فهرست مطالب

Journal of Medical Bacteriology
Volume:8 Issue: 5, 2019

  • تاریخ انتشار: 1398/06/14
  • تعداد عناوین: 9
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  • Khadijeh Saravani, Elham Javadian, Mahboubeh Mohsenbeygi, Mehdi Hassanshahian* Pages 1-7
    Background

        The aim of this study was to investigate the antimicrobial effects of Momordica charantia against pathogenic bacteria.

    Methods

        Extract of M. charantia species was extracted using Rotary device. Minimum Inhibitory Concentration (MIC) and Minimum Bacterial Concentration (MBC) of extract on mentioned bacteria were determined using micro dilution broth method at six different concentrations.

    Results

        The results of this study showed that the lowest inhibitory concentration of extract against bacteria was 12.5 ppm, (Vibrio cholera, Pseudomonas aeruginosa and E. coli) the results also showed that only one inhibited. However, the highest inhibitory concentration was estimated 25 ppm against Shigella dysenteriae and Bacillus cereus   and highest bactericidal concentration was estimated 25 and 50 ppm.

    Conclusion

        The results of this study show good antimicrobial effects of M. charantia on pathogenic bacteria and these medicinal plants can be used to treat infections caused by bacteria.

    Keywords: Momordica charantia, Plant extract, Pathogenic bacteria
  • Bahman Fazeli * Pages 8-20
    Background

        Saffron is an interesting minor spice with a food coloring history and its active components have shown several useful pharmacological effects such as antidepressant, anti-inflammatory, antitumor, radical scavenger effects, learning and memory-improving effects, anti-Alzheimer, antipruritic, etc. Because of negative consumer perception of chemical preservatives, attention is shifting towards natural alternatives. Particular interest has been focused on the potential application of plant essential oils. The aim of the present study was undertaken to evaluate the interaction of hydroalcoholic extract of saffron petals and different concentrations of it against different Gram-positive and Gram-negative bacteria.

    Methods

        The hydroalcoholic extract of saffron petals and different concentrations of extract (60, 90, 120 mg/ml) by a blank sterilized disc diffusion test was assessed against four different gram-positive and negative bacterial pathogens. Also, a full randomized factorial design experiment was conducted with three replications. The statistical analysis was performed using two-way ANOVA followed by LSD test for multiple comparisons.

    Results

       The results of ANOVA showed that saffron petals hydroalcoholic extract and antibiotics were an effective on all tested bacterial strains and the most effective antibacterial properties has been observed on Listeria monocytogenes followed by Escherichia coli. The antibacterial activities of concentration of saffron petals hydroalcoholic extract was not significant on E. coli, but was significant on Listeria monocytogenes, Staphylococcus aureus and Salmonella typhimurium. Also, it was shown that the increases of the concentration of the extract caused  higher antibacterial effects.  The highest antibacterial effect of saffron petals hydroalcoholic extract was 120 mg which was observed against the L. monocytogenes. Saffron petals hydroalcoholic extract showed more antibacterial activity against the Gram-positive bacterium.

    Conclusion

        The results of this research showed that saffron petals extract has considerable  potential as a herbal-base antimicrobial compound.

    Materials & Methods

    It was used the hydroalcoholic extract of saffron petals and different concentrations of extract (60, 90, 120 mg/ml) by a disc diffusion test against four different gram positive and negative bacteria that it was conducted a factorial experiment base on completely randomized design with three replications and also in this research some antibiotics such as AN, CRO, Gm, Am, P, SXT, CP and AZM were used for positive control. The statistical analysis was performed using two-way ANOVA followed by LSD test for multiple comparisons.

    Results

    The results of AMOVA was shown that saffron petals hydroalcholic extract and antibiotics were effect on all bacteria and the most influence antibacterial has on Listeria monocytogenes and then Escherichia Coli. The antibacterial activities of concentration of saffron petals hydroalcholic extract was not significant on E. Coli, but was significant on L. monocytogenes, S. Aureus and S. typhimurium that by increasing the concentration of the extract, antibacterial effect has increased So, the highest antibacterial effect of saffron petals hydroalcholic extract was 120 mg on the L. monocytogenes bacteria. Saffron petals hydroalcholic extract showed more antibacterial activity against the Gram-positive bacterium.

    Conclusion

    The result of this research shown that saffron petals extract has great potential as antimicrobial compounds against microorganisms.

