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Jundishapur Journal of Microbiology - Volume:10 Issue: 1, Jan 2017

Jundishapur Journal of Microbiology
Volume:10 Issue: 1, Jan 2017

  • تاریخ انتشار: 1395/10/30
  • تعداد عناوین: 11
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  • Tayfur Demiray*, Mehmet Koroglu, Ahmet Ozbek, Mustafa Altindis Page 1
    Background
    Sphingomonas paucimobilis is a non-fermentative bacillus and found widely in nature. It acquires great interest in biofouling by production of biofilm. However, S. paucimobilis as a biofilm producer, is not studied in medical aspect. In this study we aimed to assess the biofilm production as a virulence factor in clinical isolates of S. paucimobilis together with patient demographics, clinical aspects, risk factors, and outcomes..
    Methods
    During 5 year-period, total numbers of 43 S. paucimobilis isolates identified in a clinical microbiology laboratory of an university hospital in Turkey. Thirty-three of the isolates, which were isolated from patients with clinically determined infection, were enrolled in this study. Patients’ data were collected retrospectively. VITEK II automated system (bioMérieux, Marcy L’Eoile, France) was used for identification and antimicrobial susceptibility testing. Christiansen tube method was used to determine biofilm formation..
    Results
    All the clinical isolates of S. paucimobilis produced biofilms. Primary bacteraemia (n = 16) was the most common clinical manifestation. Twenty-four of the patients were followed in the intensive care unit. Twenty-two patients had indwelling catheters. Malignancy (n = 11) and diabetes mellitus (n = 10) were the most common concomitant diseases. Tigecycline, carbapenems and aminoglycosides were the most susceptible antimicrobial agents. Degree of biofilm formation was correlated only with blood samples (P = 0.003) in the sample types group and a stay in the intensive care unit (P = 0.002) in the risk factors group..
    Conclusions
    Sphingomonas paucimobilis can cause serious infections, especially in immunocompromised patients with determined risk factors such as indwelling catheters and diabetes mellitus, due to the effects of multiple virulence factors, together with biofilm formation..
    Keywords: Sphingomonas paucimobilis, Biofilm, Virulence Factors, Risk Factors
  • Mohamed Amine Mekni *, Wafa Achour, Assia Ben Hassen Page 2
    Background
    An important observation during quantification experiments of Staphylococcus epidermidis biofilm is that there is a great difference in the biofilm biomass of different strains despite the same experimental conditions..
    Objectives
    This study aimed to study the genotypic background beyond differential rates of Polysaccharide Intercellular Adhesion (PIA) production in S. epidermidis biofilm forming strains..
    Methods
    A number of 126 strains were isolated from blood cultures (n = 40), catheter cultures (n = 50), and other specimens (n = 36). The strains were obtained from patients hospitalized at the bone marrow transplant center of Tunis. Biofilm micro-plate assay, hemagglutination, and susceptibility to proteinase K methods were used to assess biofilm characteristics in the studied strains. Conventional and real time PCR were used to assess genotypic background of biofilm formation..
    Results
    Using PCR method, we demonstrated that there is a significant difference in ica genes (P
    Conclusions
    Data reported here indicated that there is no specific genetic combination beyond the quantity of biofilm biomass in S. epidermidis. Biofilm biomass seemed to be controlled by RNAIII expression level. Further interest should be directed to biofilm dispersal since it seems that the key difference in biofilm biomass ability of S. epidermidis strains relates to factors regulating this stage..
    Keywords: Biofilm, Genes, Staphylococcus
  • Mahtab Bonyadi, Ehsanollah Ghaznavi Rad, Ghasem Mosayebi, Mohammad Rafiei, Neda Molaee, Hamid Abtahi * Page 3
    Background
    Helicobacter pylori infection can lead to the development of gastritis and peptic ulcer in humans. Two categories of diagnostic methods are generally used for the detection of H. pylori infection. Particularly, non-invasive methods are recognized as practical, feasible, and sensitive diagnostic tests for the detection of H. pylori infection..
    Objectives
    This study was designed with the aim to develop an assay, based on cytotoxin-associated gene A (CagA) antigen through western blotting method for the detection of H. pylori in fecal samples..
