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Medical Microbiology and Infectious Diseases - Volume:3 Issue: 3, Summer-Autumn 2015

Journal of Medical Microbiology and Infectious Diseases
Volume:3 Issue: 3, Summer-Autumn 2015

  • تاریخ انتشار: 1395/03/17
  • تعداد عناوین: 8
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  • Fatemeh Jahanbakhsh, Sana Eybpoosh, Ehsan Mostafavi, Aliakbar Haghdoost, Kayhan Azadmanesh Pages 44-47
    We conducted this study to obtain a comprehensive picture of molecular epidemiology of HIV-1 in three neighboring countries, i.e. Afghanistan, Iran, and Pakistan as a basis for discussing possible hypothesis regarding between-country virus transmission. Our results showed that subtype composition differs between these countries with more variation in Pakistan than Iran and Afghanistan. The CRF35-AD clade was predominant in Afghanistan and Iran while the A1 subtype was predominant in Pakistan. HIV-1 sequences obtained from Pakistan (belonging either to B, A1, or CRF35_AD clades) did not group with the sequences obtained from Afghanistan and Iran. However, CRF35_AD clades from Afghanistan made two significant clusters with those strains from Iran. The results also showed that CRF35_AD clades from Afghanistan had more diversity than those in Iran suggesting its older presence in this country. Putting these findings together and considering drug trafficking/immigration events from Afghanistan to Iran we hypothesized that HIV epidemics might have been transmitted from Iran to Afghanistan. However, the reverse order might also be true but with less support from the existing evidence. There was no indication of Iran-Pakistan HIV transmission. Performing sophisticated evolutionary analysis is needed to test these hypotheses about the origin and transmission pattern of the virus among these countries.
    Keywords: Molecular Epidemiology, HIV-I, Afghanistan, Iran, Pakistan
  • Vijayalakshmi Payala, Sreedevi Hanumantha, Pilli Hema Prakash Kumari Pages 48-51
    Introduction
    Occurrence of detectable amounts of viral antigen or viral particles in the blood of infected patients with Hepatitis B virus (HBV) is a significant characteristic of HBV infection. Detection of HBV antigen or its DNA among individuals of a community is a crucial factor to know the burden of HBV infection. Hepatitis B surface antigen (HBsAg) is a suitable marker of HBV infection but a poor indicator of infectivity since its presence is not a direct measure of the presence of viable virions. Hence the tests for the detection of HBV DNA or HBsAg are used. The measurement of HBV DNA in serum has become the main tool to identify viral load, to monitor patients’ therapy and to predict whether antiviral therapy would be successful or not.
    Methods
    The present study was designated to identify HBV infected individuals among adolescent age group by using combined methods namely, rapid immunoassay technique for HBsAg detection (HEPACARD) and Conventional Polymerase Chain reaction (PCR) analysis for HBV DNA detection.
    Results
    Serum samples from 39 patients suspected of HBV infection were tested for the presence of HBsAg and HBV DNA. Eight specimens (20%) were positive for HBsAg as well as HBV DNA using PCR reaction. The ratio of spectrophotometric analysis of the extracted DNA samples was between 1.80-1.92 indicating a highly purified DNA. The gel electrophoresis of amplified PCR products of HBV DNA revealed a single 524 bp band in the test samples.
    Conclusion
    Screening for HBV infection among adolescents by HEPACARD and further confirmation by PCR is recommended to monitor the progression of the disease and antiviral treatment.
    Keywords: Hepatitis B Virus_Viral DNA_HBsAg_PCR
  • Susan Darudi, Mehdi Mohebali, Homa Hajjaran, Abdolmajiid Fata, Elham Kazemi-Rad, Reza Raoofian Pages 52-56
    Introduction
    Anthroponotic cutaneous leishmaniasis (ACL) is still a major public health problem in the northeast and central parts of Iran. This study was designed to compare microscopy and cultivation methods with PCR amplification of kinetoplast DNA and ITS1 followed by RFLP analysis for diagnosis of acute and chronic ACL.
    Methods
    In this study, 66 patients with ACL including 24 acute and 42 chronic forms were analyzed. Chronic forms (n=42) were divided into lupoid (n=18) and non-lupoid forms (n=24). The exudates from patient’s lesions were examined by parasitological and molecular methods.