    Keywords: Crocus sativus, E. coli, L. monocytogenes, S. aureus, S. typhimurium
  • Jamileh Nowroozi, Shahnaz Armin, Leila Azimi, Sahel Valadan, Fatemeh Fallah* Pages 21-29
    Background

         Staphylococcus aureus is considered as a major cause of skin and soft tissue infections, arthritis, osteomyelitis, infective endocarditis, and pneumoniae though community or nosocomial transmission. In this study, attempts were made to investigate the distribution of some important exotoxin genes, including hla, hlb, tsst-1, eta, etb, and etd among methicillin-resistant S. aureus (MRSA) isolated from a hospital patients in Tabriz, Iran.

    Methods

        In the present cross-sectional study, a total of 90 S. aureus were isolated from children who admitted to a hospital during six-month in 2017. Isolates were identified using biochemical tests and then, using PCR, the isolates were tested for the presence of, hla, hlb, tsst-1, eta, etb, and etd genes.

    Results

         It was found that 40% of the S. aureus were considered as MRSA strains by biochemical and molecular tests. The results of molecular detection of virulence determinants showed that eta, hla, etb, tsst-1, hlb and etd were detected in 86.1%, 80.5%, 30.5%, 27.7%, 22.2%, and 19.4% of isolates, respectively.

    Conclusion

        Our findings clarify characterization of toxin production status of S. aureus isolates from patients in Iran. The current study showed that a majority of S. aureus isolates harbored eta and hla virulence gene.

    Keywords: Exotoxins, Methicillin-resistant Staphylococcus aureus6, toxic shock syndrome toxin-1, Pediatrics, Staphylococcal exfoliative toxin
  • Afsaneh Gholami, Faramarz Masjedian, Behzad Salehi* Pages 30-37
    Background

    Listeriosis, a fatal disease for vulnerable groups, has become common in the last decade due to extensive consumption of dairy and meat products. Listeria monocytogenes is an important foodborne opportunistic human pathogen and causal agent of listeriosis. There is a little information about the antibiotic susceptibility and resistance genes pattern of L. monocytogenes.

    Methods

    The present study aimed to evaluate the antibiotic susceptibility and resistance genes pattern of L. monocytogenes isolates from different clinical and environmental sources.

    Results

    The results showed that 88% of the isolates are resistant to streptomycin and 83% to TMP-SMX. Polymerase chain reaction (PCR) amplification of resistance genes showed that the prevalence of ermA, ermB, strA, tetS, tetA, and ermC genes in L. monocytogenes isolates were 0% (0/55), 10.9% (6/55), 78.81% (43/55), 0% (0/55), 27.27% (15/55), and 0% (0/55), respectively.

    Conclusion

    The resistance of the isolates to the antibiotics represents a potential public health risk and indicates the necessity of the bacteriological controls to reduce the contamination of the food samples.

    Keywords: Antibiotic susceptibility, Listeriosis, Listeria monocytogenes
  • Saeid Vahedi, Fatemehsadat Mirsane, Farnaz Soltani, Mohammad Kazem Sharifi, Mohammad Hassan Houshdar, Monireh Zeinolabedini, Laya Kafami, Mohammad Mehdi Soltan * Pages 38-43
    Background

    The aim of this study was to provide a simple and efficient way of producing IgY antibodies against Escherichia coli and extract that by polyethylene glycol (PEG) precipitation method.

    Methods

    An ti- Escherichia coli antibody was produced in hens by using formalin-killed E.coli and confirmed by ELISA method, applying serum`antibody. The specific IgY was extracted from egg yolk by Polyethylene Glycol (PEG) Precipitation and analysed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE).

    Results

    The result of ELISA shows that the IgY titre increased from initial immunization and the high titre (≥0.071) persisted after the first immunization. Heavy chain of IgY with ~68 KDa was observed in the Gel electrophoresis pattern.

    Conclusion

    The results of the ELISA indicates the specificity of the immunoglobulin Y to the target antigen and the result of SDS-PAGE represented the appropriate extraction method. More research must be done on the ability of these antibodies to inhibit the growth of E.coli.

    Keywords: Enzyme-Linked Immunosorbent Assay, Escherichia coli, Polyethylene Glycol, Serum
  • Lalsanglura Ralte, Surajit De Mandal, Nachimuthu Senthil Kumar, Tapan Dutta, Indu Sharma, Karuppasamy Chellapandi* Pages 44-55
    Background

    DAEC seems to be a neglected pathogen among diarrheagenic E. coli since its association with pediatric diarrhea is rarely reported. But, the emergence and spread of MDR diarrhea causing bacterial pathogens have become a global burden. This study investigated the prevalence of MDR DAEC among the Mizo pediatric diarrheal patients aged less than 5 years.

