فهرست مطالب

Molecular and Clinical Microbiology - Volume:5 Issue: 2, 2016
  • Volume:5 Issue: 2, 2016
  • تاریخ انتشار: 1395/01/24
  • تعداد عناوین: 10
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  • Mojtaba Sirevand, Shohreh Zare Karizi, Sahar Honarmand Jahromy* Pages 528-536
    Background
    Several virulence factors have been described in pathogenesis of Staphylococcus aureus strains. Staphylococcal Enterotoxins(SEs) that is one of the most factors, are belonging to important members of bacterial superantigens. Superantigens are defined by their ability to stimulate cytokine release from both T cells and macrophages. 13 different SEs are known that their function is not only as gastrointestinal toxins but also as superantigens.
    Aim: The aim of this study was to evaluate the prevalence of SEs genes in isolates from patients in Ahwaz hospitals.
    Material: This study was performed on 1280 clinical samples from patients who were referred to the four hospitals in Ahwaz. Samples were collected from urine, blood, skin chips and sputum of patients. Staphylococcus aureus isolates were identified by routine bacteriological methods. Genomic DNA was extracted by Phenol-chloroform method. The sets of enterotoxin genes(sea-sei) were amplified by multiplex PCR. PCR products were analyzed by electrophoresis.
    Results
    In this study 231 Staphylococcus aureus were isolated from urine , blood, skin chips and spatum samples. 89(39%) strains had enterotoxin gene. The frequency of sea (17%), seg (15%), sec (6%), sed and seh (5.6%), seb (5.1%) and sei (9.5%) were reported. There was no see gene among isolates. The study of genes simultaneously showed that the frequency of two genes and three genes were 20% and 17 %.
    Conclusion
    Given the importance of nosocomial Staphylococcus aureus infections and the role of SEs as superantigen in the development of various diseases, study of these genes in clinical specimen is necessary.
    Keywords: Satphylococcus aureus, enterotoxin genes, super antigen, Ahwaz hospitals, Multiplex PCR
  • Masoud Dadashi *, Mina Amjadi Kashani, Gita Eslami, Hossein Goudarzi, Fatemeh Fallah, Parviz Owlia, Nafiseh Adhami, Tahoura Mousavi Pages 537-542
    Introduction
    Vaginitis is an inflammatory and infectious disease in human host that involved vaginal mucosa. Increase of resistance to various antibacterial agent has been very significant in three or four recent decades and this important subject reveals the use of new and natural sources such as plants with medical and antimicrobial property for eradication of these infections. Therefore, the aim of this study is to evaluate the antibacterial effect of green tea plant on vaginitis agents.
    Materials And Methods
    This experimental study was performed on 60 samples obtained from patients with genital infection. Then, samples were introduced to transport medium and transported to microbiology laboratory of Shahid Beheshti University of Medical Science. Incubation was performed after culturing the samples in specific medium. Microorganisms were identified responsible for vaginitis and isolated after growth of colonies and performing the confirmation tests. Finally, disk diffusion and MIC tests were performed for detection of susceptibility and resistance of infections to 6 mentioned antibiotics in comparison with green tea extract.
    Risults: The antibacterial effect of green tea extract on lactobacillus and listeria was more effective in comparison with current antibiotics except ciprofloxacin. Green tea extract had antibacterial effect on B group streptococcus as like as gentamicin and ampicillin.
    Conclusion
    Green tea extract can be used as an effective antimicrobial agent in conjunction with other antibiotics for the treatment of vaginal infections in women.
    Keywords: Vaginitis, Green tea, extract, Antibiotic susceptibility, Infection
  • Negin Naghdi, Masood Ghane* Pages 543-548
    Propionibacterium acnes is propounded as one of the significant factors in occurrence of acne. Today, due to development of the antibiotic resistance, most of the acne treatments are faced with failure. In order to determine the antibiotic resistance of the P.acnes strains isolated from the patients with acne, this research has been carried out. 70 samples collected using microbial culture technique were studied in order to identify P.acnes. Antibiotic resistance of the strains isolated by antibiogram method to the antibiotics, including Erythromycin, Clindamycin and Tetracycline being the preferred antibiotics in the acne treatment was determined. Of total 70 studied samples, 14 positive samples (20%) were identified in terms of presence of the P.acnes. Rate of antibiotic resistance to Erythromycin, Clindamycin and Tetracycline was determined to be 50%, 35.71% and 14.29% respectively. Outbreak of antibiotic resistance of the P.acnes to Erythromycin and Clindamycin is in high level. Since P.acnes is sensitive to Tetracycline in a noticeable amount, it is recommended this antibiotic is to be used to treat acne.