    Methods
    The antigenic region of CagA (arCagA) gene was amplified by polymerase chain reaction (PCR) method and cloned to pET32a plasmid. Isopropyl β-D-1-thiogalactopyranoside (IPTG) was used to induce gene expression, and Escherichia coli BL21 (DE3) pLysS was transformed into pET32a-arCagA. Afterwards, the recombinant protein was purified by Ni-NTA resin. The rats were immunized by the purified arCagA protein for the production of antibodies. For the detection of H. pylori infection, stool samples from 80 patients were evaluated, using Western blot analysis and rat anti-arCagA antibody. The antigenic recombinant CagA region was expressed in E. coli, and CagA protein was produced and purified. Rat anti-CagA antibody was produced after immunization with the recombinant antigenic protein..
    Results
    We investigated CagA protein, using the immunoblotting method in stool samples, which were already identified as positive by the application of a commercial kit. The developed test showed sensitivity of 87% and specificity of 90% in the patients..
    Conclusions
    Based on the findings, application of recombinant arCagA antigen for the detection of H. pylori infection is a simple, rapid, and brief non-invasive method. Therefore, it can be suggested as an appropriate antigen for H. pylori detection kits..
    Keywords: CagA Protein, Helicobacter pylori, Immunoblotting, Recombinant Protein
  • Farah Bokharaei Salim, Mostafa Salehi Vaziri, Farzin Sadeghi, Khadijeh Khanaliha, Maryam Esghaei, Seyed Hamidreza Monavari, Seyed Moayed Alavian, Shahin Fakhim, Hossein Keyvani * Page 4
    Background
    The hepatitis C virus (HCV) infection is one of the major causes of progressive liver diseases worldwide. Despite the new treatments for HCV infection, antiviral therapy with a combination of pegylated interferon-α 2a plus ribavirin (Peg-IFNα-2a/RBV) is still used in developing countries..
    Objectives
    The aim of the current study was to determine the relationship between rs12979860 polymorphism in the interleukin 28B gene (IL28B) and response to Peg-IFNα-2a/RBV combination therapy in Azerbaijani patients with chronic HCV infection..
    Methods
    A total of 72 Azerbaijani patients with established chronic HCV-1b took part in this cross-sectional study between January 2010 and September 2015. Genomic DNA was extracted from peripheral blood mononuclear cells (PBMCs) of the patients and the rs12979860 single nucleotide polymorphism was diagnosed by polymerase chain reaction-restriction fragment length polymorphism assay (PCR-RFLP)..
    Results
    The mean age of the patients was 36.9 ± 12.4 (range of 27 - 57 years) and 42 (58.3%) out of 72 were male. Concerning the IL28B polymorphism in rs12979860, the results indicated the presence of CC, CT, and TT genotypes in 24 (33.3%), 42 (58.3%), and 6 (8.3%) patients, respectively. There was a significant association between IL28B genotypes and response to HCV combination therapy with peg-IFNα-2a/RBV (P = 0.001)..
    Conclusions
    The results of this study indicate that the rs12979860 CC genotype of IL28B was associated with a response to Peg-IFNα-2a/RBV combination therapy in Azerbaijani patients with HCV-1b infection. Therefore, host genetics may be useful in predicting the response to hepatitis C treatment..
    Keywords: Hepatitis C Virus_Interferon_Ribavirin_IL28B Polymorphisms
  • Mojtaba Nikbakht, Mohammad Ahangarzadeh Rezaee*, Alka Hasani, Mohammad Reza Nahaei, Javid Sadeghi, Sirus Jedari Seifi Page 5
    Background
    Resistance to macrolide, lincosamide, and streptogramin B (MLSB) antibiotics is mediated by erm and msrA genes in Staphylococcus aureus. The expression of these genes can lead to three phenotypes, namely constitutive resistance (cMLSB), inducible resistance (iMLSB), which are resistant to macrolide, lincosamide, and streptogramin B antibiotics, and MSB phenotype, which is resistant only to macrolide and streptogramin B. Inducible clindamycin resistance is an important concern because it is not detected in routine laboratory tests..
    Objectives
    The aim of this study was to determine the frequency of MLSB phenotypes and genotypes among 215 clinical isolates of S. aureus and then, examine their resistance to antibacterial agents, which is recommended for methicillin-resistant S. aureus (MRSA) isolates..
