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Medical Microbiology and Infectious Diseases - Volume:4 Issue: 3, Summer-Autumn 2016

Journal of Medical Microbiology and Infectious Diseases
Volume:4 Issue: 3, Summer-Autumn 2016

  • تاریخ انتشار: 1395/09/30
  • تعداد عناوین: 8
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  • Negar Seyed, Sima Rafati Pages 39-44
    Neutrophils are part of the first line of immune response and are essential for resistance against a variety of pathogens. They professionally mediate direct killing of pathogens, recruit other phagocytes by specific chemokines, produce cytokines and interact with different immune cells to shape the adaptive response. Leishmania as an obligatory intracellular parasite has evolved to benefit this early innate response to find its way into macrophages, the final host cells. Therefore it is important to reconsider the role of neutrophils for further improvement of the current vaccine status.
    Keywords: Innate immunity, Neutrophil, Leishmania, Vaccine
  • Sepideh Shahbazi, Azam Bolhassani Pages 45-51
    Immunomodulators are natural or synthetic materials that regulate the immune system and induce innate and adaptive defense mechanisms. These substances are classified into two types, immunostimulants and immunosuppressants. Immunostimulants can enhance body's resistance against various infections through increasing the basal levels of immune response. These agents could increase the oxidative activity of neutrophils, augment engulfment activity of phagocytic cells, and stimulate cytotoxic cells as necessary defense mechanisms. Many disorders could be treated using some immunostimulants such as autoimmune diseases, viral infections, and cancer. The researchers classified the immunostimulants using their origin and mode of action such as bacterial products, complex carbohydrates, vaccines (antigens and adjuvants), cytokines, immunoenhancing drugs, nutritional factors, animal extracts, and plant extracts. In this mini-review, the concepts, types, and functions of immunostimulants will be described as a therapeutic approach against different diseases.
    Keywords: Immunomodulators, Immunostimulants, Adjuvant, Mechanism
  • Faezeh Najafi, Saied Reza Naddaf, Sasan Rezaie, Eshrat Beigom Kia, Gholamreza Mowlavi Pages 52-56
    Introduction
    The nematophagus fungi have been suggested as an alternative way to eliminate the zoonotic helminths eggs from the environment. In the present study, we evaluated the ovicidal activity of a fungus, Paecilomyces lilacinus, recovered from a compost soil, on the eggs of parasitic helminths under in vitro condition.
    Methods
    Water suspension of the soil samples collected from different areas of Iran were transferred to 2% water-agar culture media baited with Rhabditis sp. larvae. The larvae-infecting fungi were harvested on potato dextrose agar (PDA) media. The sequencing of a beta-tubulin gene identified the nematophagus fungi as P. lilacinus. Eggs of three helminth species, Syphacia obvelata, Hymenolepis diminuta and Echinococcus granulosus were exposed to one isolate of the recovered fungi, and the ovicidal activity was monitored for up to 21 days.
    Results
    Out of 300 samples, only three compost soils, contained the nematophagus fungus P. lilacinus. Microscopical examinations revealed invasion of the helminths eggs by the P. lilacinus. The eggs of H. diminuta were more vulnerable to this fungus invasion while E. granulosus eggs were the least affected ones (P
    Conclusion
    Paecilomyces lilacinus can grow on fresh feces and attack the eggs of the parasitic helminths. Therefore, a combination of its hyphae with feces or administration of the spores in the animals’ food may reduce the helminths eggs in the environment and consequently intervene with the transmission of parasitic helminthes in the animal houses.
    Keywords: Nematophagous, Paecilomyces lilacinus, Syphacia obvelata, Hymenolepis diminuta, Echinococcus granulosus
  • Baharak Mohammadi, Seyed Jamal Hashemi, Hamid Reza Basseri, Mohammad Reza Abai, Mahdi Zareei Pages 57-61
    Introduction
    Nutritional requirements of fungi are essential for their successful growth in laboratories. Some fungi feed on the compounds present in the insect's bodies. The aim of this study was to evaluate the effect of insect's body powder (IBP) as a supplement for the fungi growth in culture media.