    Keywords: Antibiotic resistance, Minimum Inhibitory Concentration, Propionibacterium acnes, Acne vulgaris
  • Aptin Rahnavard* Pages 549-555
    Staphylococcus aureus are important factors for infections that acquired of hospital and community. Infections caused by methicillin-resistant Staphylococcus aureus mainly of hospital origin, which in many countries is increasing. For this reason, many researchers have tried to find new compounds as a substitute for these antibiotics. Hypericin is the active substance H.perforatum and licone material from the group of flavonoids that have high antiviral and antibacterial properties. Due to high demand and the Limitation of pastures, H. perforatum cultivated under different fertilizer treatments, and showed that by increasing the amount of fertilizer, the amount of nitrogen and potash hypericin will rise in the fourth level of manures. The about antibacterial effect was conducted the sodden of plants in different dilution and disk diffusion method. Each test was repeated three times, the mean diameter of inhibition zone was measured on Mueller Hinton culture medium. Bacteria in various dilutions have significant effects that the greatest impact on pure dilution and the lowest occurred in a dilution of 0.125 mg.Activity percent effective decoctions of herbs against the MRSA, MSSA and total strains were measured and the most was in MRSA strains.
    Keywords: Hypericin, Cultivated, Staphylococcus aureus, Methicillin, Resistant, Hypericum perforatum
  • Ahmad Reza Jabbari *, Elahe Rezaei, Majid Esmaelizad Pages 556-563
    Pasteurella multocida is an opportunistic pathogen responsible for pneumonia of lambs and goats, respiratory atrophic rhinitis of swine. Although the molecular basis of the pathogenicity and host specificity of P. multocida is not well understood, several studies have reported that a number of proteins are correlated with the pathogenic mechanisms. Adhesins have a crucial role in mediating colonization and invasion of the host. Thus, their presence on the bacterial surfaces is usually correlated with virulence.
    The aim of this study was identify the adhesion associate genes and antimicrobial suscaptability among ovine P. multocida isolates from Iran.
    Of the thirty tested strains, 3.4% (1/30) were susceptible to all (12 antibiotics) tested drugs, and 83.4% (25/30) were resistant to at least one drug tested. The resistance was more frequent to streptomycin (83.3%), followed by tylosin and penicillin (46.6%).
    The results of PCR analysis for the frequency of virulence-associated genes indicted that the genes encoding adhesins (ptfA, fimA, hsf-1 and ompH), were each found in more than 93.0% of the isolates. In contrast, the frequency of 2 genes (pfhA and tadD) were 36%. All the tested isolates were positive for fimA and ompH (100%). Five different virulence profiles (P1 - P5) were obtained among the 30 isolates of ovine origin, and profile P2, harboring all adhesion genes except pfhA and ptfA, had the highest frequency. The results of this investigation provide useful information for understanding the antimicrobial resistance patterns, capsular types and adhesin genes prevalence of P.multocida isolate from sheep in Iran.
    Keywords: Pasteurella multocida, Sheep, Virulence, Adhesins, Pneumonia
  • Eehsan Moghanluu, Farshad Nojoomi Pages 564-569
    Diarrheal disease is one of the main causes of death in developing countries. This study was performed to the prevalence of bacterial causes of diarrhea in patients admitted to the Military hospitals and Imam Khomeini Medical Center Hospital. This cross-sectional study was conducted in a period of 9 months from June 2014 to February 2015, 435 non-duplicative diarrheal stool samples were collected from the Imam Reza, Besat Nahaja general, Khanevadeh Artesh and Imam Khomeini Medical Center Hospitals. To separation and differentiation bacterial species selective and differential medium was used. Of the 435 stool samples collected, 204 (46.9%) were female and 231 (53.1%) were men. The prevalence of Shigella, C. jejuni, Salmonella and EHEC were 98 (22.5%), 41 (9.4%), 21 (4.8%) and 6 (1.8%), respectively. The frequency of S. flexneri were 56.1% and S. sonnei were 4.9%. The prevalence of bacterial infection among cases of diarrhea was 22.5%, which the most infection rate was related to S. flexneri.
    Keywords: Shigella, C. jejuni, Salmonella, EHEC, diarrhea, Iran
  • Melody Salahshour, Maryam Roudbary*, Kyomars Amini Pages 570-574
    Candida albicans has the ability to change between yeast and hyphal cells and is known to be a virulence property. Efg1gene of C.albicans is as a main transcription factor that plays pivotal roles in biofilm formation The aim of the current study is to investigate the presence of Efg1 gene in Candida albicans isolates from women with vaginal candidiasis and its impact on biofilm formation.
    We used 50clinical isolates subjected to PCR-RFLP to confirm C.albicans. Total RNA was extracted from C. albicans isolates by glass bead and lysis buffer, and cDNA was synthesized using Reverse Transcriptase enzyme. RT-PCR was used to evaluate the expression of Efg1 gene. Biofilm formation was evaluated in 96-well microplate and then tetrazolium reduction was assayed. All data were analyzed using t-test .