    Methods
    Two hundred and fifteen non-repetitive clinical isolates of S. aureus were collected. Resistance to antibacterial agents was determined by disk diffusion and E-test methods. Susceptibility to clindamycin and erythromycin was tested by D-test. All isolates were screened by PCR for the presence of nucA, mecA, ermA, ermB, ermC, and msrA genes..
    Results
    The prevalence of iMLSB, cMLSB and MSB phenotypes among all the isolates was determined as 10.69%, 34.42%, and 0%, respectively. In our study, iMLSB was prevalent more in methicillin susceptible S. aureus (MSSA) (11.71%) than MRSA (9.19%) isolates (P = 0.557). In contrast, the rate of cMLSB was significantly higher in MRSA (79.31%) than MSSA (3.90%) isolates (P = 0.000). No MSB phenotype was detected in our study. The most prevalent genes were ermC and ermA with 39% and 21.5% frequencies, respectively. Six isolates showed D phenotype, while the PCR results of erm genes were negative. All 215 isolates of S. aureus were negative for the presence of ermB and msrA genes..
    Conclusions
    The rate of iMLSB in S. aureus isolates is relatively high in the Northwest Iran. Since isolates with inducible resistance may mutate and change to constitutive resistance, to prevent clinical treatment failure, D-test should be performed along with routine antibiotic susceptibility tests. In this study, ermC gene was the predominant genetic determinant for the expression of MLSB resistance. This predominance is probably due to the spread of distinctive clones (which carry ermC gene) in our region..
    Keywords: Methicillin-Resistant, Clindamycin, Iran, Staphylococcus aureus
  • Mohammad Sadegh Damavandi, Maryam Safarpour Dehkordi, Alireza Dehghan, Fatemeh Heibati, Roohollah Taghaddosi, Abolfazl Gholipour* Page 6
    Background
    The wide application of antibiotics and antiseptics for patient therapy and medical equipment and surfaces disinfection has resulted in the emergence of resistant microorganisms. Staphylococcus aureus and coagulase-negative Staphylococci (CoNS) are found as a part of the normal resident flora in human so that up to two-thirds of the healthy populations are permanently or transiently colonized by S. aureus and CoNS. Chlorhexidine is an antiseptic agent particularly effective against Gram-positive bacteria. It is widely used for hygienic hand wash to prevent transmission of Staphylococci nosocomial infections. The plasmid-borne qacA/B, qacC, and smr genes confer resistance to cationic antiseptic agents in S. aureus and CoNS..
    Objectives
    The objective of the current study was to characterize the antibiotic resistance and susceptibility to quaternary ammonium compounds (QACs) in methicillin-sensitive S. aureus (MSSA), methicillin-resistant S. aureus (MRSA), methicillin-sensitive coagulase-negative staphylococci (MSCoNS), and methicillin-resistant coagulase-negative Staphylococci (MRCoNS)..
    Methods
    In this study, the antibiotic susceptibility and resistance to Chlorhexidine in 120 Staphylococcal strains were evaluated by disc diffusion and Minimum inhibitory concentration (MIC) of Chlorhexidine gluconate (CHG) methods, respectively. The MICs of CHG were determined in triplicate by broth micro-dilution, and the presence of mecA, qacA/B, qacC, and smr genes was examined by PCR assay..
    Results
    Of total 60 S. aureus isolates, 51 (85%) were MRSA, and of 60 CoNS, 7 (11.66%) were MRCoNS. The results showed that the MIC of Chlorhexidine for all 120 isolates was 1-16 μg/mL. 15 (12.5%) isolates carried qacA/B gene, 26 (21.7%) carried qacC gene, and 38 (31.7%) carried smr gene..
    Conclusions
    Maintenance of MRSA isolates in the attendance of low amounts of antiseptics could result in the decreased susceptibility to antiseptics..
    Keywords: Quaternary Ammonium Compound, Minimum Inhibitory Concentration, Methicillin-Resistant Staphylococcus aureus
  • Bahador Sarkari *, Kambiz Yaghoobi, Majid Mansouri, Qasem Asgari, Samaneh Abdolahi Khabisi Page 7
    Background
    Toxoplasma gondii is a cosmopolitan protozoan, which infects the human body and many warm-blooded animals including wild boars. Wild boars have an important role in maintenance and transmission of T. gondii and may pose a potential risk to humans and wildlife health..
