora of the mucous membrane of the oral cavity. Various enzymes secreted by Candida species play the role of virulence factors in different Candida infections including in cancer patients.
    Objectives
    This study aimed at comparing phospholipase, proteinase, esterase, and hemolytic activities in different Candida species isolated from the oral cavity of cancer patients and normal people.
    Methods
    This study was conducted on 36 cancer patients and 36 healthy people. MspI restriction enzyme for PCR-RFLP method was used to identify the Candida species. The enzymatic activity index (EAI) was measured for each enzyme using the relevant protocols.
    Results
    Candida albicans was the most frequent species with the frequency of 26 (72%) and 31 (81.1%) in cancer patients and healthy people, respectively. In healthy individuals and patients, the mean phospholipase activity of Candida isolates was 0.795 and 0.775, proteinase activity was 0.7531 and 0.7558, esterase activity was 0.6142 and 0.7186, and hemolysin activity was 0.6317 and 0.5756, respectively.
    Conclusions
    The results showed that C. albicans was the most frequent Candida species isolated from healthy people and patients. Phospholipase, proteinase, and hemolysin activity of Candida species was higher in patients than in healthy people and hemolytic activity was significantly higher in patients than in healthy subjects (P < 0.05). However, Candida species in both groups were positive for esterase activity but the mean activity of this enzyme was significantly higher in the healthy group than in the patient group.
    Keywords: Candida Species, Hemolysin Factor, Phospholipase, Proteinase, Chemotherapy
  • Kourosh Manouchehri Naeini, Ehsan Heidari Soureshjani, Mahnaz Jafari, Shahrbanou Parchami, Gharib Karimi, Rahman Abdizadeh* Page 5
    Background
    Toxoplasmosis is a ubiquitous zoonotic disease caused by Toxoplasma gondii. Blood and blood products can be a probable route of T. gondii transmission, especially in patients undergoing multiple transfusions.
    Objectives
    The aim of this cross-sectional study was to determine the prevalence of T. gondii infection among healthy blood donors in Chaharmahal and Bakhtiari province.
    Methods
    We collected 385 blood samples from blood donors referring to the three biggest Blood Transfusion Organization Centers in the province during the period from January to June 2017. IgG and IgM antibodies against T. gondii were examined using enzyme-linked immunosorbent assay. Moreover, all samples were tested by loop-mediated isothermal amplification (LAMP) method for the detection of DNA of T. gondii.
    Results
    The seroprevalence rates of IgG and IgM anti-T. gondii antibodies were 37.9% and 1.56%, respectively. With the LAMP method, 1.56% of the samples were positive for the DNA of T. gondii. Of these, four (1.04%) were seropositive for both IgG and IgM and two (0.52%) were positive only for IgG. Moreover, statistical analyses indicated that several risk factors including gender, age, contact with cats, and consumption of undercooked meat were significantly related to T. gondii seropositivity in blood donors.
    Conclusions
    This study indicated that anti-T. gondii antibodies were highly prevalent among apparently healthy blood donors in Southwest Iran. There was a possibility of infection transmission by blood transfusion while there is a lack of screening tests for Toxoplasma infection in the Blood Transfusion Organizations. It is strongly suggested that appropriate and sensitive screening programs be designed by the LAMP method for the detection of T. gondii in blood donors.
    Keywords: Blood Donors, Toxoplasmosis, Seroprevalence, Loop Mediated Isothermal Amplification, Chaharmahal, Bakhtiari Province
  • Reza Ranjbar *, Ali Seif, Farhad Safarpoor Dehkordi Page 6
    Background
    Regarding the presence of immunosuppressed patients in hospitals, hospital food must have a boost safety. Escherichia coli O157 is one of the prevalent causes of food-related poisoning.
    Objectives
    The current examination was done to assess the distribution of virulence factors and phenotypic analysis of antibiotic resistance of E. coli O157 bacteria recovered from hospital food.
    Methods
    From April to August 2016, 200 hospital food samples were obtained and directly transported to the laboratory. Escherichia coli O157-positive bacteria were analyzed by disk diffusion and polymerase chain reaction (PCR).
    Results
    Nine out of 200 (4.50%) samples harbored E. coli O157. Distribution of E. coli O157 in soup and gavage samples were 3% and 6%, respectively. Stx1 (100%), eaeA (100%), and ehlyA (100%) were the most frequently detected virulence genes. Escherichia coli O157 bacteria exhibited maximum prevalence of antibiotic resistance against tetracycline (100%), gentamycin (100%), ampicillin (100%), mezlocillin (50%), enrofloxacin (50%), and trimethoprim (50%). Distribution of resistance of E. coli O157 bacteria against more than six antibiotic agents was 11.11%.
    Conclusions
    Gavage and soup samples may be sources of virulent and resistant E. coli O157. High presence of E. coli O157, simultaneous presence of multiple virulence genes, and resistance against animal-based antibiotics presented inadequacy of cooking time and temperature in processing of hospital foods.
    Keywords: Virulence Factors, Antibiotic Resistance Properties, Hospital Food, Escherichia coli O157
  • Ebrahim Rezazadeh Zarandi, Shahla Mansouri, Nouzar Nakhaee, Farhad Sarafzadeh, Mohammad Moradi* Page 7
    Background
    The non-toxigenic variant of Clostridium difficile is prevalent in clinical samples. The reason for the high prevalence of these strains in the clinical diarrhea specimens has not yet been studied.
    Objectives
    Evaluation of spore production in non-toxigenic C. difficile isolates (A-/B-/CDT-) compared to toxigenic isolates (A+/B+/CDT-) in the absence and presence of antibiotics.
    Methods
    Minimum inhibitory concentration (MIC) for bacteria was performed by the microdilution technique. About ~106 bacteria from 18-hour culture were inoculated to pre-reduced media containing ½ × MIC of vancomycin (VAN), clindamycin (CLI) and ceftazidime (CAZ). After 24, 48, and 96 hours, one milliliter of broth culture was added and heated for killing vegetative forms. One hundred microliters of appropriate dilution were cultured on Columbia blood agar in triplicate. After 72 hours, the number of viable spores was counted based on the colony forming unit.
    Results
    The result showed the spore production of non-toxigenic C. difficile isolates in free antibiotic media and ½ × MIC of antibiotics was similar to toxigenic isolates. The VAN, CLI, and CAZ inhibited spore production in non-toxigenic isolates as much as toxigenic isolates of C. difficile.
    Conclusions
    It seems the non-toxigenic C. difficile isolates are able to produce spores in the absence and presence of antibiotic in a similar manner to toxigenic isolates. Generally, their ability to produce toxin is lost, but they are able to remain, sporulate, and survive in hospitalized patients who receive antibiotics.
    Keywords: Clostridium difficile, Antibiotics, Spore Production
  • Tingting Chen, Wenfang Tang, Yimin Chen, Jun Zhang, Xinyou Xie Page 8