    Methods

    A total of 334 E. coli isolates isolated from the fecal samples were subjected to multiplex PCR assays to categorize the pathotypes of diarrheagenic E. coli and subjected to antimicrobial sensitivity assay, phenotypic and genotypic ESBL assays (blaCTX-M-9, blaCTX-M-15, blaOXA and CMY-2).

    Results

    Of 334 E. coli isolates, only 0.9% of the isolates were detected as DAEC, when compared with 0.9% and 1.2% of the isolates categorized as ETEC and EAEC from diarrheic samples and 0.6% of the EAEC also detected from the non-diarrheic samples. Among the isolates, 25%, 50% and 8.3% of the isolates were carrying the blaCTX-M-9, blaCTX-M-15 and CMY-2 respectively and 8.3% isolates from non-diarrheic samples also carried CMY-2.

    Conclusion

    Though a low frequency of DAEC was observed in comparison to other pathotypes of DEC, majority of them being resistant to commonly used antibiotics and having a high MDR rate, which is a matter of concern to the public health. This pathotype could possibly a natural source for MDR spread among the other diarrheal pathogens of pediatric population.

    Keywords: CTX-M-9, CTX-M-15, CMY-2, DAEC, MDR, Pediatric diarrhea, Mizoram
  • Neda Housseini, Ali Shivaee, Robab Rafiei, Farzaneh Hosseini* Pages 56-63
    Background

         More than 30 bacterial, viral, and parasitic pathogens have the potential for transfusion (sexually transmitted), an infectious group called sexually transmitted infections (STIs). Atofobium vagina, Gardnerella vaginalis are one of the most common causes of the disease. T. vaginalis is also the most common protozoa among vaginosis causing agents. This study aimed to determine the prevalence of these factors in conjunction with the multiplex PCR method.

    Methods

        In this study, among 320 women who referred to Shahid Akbarabadi Hospital in Tehran, 70 samples of people with symptoms of vaginosis who had not taken antibiotics at least one week before the visit were selected. The results of the Amsel criteria and Nugent score tests indicated only 27 cases as bacterial vaginosis. After DNA extraction from the specimens, a multiplex PCR was performed on the samples.

    Results

         The results of the multiplex PCR showed that in 27 cases, 14 cases of bacterial vaginosis only in terms of A. vaginalis, 21 cases were only G. vaginalis and 10 were positive for both bacteria and in the case of T. vaginalis only 1 positive sample was observed among all samples of vaginosis, which was also positive in the A. vaginalis.

    Conclusion

        The results of this study showed that multiplex PCR could be of great help in the diagnosis of bacterial vaginitis diseases.

    Keywords: A. vaginalis, G. vaginalis, T. vaginalis, multiplex PCR
  • Ava Behrouzi, Morteza Masoumi, Hasan Ghajavand, Farzaneh Mohaghegh, Parviz Afrough* Pages 64-68
    Background

          One of the most serious types of meningitis caused by Mycobacterium tuberculosis (MTB) which involves meningeal layer and is usually associated with high mortality and morbidity. We focused on the significance diagnosis and prompt treatment.

    Methods

         We describe a case of TBM.In a 40-Year-old Asian male. He was no respiratory distress, neck stiffness, constipation, and nausea, but frequent urination. In addition, the patient had a history of drug addiction.

    Results

          His Magnetic Resonance Imaging (MRI) showed hyperintense Lesions. Sputum culture for Mycobacterium tuberculosis (MTB) was found positive and he was given a therapeutic trial of quinolones and Steroids.

    Conclusion

        Observing the principles of biological safety among the personnel of medical centers and screening for TB disease in drug-positive and HIV-positive is essential.

    Keywords: Tuberculosis meningitis, TBM
  • Sarika Kombade, Vijaya Nag, Kavita Yedale, Anuradha Sharma, Jitu Kalita* Pages 69-72
    Background

        Acinetobacter species are the major cause of nosocomial infection especially in intensive care unit settings. This organism also gains its importance for its nature of showing resistance towards various classes of antibiotics.

    Methods

        Conventional biochemical test and Microscan walkway automated system was used for identification of the isolate.

    Results

        Here, we report an unusual finding of multidrug resistant Acinetobacter baumanii, isolated from cerebrospinal fluid due to the post antibiotics effect.

    Conclusion

        Microbiologist should be vigilant while reporting the unusual morphology of bacteria as antibiotic pressure effect may change the morphology and important findings may miss by microbiologist so antibiotic history should evaluated.

    Keywords: Acinetobacter baumanii, Antibiotic effect, Morphological change