    Methods
    We used 10 mg of IBP, obtained from Anopheles superpictus and Culex theileri mosquitoes, as the optimum amount for the enrichment of Sabouraud Dextrose Agar medium containing chloramphenicol (SC). The growth rate of 27 species belonging to saprophytes and yeasts on this medium was compared with the control SC medium containing no IBP.
    Results
    From a total of 27 species of saprophytic and yeast fungi, 23 showed a positive response to the addition of IBP in the culture media, and there was a significant difference between the growth rate in the culture media containing IBP and the controls (P
    Conclusion
    IBP can be used as a supplement in fungal medium cultures for enhancing fungi growth to isolate the pathogenic fungi more rapidly. The use of IBP would be economical in the industry for making culture media. Also, it would be possible to use the fungi tested in the current study for biological control of insect's populations serving as vectors of in infectious diseases.
    Keywords: Entomophaga, Culture Media, Insect's Body Powder, Growth
  • Mohammad Reza Amiran, Abbas Akhavan Sepahi, Rezvan Zabiollahi, Hamid Ghomi, Seyed Bahman Momen, Mohammad Reza Aghasadeghi Pages 62-67
    Introduction
    The human immunodeficiency virus (HIV) is a threat to global health and the need for finding new methods of antivirus research, in particular against HIV has increased in recent years. In this study, we investigated the ability of the cold atmospheric pressure plasma jet (CAPPJ) using helium to inhibit the replication of HIV virions.
    Methods
    Single cycle replicable HIV (SCR-HIV) virions were produced by transfection of HEK293T cells with pmzNL4-3, pSPAX.2, and pMD2.G plasmids. The HeLa immortal cell line was infected with the virus SCR-HIV and then irradiated by CAPPJ at different voltages and times. The amount of the P24 antigen inside cell supernatant was measured by an ELISA method. Moreover, the cytotoxicity of this plasma jet and the viability of cells were evaluated by the XTT method.
    Results
    The inhibition of HIV by CAPPJ increased with increasing of voltage and the time of radiation. The highest voltage of 12 kv at 240 s caused virus inhibition; however, the cytotoxicity of HeLa cell line also elevated with increasing of voltage and time.
    Conclusion
    CAPPJ substantially suppresses HIV infection in vitro while causing toxicity for HeLa cell line
    Keywords: Cold atmospheric pressure plasma jet, Human Immunodeficiency Virus, Single cycle replicable virions, Plasma jet
  • Mohammad Faezi Ghasemi, Fatemeh Alikhani Pages 68-75
    Introduction
    Bacteria have at least one sigma factor (σ-factor) that transcribes the genes required for cell viability. Usually, transcription of σ-factors occurs and changes in response to a variety of environmental stresses. Expression of σ-factors is one of the strategies which is used in response to different stress conditions. This study was aimed to evaluate the effects of overexpression of σ-factors genes including σA, σB, σD, σE, σF, σG, σH, σJ, σK, σL, and σM on morphology, growth pattern and biofilm formation in Mycobacterium marinum CCUG 20998.
    Methods
    In this study, the genes for major σ-factors were cloned in the expression vector pAGHD1, containing 11 kb Hind III fragment of pAG1 and Tetz determinants. A quantitative real-time PCR (qRT-PCR) assay was used to quantify σ-factor mRNA levels of σ-factors in exponential and stationary phases. The overexpression in real-time experiments was normalized to the σA expression level. The effect of expression was evaluated on biofilm formation in this bacterium.
    Results
    Some selected σ-factors used in this study were overexpressed. The σB had the highest expression level during the exponential and stationary phases. The σ-factors σD, σG, and σH showed lower expression level compared with σE, σF, and σK. The lowest expression belonged to σL and σM σ-factors. Also, overexpression of σE and σK led to more biofilm formation in comparison to other σ-factors in M. marinum CCUG 20998.
    Conclusion
    The overexpression of some σ-factors can affect growth, morphology and biofilm formation in M. marinum CCUG 20998.