    Results
    Out of 24 acute ACL cases, 24 (100%), 20 (83.3%), 24 (100%) and 23 (95.8%) were positive with direct examination, cultivation, kDNA-PCR, and ITS1-PCR-RFLP, respectively; while among 42 chronic forms, 29 (69%), 12 (28.5%), 27 (64.2%) and 16 (38%) were positive with the above mentioned methods. The most positivity rate was obtained with the direct examination for all clinical forms of ACL. In comparison with the direct examination as a gold standard, the kDNA-PCR showed the highest sensitivity of 100% and 64.2% in the diagnosis of acute and chronic forms, followed by the ITS1-PCR with lower sensitivity (95.8% and 38%) and then cultivation (83.3% and 28.5%). Also, all of the Leishmania isolates were identified as Leishmania tropica based on clinical symptoms and molecular methods.
    Conclusion
    Our results recommend application of direct examination for the diagnosis of both acute and chronic forms of ACL. Moreover, the molecular method using kDNA-PCR was proposed for the diagnosis of ACL; while ITS1-PCR-RFLP can be utilized as a useful technique for the Leishmania species identification of CL.
    Keywords: Leishmania tropica, Acute, Chronic, Iran
  • Barat Ali Fakheri, Samaneh Bagheri, Nafiseh Mahdi Nezhad Pages 57-61
    Introduction
    Increasing of food-related diseases has led to the perception of diet importance. Plant-derived products (especially tea) as important sources of antioxidant and antimicrobial compounds play a major role in reducing food pathogens. In this study, total phenolic content, antioxidant and antimicrobial activity of four tea extracts including green tea, white, black and red teas were evaluated.
    Methods
    The total phenolic amount was determined using Folin–Ciocalteu method and 1-diphenyl-2-picryl hydrazyl radical (DPPH) method was used for antioxidant activity measurement. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of tea extracts against eight species of tested bacteria (Staphylococcus aureus, Streptococcus pyogenes, Streptococcus pneumonia, Saprophyticus Staphylococcus, Enterococcus faecali, Acinetobacter baumannii, Proteus mirabilis and Serratia marcescens) were evaluated by microdilution technique.
    Results
    The results of this study showed that green tea and white tea extracts had the highest total phenolic content and antioxidant scavenging activity. Also, a strong positive correlation was observed between phenolic content and antioxidant activity in green tea and red tea.
    Conclusion
    All four tea extracts showed inhibitions of several microorganisms. However, gram-negative bacteria were more resistant to inhibitory effects of tea extracts. As a result, non-fermented tea extracts showed more antioxidant activity and inhibition effect against tested bacteria.
    Keywords: Antioxidants, Phenols, Plant extracts, Tea
  • Matin Saberi, Hojjatolah Zamani, Ali Salehzadeh Pages 62-66
    Introduction
    Pseudomonas aeruginosa is one of the leading causes of nosocomial infections, and antibiotic resistance of this pathogen is an important concern in treating such infections. The current work was conducted to investigate the prevalence of bla-IMP, and bla-VIM metallo-beta-lactamase (MBL) among clinical and environmental P. aeruginosa isolates obtained from ICUs of different hospitals in Rasht, Iran.
    Methods
    A total number of 35 P. aeruginosa strains including 20 clinical and 15 environmental strains were isolated from ICUs. The isolated bacteria were screened for MBL production using Combined Disc Synergy Testing (CDST) assay. The frequency of bla-IMP and bla-VIM among MBL producing P. aeruginosa (MBL-PA) was investigated using Polymerase Chain Reaction (PCR). Also, the antibiotic susceptibility of all isolates was determined.
    Results
    According to the results, 51% of isolates were regarded as MBL-PA while bla-IMP or bla-VIM genes were detected in 37% of isolates. The environmental isolates showed higher resistance to the majority of antibiotics compared to the clinical isolates, and MBL genes were more prevalent among environmental isolates.
    Conclusion
    Higher resistance of environmental P. aeruginosa strains in ICUs shows a need to pursue newer approaches, including novel cleaning methods and surveillance programs, to reduce nosocomial infections.