    Objectives
    The current study was conducted to find out the seroprevalence and genotypes of T. gondii in wild boars in southwest of Iran..
    Methods
    Twenty five adult wild boars were hunted, in 2013. Blood and tissue samples (muscle, tongue, liver, and brain) were collected from each animal. Blood samples were assessed for antibodies against T. gondii by the modified agglutination test. DNA was extracted from the tissues and PCR-amplified, targeting a 529 bp DNA fragment of T. gondii. The PCR products were purified and sequenced..
    Results
    Anti-T. gondii antibodies were detected in sera of 4 out of the 25 (16%) wild boars. There was no gender or age-related differences in seroprevalence of T. gondii in the studied animals. PCR detected the 529 bp band of T. gondii in brain samples of 5 out of 25 (20%) of animals. Molecular evaluation confirmed the presence of type III (4 cases) and type I (1 case) of T. gondii in the studied wild boars..
    Conclusions
    Findings of the study demonstrated that the T. gondii infection is common in wild boars in southwest Iran and could represent a significant health risk for animals, hunters, and local residents who may consume wild boar meat..
    Keywords: Seroprevalence, Genotypes, Wild Boars, Iran, Toxoplasma gondii
  • Roohollah Taghaddosi, Abolfazl Gholipour*, Marzieh Zeraatpisheh, Maryam Safarpour Dehkordi, Davood Darban Sarokhalil, Fatemeh Heibati Goujani Page 8
    Background
    Methicillin-resistant Staphylococcus aureus (MRSA) remains a significant public health problem and treatment challenge..
    Objectives
    This study was conducted to determine the frequency, molecular types, and drug resistance of S. aureus isolated from nasal carriers in two teaching hospitals (Hajar and Kashani) in Shahrekord, southwestern Iran..
    Methods
    In this cross-sectional study, 262 nasal specimens were obtained from healthcare staff. The disk-diffusion method was used to detect MRSA. Nine antibiotic disks were used to determine the antibiotic susceptibility pattern. Staphylococcal cassette chromosome mec (SCCmec) types were identified by the multiplex polymerase chain reaction (PCR). The data analysis was performed using Fisher’s exact test with SPSS software..
    Results
    Forty-eight (18.8%) specimens were identified as S. aureus, of which 30 (11.45%) specimens were methicillin resistant. The nasal colonization rate of the MRSA isolates was not associated with age or gender (P > 0.05). The highest resistance (33%) recorded was to rifampin, and all the isolates were susceptible to quinupristin-dalfopristin, vancomycin, and linezolid. The SCCmec results showed that 16.7%, 6.7%, 20%, and 56.6% of MRSA isolates were types I, II, III, and IV, respectively..
    Conclusions
    Nasal isolates of MRSA were prevalent among hospital staff. The highest level of resistance was to rifampin, and all the isolates were susceptible to quinupristin-dalfopristin, vancomycin, and linezolid. SCCmec type 4 was the most frequent MRSA isolate..
    Keywords: Methicillin-Resistant, Molecular Typing, Drug Resistance, Staphylococcus aureus
  • Fatemeh Daneshvar, Mohammadreza Haghshenas*, Fereshteh Majleci, Abbas Rahimi Page 9
    Background
    Cervical cancer is a leading cause of mortality in women. Infection with high-risk human papillomavirus (HPV) is recognized as an important etiological factor for the development of cervical cancer. On the other hand, cervical cancer screening can detect abnormal cervical cells and diagnose cervical cancer in the early stages..
    Objectives
    This study was performed to determine and analyse the distribution of HPV genotypes in normal cervical tissues, using polymerase chain reaction in Mazandaran province in North of Iran..
    Methods
    This cross-sectional study was performed during 2012 - 2015. Tissue samples from the cervix were collected from 450 women, referring to a healthcare centre in Mazandaran province, Iran. Pap smear was used to monitor any abnormalities or unusual findings. Also, GP5 / GP6 primers were applied for the detection of HPV DNA in the specimens. Afterwards, positive samples were selected to perform high-risk HPV genotyping, using the HPV HCR DNA genotyping kit..