    Keywords: Mycobacterium marinum CCUG 20998, Overexpression, Sigma Factors, Biofilm
  • Marziye Taheri, Moein Saleh, Amir Hesam Nemati, Mehdi Ariana, Esfandiar Shojaei, Masoud Mardani, Mohammad Katouli, Mohammad Pooya Pages 76-82
    Introduction
    Almost 80% of nosocomial urinary tract infections (UTIs) are due to catheterization. Catheter-associated UTI (CAUTI) is the primary source for colonization of antibiotic-resistant pathogens, and uropathogenic Escherichia coli (UPEC) is the most common causative bacteria. This study was conducted to determine the phylogenetic groups, and antibiotic resistance pattern as the two important features of pathogenicity of UPEC isolates collected from urinary catheters.
    Methods
    The UPEC isolates were obtained from the urinary catheters of the patients without UTI, from two referral hospitals during 2015 to 2016. Phylogenetic grouping was performed using a multiplex PCR. Antibiotic susceptibility and extended spectrum beta-lactamase (ESBL) production were tested by the disc diffusion method. Multidrug resistance was determined based on a recent guideline. The presence of some resistance genes was examined by a PCR assay.
    Results
    Thirty-eight percent of the isolates were UPEC, all of them belonged either to B2 (62.5%) or D (37.5%) phylogenetic groups. The UPEC isolates showed a very high resistance to ciprofloxacin (80%) and the third-generation cephalosporins (72.5%). Seventy percent of the isolates were ESBL-producing, and 90% of them were multiple drug resistant (MDR). Meanwhile, the frequency of the resistance genes: ctxM, aacIV, sul1, shv, and qnrA in the isolates were 95%, 82.5%, 77.5%, 72.5%, and 45%, respectively.
    Conclusion
    High resistance to fluoroquinolones and third-generation cephalosporins, as well as high frequency of ESBL-producing and MDR UPEC isolates, are a great concern. This phenomenon is probably the consequence of the indiscriminate use and on the counter availability of antibiotics, which should be considered in empirical therapy of CAUTIs.
    Keywords: Catheter-Related Infections, Uropathogenic Escherichia Coli, Bacterial Drug Resistance, Multiple Drug Resistance, beta-Lactam Resistance
  • Usman Ali, Shahid Ahmad Abbasi, Fatima Kaleem, Tariq Butt, Sania Raza Pages 83-87
    Introduction
    Stenotrophomonas maltophilia is intrinsically resistant to many antimicrobials. Like Pseudomonas spp., this bacterium has a remarkable ability to cause infections, particularly in the respiratory and urinary tracts. This study aims to determine the antimicrobial resistance pattern of S. maltophilia isolates collected from a tertiary care setting and frequency of multi, extensively and pandrug-resistant S. maltophilia.
    Methods
    A cross-sectional study was carried out in Department of Microbiology, Fauji Foundation Hospital, Rawalpindi, Pakistan from January to June 2016. The isolates were identified as S. maltophilia using standard microbiological techniques, and the antimicrobial resistance was carried out using E-strip test against various antimicrobials. The data was analyzed and interpreted regarding frequencies and percentages.
    Results
    Out of 90 isolates confirmed as S. maltophilia, pus (33.33%) and urine (24.44%) were the most common specimens from which this bacterium was isolated. Antimicrobial resistance pattern showed a high percentage of resistance to many antimicrobials with exception to aztreonam, minocycline, polymyxin B and colistin.
    Conclusion
    Various S. maltophilia isolates from our set-up were resistant to antimicrobial agents used in the study. It is predicted that the infections caused by this bacterium shall be difficult to treat in the near future due to resistance to these antimicrobial agents. Though at this point no pandrug-resistant S. maltophilia is reported, the resistance pattern suggests that pandrug-resistant strains may appear shortly and when the time comes only newer antimicrobials can provide the answer.
    Keywords: Antimicrobial, Pandrug-resistance, Stenotrophomonas maltophilia