    Keywords: Carbapenems, Antibiotic resistance, Metallo-Beta-Lactamase, Nosocomial infection
  • Safiyeh Abbasi, Behnam Zamanzad Pages 67-70
    Introduction
    Methicillin-resistant Staphylococcus aureus (MRSA) is an important pathogen that causes several nosocomial or community-acquired infections. Adhesion to surfaces and subsequent biofilm formation are the major phases of a staphylococcal infection. The aim of this study was to detect the presence of icaABCD genes in clinical isolates of MRSA.
    Methods
    A total of 110 clinical Staphylococcus aureus isolates were collected from two teaching hospitals in Shahrekord (Hajar and Kashani hospitals). The MRSA isolates were detected by an antibiotic susceptibility test. A microtiter tissue plate assay was used to detect the phenotypic biofilm formation. A polymerase chain reaction (PCR) was performed to detect the presence of icaABCD genes.
    Results
    The microtiter plate assay results showed that attachment abilities were strong in 26 (23.6%) strains, moderate in 30 (27.2%) strains, and weak in 16 (14.54%) strains. The prevalence of the icaA, icaB, icaC, and icaD genes among the studied isolates were as follows: 42 isolates were icaA positive (38.18%), 34 icaB positive (30.9%), 46 icaC positive (41.8%), and 50 were icaD positive (45.4%).
    Conclusion
    The high prevalence of icaA/D harboring S. aureus among the clinical isolates suggests that the risk of persistent infections in the hospital settings is considerably high.
    Keywords: Staphylococcus aureus, Methicillin-resistant Staphylococcus aureus, icaABCD
  • Haedeh Mobaiyen, Maisam Nasarollah Pour, Franak Elmi Pages 71-74
    Introduction
    The aim of this study was to characterize the chemical composition and antimicrobial activity of Trachyspermum copticum essential oil (EO).
    Methods
    The chemical composition of seed samples obtained from Mianeh city in East Azerbaijan, was assessed using gas chromatography-mass spectrometry (GC-MS). The antimicrobial activity was evaluated by disc diffusion method against methicillin-resistant Staphylococcus aureus (MRSA), other extended-spectrum beta-lactamases (ESBLs) producing, as well as Gram-negative and Gram-positive bacteria. The minimum inhibitory concentration (MIC) value of EO was assessed using agar dilution method.
    Results
    Thirteen monoterpene hydrocarbons (57.6%) and oxygenated monoterpenes (42.4%) compounds were identified in the EO, of which, 3 compounds, including thymol, m-cymene, and, γ-terpinene were the major components of the EO with quantities of 41.9, 33.53, and 20.42%, respectively. The EO showed antimicrobial activity against ten microorganisms, especially Streptococcus sanguis, S. aureus (MRSA strain), and Klebsiella pneumoniae (ESBL-producing strain), which was potentially better than tetracycline and kanamycin.
    Conclusion
    This study confirmed that EO of T. copticum has in vitro antimicrobial activity against Gram-negative and Gram-positive bacteria, which has made it an alternative antibacterial agent.
    Keywords: Phytochemicals, Trachyspermum copticum, Essential Oil
  • Hoda Pasdar, Naser Foroughifar, Bahare Hedayati Saghavaz Pages 75-79
    Introduction
    The chemistry of metal complexes derived from heterocyclic compounds has attracted considerable interest due to the broad range of pharmacological activities of such compounds. The important pathogens such as Escherichia coli, and Staphylococcus aureus are wildly caused many diseases. So antibacterial activity of Zn (Ⅱ), Ni (Ⅱ), Co (Ⅱ) and Cu (Ⅱ) chromone complexes against two kinds of bacteria was established.
    Methods
    In this study, antibacterial activity of metal complexes derived from 2-amino-7, 7-dimethyl-5-oxo-4-methylbenzen5, 6, 7, 8-tetra hydro-4H-chromone-3-carbonitrile were studied. The metal complexes were characterized by FTIR, UV-Vis and Mass spectroscopy. Antibacterial effect of these compounds was evaluated by disc diffusion and micro broth dilution methods.
    Results
    The results obtained in this study demonstrate that all the complexes have square planner geometry with the stoichiometry 1:2 (Metal: Ligand). Among the tested compounds the most effective compound was the Cu complex with MIC value of 62.5 mg/mL against E. coli and 125 mg/mL against S. aureus.
    Conclusion
    The results of these studies show that metal the metal complexes had higher antibacterial activity against species when compared to parent ligand.
    Keywords: Heterocyclic Compounds, Escherichia coli, Staphylococcus aureus