فهرست مطالب

Jundishapur Journal of Microbiology - Volume:11 Issue: 7, 2018
  • Volume:11 Issue: 7, 2018
  • تاریخ انتشار: 1397/05/06
  • تعداد عناوین: 7
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  • Seyede Manizhe Heidarnejadi, Abdollah Rafiei *, Manoochehr Makvandi, Majid Pirestani, Jasem Saki, Ataallah Ghadiri Page 1
    Background
    Cryptosporidium parvum may contribute to upregulation or downregulation of host cellular genes among which type I (α, β) and type II (γ) interferons play key roles to eliminate infectious agents.
    Objectives
    The current study aimed at evaluating the expressed genes related to human type I interferon response in HT-29 cell line after exposure to C. parvum for six and 24 hours.
    Methods
    Subsequently, the overexpression and under expression of 84 human genes related to type I interferons were investigated using RT2Profiler™ PCR (polymerase chain reaction) Array.
    Results
    Four top overexpressed genes including IL10, SH2D1A, MX1, and HLA-A after six hours exposure, and 10 top overexpressed genes as IL15, DDX58, CXCL10, NMI, MYD88, STAT3, IFNAR2, IFIH1, CASP1, and TLR3 were observed after 24 hours exposure. Five underexpressed genes such as TIMP1, TYK2, IRF2, PML and IRF5 were monitored for six hours.
    Conclusions
    The current study findings revealed that the overexpressed genes IL15, TIMP1, and SH2D1A may have an important role to inhibit the invasion of C. parvum.
    Also, the overexpressed genes, namely SH2D1A, MX1, and NMI, may have antiviral properties while TIMP1 may have anticancer properties. Further, the pertinent results demonstrated that the type I interferons and the relevant genes had significant effects on stimulating innate immune system against C. parvum.
    Keywords: HT29 Cells, Type I Interferon Response, Gene Profile Expression, Cryptosporidium parvum, Iowa Strain
  • Ali Jazayeri Moghadas, Farzaneh Kalantari, Mohammad Sarfi, Soroush Shahhoseini, Shiva Mirkalantari * Page 2
    Background
    Klebsiella pneumoniae as an opportunistic pathogen can be the cause of a range of nosocomial and community - acquired infections. Many virulence factors help these bacteria overcome an immune system and cause various diseases. K1 and K2 capsular antigens, also magA, wcaG, and rmpA are well - known K. pneumoniae virulence factors. Klebsiella pneumoniae has been revealed to have the ability to acquire resistance to many antibiotics, which cause treatment failure.
    Objectives
    This study aimed at determining the prevalence of magA, wcaG, rmpA, Capsular type K1, Capsular type K2, TEM, and SHV in K. pneumoniae isolates.
    Methods
    A total of 173 non - duplicate K. pneumoniae isolates were collected from two different hospitals in Semnan, Iran, from urine specimens. Klebsiella pneumoniae was identified by conventional bacteriological tests. Disk diffusion test was performed according to the guidelines of the Clinical and Laboratory Standards Institute (CLSI). Detection of virulence factors, TEM, and SHV gene was performed by specific primers.
    Results
    Frequency of virulence factors was as follow: capsular type K2: 32.9%, rmpA: 20.2%, capsular type K1: 6.9%, and wcaG: 16.2%. Also, the SHV and TEM were observed in 46.8% and 33.5%, respectively. Antibiotics resistance rates were as follow, imipenem: 7.5%, ciprofloxacin: 16.1%, levofloxacin: 17.3%, amoxicillin - clavulanic acid: 30%, trimethoprim - sulfamethoxazole: 32.9%, cefepime: 34.1%, nitrofurantoin: 35.8%, amikacin: 36.4%, aztreonam: 39.3%, ceftazidime: 42.7%.
    Conclusions
    Frequency of some virulence factors including capsular type K2, rmpA, wcaG, and also resistant rate to imipenem, amikacin, and ceftazidime were significantly higher than similar studies. Presence of virulence factors accompanied by drug resistance should make bacteria an infectious agent and lead to treatment failure.