    50 clinical isolates out of 150 were confirmed as C.albicans by using PCR-RFLP. 47(94%) isolates out of 50 present Efg1 gene by using PCR, and 12(25.53%) isolates out of 47 expressed Efg1 gene by the RT-PCR. Isolates which have Efg1gene successfully form dense biofilm on microplate. The results of the tetrazolium reduction assay test showed that 2 isolates with Efg1 gene expression and 2 isolates lacked Efg1 gene expression which was significant at P-value of0.014 (P
    Keywords: Biofilm formation, Candida albicans, EFG1 gene, RT, PCR, vaginal candidiasis
  • Ariyo Shahin, Jafari *, Mansour Bayat, Mohammad Hassan Shahhosseini, Parviz Tajik, Shahla Roudbar, Mohammadi Pages 575-584
    To date, registered users of mobile phone communication network exceeded from total numbers of the world population, while a little knowledge of the biological effects of, 900-1800 MHz microwave radiation, originating from the handsets or the base transceiver stations, have been released. The current study was designed for evaluation of 900-MHz radiation effects on Candida albicans proliferation, adherence and alpha-Int1 gene expression.
    Candida albicans (ATCC:10231) grown in Yeast Peptone Dextrose (YPD) broth was distributed into five tubes (5 ml, 10^6 cells/ml) and exposed to 900 MHz GSM radiation for 6, 12, 18 and 24 hours, while the fifth tube was kept far from the radiation. Cell densities at 0, 6, 12, 18 and 24 hours were assayed (using turbidimetry in 600 nm). Equal cell densities (2.5 x 10^6 cells/ml, 200 ul) from exposed and unexposed yeasts were transferred into 96 well plates and incubated for 4 hours, in order to biofilm formation by the yeast. Yeast densities in biofilm network were assayed using the MTT method. Abundance of alpha-int1 mRNA was also estimated in the five yeast samples using q-RT-PCR method.
    Microwave exposure led to increased proliferation rate and increased biofilm formation by the yeast and the effect was prominent in 18 hours exposed samples. Quantitative RT-PCR results showed significantly increased levels of the alpha-int1 mRNA in microwave exposed yeasts.
    The significant increases in the yeast proliferation and biofilm formation after exposure to 900 MHz GSM radiation are partly mediated by changes in alpha-int1 protein expression.
    Keywords: Candida albicans, Alpha, INT1 protein, Virulence factors, Microwaves, Quantitative PCR
  • Somyeh Namroodi Pages 585-590
    Visceral leishmaniasis (VL) is an emerging zoonosis disease in countries of the Mediterranean basin caused by Leishmania infantum. Although domestic dogs are the main vertebrate hosts, many wild carnivores have been considered playing a role in the spreading of VL. Sporadic numbers of dog and human VL have been reported in Golestan Province in North Iran. The present study was performed to detect the L. infantum DNA in wild carnivores. Forty road-killed carnivores including jackals (Canisaureus= 20), red fox (Vulpesvulpes= 3), wild cat (Felissilvestris= 4), jungle cat (Felischaus= 7), stone marten (Martesfonia= 2) and least weasel (Mustelanivalis= 4) were necropsied and tested for L. infantum using PCR. PCR testing was performed on the spleen tissue samples, targeting the minicircle of kinetoplast DNA (kDNA). None of the animals showed typical VL lesion at postmortem examination. Among forty carnivores, just 2 male jackals were detected positive by PCR. The kDNA positive jakals were found in the dry areas with lower rainfall comparing those were source of negative samples. Briefly, this study for the first time reports L. infantum infection occurrence in jackals in Golestan Province where VL is occurring as an emerging disease. The results support the possible active role of wild canids such as jackals in L. infantum life cycle. More studies on wild mammals’ population seem necessary for better understanding of their role in L.infantum disseminating.
    Keywords: Leishmania, infantum, Carnivore, Golestan, Province
  • Mohammad Farahbakhsh, Laleh Alizadeh, Zahra Arab, Mazar, Mehrdad Haghighi, Simindokht Shoaei Pages 591-595
    Neurobrucellosis (N.B) is a rare and severe form of systemic Brucella infection. We introduced an unusual case that “Psychologic Symptoms” was the most prominent complaints of his family. He was a 50-year-old man who has worked in butchery. His problems had begun 2 months prior to his admission with mood disorders, arthralgia, weakness, headache, and night sweats; he has recurrent crying with no obvious environmental problem!
    Wright agglutination test, Coomb’s Wright and 2ME were negative 2 times in outpatient work-ups and the other lab tests weren’t useful in diagnosis. Treatment trials for acute sinusitis and aseptic meningitis have had some improvements of symptoms but his clinical condition was not acceptable. A brain MRI was performed; results indicated few T2W hypersignal points of white matter specially periventricular.
    Brucellosis serologic tests were requested “for third time” and the results were positive.
    The patient has treated with cotrimoxazole, doxycycline, and rifampicin for 6 months. Two weeks after this treatment, all of mentioned symptoms subsided. The brain MRI 6 weeks after treatment was repeated, and the previously seen lesions had improved. The lumber puncture 3 months after treatment was repeated and results were normal.
    Conclusion
    It can be concluded that when a patient in an endemic area suffers from chronic mood disorders, headache, fever, and other non-specific manifestations that cannot be explained by other etiologies; it may be a case of NB. In this case, the “repeated” Wright test and excellent response to NB treatment confirmed the diagnosis.
    Keywords: Neurobrucellosis, Headache, Brucella infection, mood disorders, Depression