    Results
    In this study, 431 (95.78%) samples were found to be normal on the Pap smear test, while 19 (4.22%) samples were abnormal. We found that the rate of positive HPV DNA was 10.22% in the tissue cervix samples. Human papillomavirus DNA was detected in 8.12% (35 of 431) of the normal tissues and 57.89% (11 of 19) of the abnormal tissues. From the 46 HPV DNA positive samples, 19 (41.30%) were HPV16, 9 (19.57%) of which were HPV18 and 1 (2.17%) was HPV45. In this study, the highest prevalence of HPV DNA was found in women within the age range of 20-24 years, which constitutes 20 (28.17%) of the HPV DNA positive samples..
    Conclusions
    Cervical cancer screening, comprising of both Pap test and HPV testing, is an essential part of the routine health care for women as it can facilitate the detection of abnormal cervical cells. HPV infection can produce abnormal Pap test results; also, certain types of HPV are associated with cancer. Therefore, it is important to diagnose abnormal cervical tissues before the development of cervical cancer..
    Keywords: Cervical Cancer, Pap Smear Test, HPV Genotyping, High-Risk HPV
  • Somayeh Mohammadi, Babak Vazirianzadeh, Reza Fotouhi, Ardakani, Elnaz Alaee Novin, Aref Amirkhani, Javad Samii, Ahmad Reza Esmaeili Rastaghi, Parviz Parvizi * Page 10
    Background
    Zoonotic cutaneous leishmaniasis (ZCL) is increasing in many parts of the world including Iran. Rodents are the most important reservoirs of Leishmania parasites in many remote areas of ZCL. Identification and molecular characterization of Leishmania parasites in reservoir hosts (rodents and dogs), potential vectors (sandflies), and suspected patients in leishmaniasis foci should be clarified for different controlling measurements and treatments..
    Objectives
    This study aimed to determine the main reservoir hosts of ZCL in Khuzestan province bordering Iran and Iraq..
    Methods
    Rodents were captured and identified using morphological and molecular techniques. Leishmania species were sampled from both ears of rodents and DNA was extracted. Leishmania detection was based on PCR and sequencing of ITS-rDNA of infected rodents. Phylogenetic analyses were conducted to understand the relationship, homology, and haplotype variations among Leishmania major parasites and identify the causative agents of leishmaniasis in the area. The maximum likelihood and neighbor-Joining with alternative Kimura 2-Parameter models were employed for phylogenetic analyses..
    Results
    Leishmania major was firmly recognized by conducting molecular analysis on 121 captured rodents, from which 45 samples unequivocally were identified as Tatera indica. Leishmania parasites obtained from T. indica were sequenced to analyze genetic polymorphism and/or similarity using ITS-rDNA genotype. Phylogenies revealed that one common haplotype of L. major (GenBank accession no. EF413075) was the most haplotype variant dominated among seven infected T. indica..
    Conclusions
    The widespread distribution of L. major parasites in human suggests not only T. indica was the main reservoir but also other rodents and mammalian hosts might be the reservoir hosts of ZCL in the region. Molecular and phylogenetic analyses confirmed the strength of haplotype variation maintaining the circulation of Leishmania species in their reservoir hosts..
    Keywords: Leishmania major, Tatera indica, Zoonotic Cutaneous Leishmaniasis, Phylogenetic Analyses, ITS-rDNA, Iran
  • Mostafa Salehi Vaziri, Shokrollah Salmanzadeh, Vahid Baniasadi, Tahmineh Jalali, Tahereh Mohammadi, Sanam Azad Manjiri, Yasaman Jamshidi, Sahar Khakifirouz, Mehdi Fazlalipour * Page 11
    Introduction
    Crimean-Congo hemorrhagic fever (CCHF) is an acute viral zoonotic disease, which is endemic in vast geographic areas including the Middle East. The causative agent, Crimean-Congo hemorrhagic fever virus (CCHFV), is a Nairovirus, which is mainly transmitted to human from infected hard ticks and viremic livestock..
    Case Presentation
    In April 2016, an outbreak of CCHF occurred in Khuzestan province, Iran, because of slaughtering a tick-infested calf and manipulation of its meat..
    Discussion
    Given that viremic livestock are the main source of CCHF outbreaks in Iran, limitation of the livestock smuggling and unhealthy slaughtering is of great importance in the prevention of CCHF in endemic regions..
    Keywords: Crimean-Congo Hemorrhagic Fever, Disease Outbreaks, Iran