    Keywords: Klebsiella pneumoniae, Virulence Factors, Antibiotic Resistance
  • Parisa Badiee *, Farimah Farhodi, Mohammad Ali Ghayomi, Hadis Jafarian Page 3
    Background
    Clinical and radiological features of fungal respiratory infections are nonspecific and have overlap with other respiratory diseases. A definitive diagnosis requires laboratory identification of the causative agents, of which the most frequent ones are Candida species, Aspergillus species, and Pneumocystis jirovecii.
    Objectives
    The aim of this study was to evaluate the rate of fungi identified from the respiratory tract system of patients suffering from recurrent lung disorders (lung cancer or mycobacterial infections) by culture and real-time PCR.
    Methods
    One hundred and ninety-two bronchoalveolar lavage and sputum samples from 96 patients with clinical and radiological signs and symptoms of lung diseases were collected and cultured. The identification of fungi was made by the macroscopic and microscopic examination of the isolates and yeasts were identified by the API 20 C AUX system. Pneumocystis jirovecii was detected by the microscopic examination of the samples through immunofluorescence staining and real-time PCR.
    Results
    Fungi identification was successful in 49/96 (51%) patients. The Candida species growth was observed in the culture of 28/96 (29.2%). Aspergillus species were isolated from 7 patients (7.3%). The most frequent species identified were Candida albicans, C. glabrata, C. krusei, Aspergillus flavus, and A. fumigatus. Pneumocystis jirovecii immunofluorescence staining was positive in 23.9% of the patients with more than five cysts and 42.7% of the patients with less than five cysts. By real time-PCR, P. jirovecii was detected in 54.2% of the patients.
    Conclusions
    A high frequency of identified fungi may be present as documented infection or colonization of the airways in pulmonary diseases. The management of high risk and immunosuppressed patients requires special attention to fungi identified from them.
    Keywords: Pneumonia, Mycobacterium Infections, Pneumocystis jirovecii, Aspergillus, Candida
  • Shiva Mirkalantari, Ali Jazayeri Moghadas * Page 4
    Background
    CTX-M is the most prevalent and rapidly growing type of the extended-spectrum β-lactamase (ESBL) family and CTX-M1 is the most common type of blaCTX-M.
    Objectives
    The current study aimed at investigating the genetic diversity of CTX-M-1-producing Klebsiella pneumoniae circulating in Semnan, Iran evaluated by multilocus variable-number tandem repeat analysis (MLVA).
    Methods
    A total of 110 isolates of K. pneumoniae were collected from different clinical samples. The antibiotic suceptibility and double disk synergy test were determined according to CLSI (the clinical and laboratory standards institute) guidelines. The polymerase chain reaction (PCR) method was performed to detect CTX-M-1. The eight loci for MLVA genotyping were selected along with the primers previously described.
    Results
    Imipenem, with 84.7% susceptibility, was the most effective antibiotic against K. pneumoniae. Seventy (63.63%) isolates had ESBL positive results and 42 (60 %) of them were positive for CTX-M-1 gene. Totally, 28 MLVA genotypes were discriminated, evaluation of diversity indexes (DIs) for eight loci showed that six different alleles were the most polymorphic and the most DI was 0.807.
    Conclusions
    The findings of the current study demonstrated heterogeneity among CTX-M-1-producing K. pneumonia strains. The presence of CTX-M-1 in different MLVA types demonstrated that a certain clone is not responsible for spreading the isolates.
    Keywords: Bacterial Typing, Drug Resistance, ?, Lactamases, Klebsiella pneumoniae
  • Arman Mosavat, Saman Soleimanpour, Hadi Farsiani, Himen Salimizand, Abdollah Kebriaei, Saeid Amel Jamehdar, Mahmoud Bagheri, Seyed Abdolrahim Rezaee, Kiarash Ghazvini * Page 5
    Background
    Acinetobacter baumannii is one of the major opportunistic pathogens with increasing clinical significance, particularly in the Hospital setting.
    Objectives
    The study aimed to analyze the antibiotic resistance determinants in multidrug-resistant A. baumannii (MDRAB) isolates collected after an outbreak, with regard to the infection prevention control (IPC) interventions to eradicate the outbreak.
    Methods
    Thirty nine isolates of MDRAB were collected during six months of the study after the outbreak. Infection prevention control was successful only for the first three months after the intervention. Antimicrobial susceptibility testing and minimum inhibitory concentrations (MICs) were determined by E-test. In addition, various resistance genes and the clonal relatedness of the isolates were performed by PCR and REP-PCR.
    Results
    All isolates were MDRAB while being susceptible to colistin. The prevalence of blaADC, blaTEM, blaOXA24, blaVIM, and blaIMP was 82%, 100%, 70%, 61%, and 5%, respectively. blaOXA51, blaOXA23, and ISAba1 were detected in all isolates, but blaOXA58 was not. Moreover, ISAba1 was located upstream to blaOXA23 and blaADC in 100% and 38.4% of the isolates, respectively. The most prevalent AME was aadB (100%). Even though adeB and tetB efflux pumps were found in 100% and 95% of the isolates, respectively, tetA was not characterized. REP-PCR revealed five clusters of which, approximately 51% of the strains belonged to cluster C.
    Conclusions
    Regarding the molecular approach, the effectiveness of IPC and epidemiological context has been identified. Stringent infection-control measures are urgent to restrict the outbreak.
    Keywords: Acinetobacter baumannii, Drug Resistance, Infection Prevention, Control, Molecular Epidemiology, Minimum Inhibitory Concentration, Polymerase Chain Reaction
  • Sultan Ali, Zeeshan Nawaz *, Azeem Akhtar, Rizwan Aslam, Muhammad Asif Zahoor, Muhammad Ashraf Page 6
    Background
    Human brucellosis is a neglected and zoonotic disease also known as Malta fever or undulant fever.
    Objectives
    A cross sectional study was conducted to determine the seroprevalence of brucellosis and to access the role of risk factors associated with this disease in humans of Punjab, Pakistan.
    Methods
    A total of 250 serum samples were collected and subjected to Rose Bengal Plate Test and Enzyme Linked Immunosorbent Assay for screening of Brucella. A predesigned questionnaire was filled prior to sampling to collect data regarding socio - demographic and suspected risk factors of human brucellosis. Descriptive and bivariate statistical analysis was performed using the STATA software version 12.
    Results
    The study showed 16% seroprevalence of brucellosis. The prevalence was statistically higher in males (24%), age group of 20 to 30 years (26.92%), rural residents, (23%) and individuals with animals at home (22.50%). Among the related risk factors, exposure to animals (OR = 1.87, 95% CI: 0.9459, 3.6973) and consuming raw milk (OR = 2.36, 95% CI: 1.1713, 4.7760) were strongly associated with the disease.
    Conclusions
    Awareness programs in the rural population should be provided about the disease and its associated risk factors. Consuming unpasteurized milk and products should be avoided to control this disease.
    Keywords: Brucella, Seroprevalence, Risk Factors, Pakistan
  • Jhoan Fabricio Guaman, Isidro Favian Bayas-Morejon *, Veronica Arcos, Angelica Tigre-Leon, Araceli Lucio-Quintana, Sonia Salazar, Juan Gaibor-Chavez, Rivelino Ramon Curay Page 7
    Background
    This research addressed the topic of timely diagnosis of Helicobacter pylori that is currently a problem for public health in Ecuador and worldwide. The prevalence of the pathogen has increased in the last decade, especially due to its direct participation in gastric cancer generation.
    Objectives
    The present investigation was carried out to detect H. pylori in human stool samples by antigenic screening and culture.
    Methods
    The methodology used in this study was direct and indirect analysis of patients with H. pylori infection symptoms. Overall, 50 stool samples were collected (16 from males and 34 from females) and transferred immediately to the laboratory; patients were excluded due to causes such as contamination or insufficient amounts of sample for the analysis. From these samples, antigenic screening and culture in plates were carried out using the Brucella blood agar selective medium under controlled conditions. The two methods were analysed using the Kappa coefficient.
    Results
    After antigenic screening analysis, 25 samples (50%) were positive for H. pylori with four false positives for both genders. The culture results showed that 19 samples (38%) were positive with 32 isolates characteristic for H. pylori. After agreement analysis, the kappa index was 0.28 (discrete).
    Conclusions
    The detection rate by antigenic screening was higher than that obtained by culture, this is mainly due to the lack of viable cells and the difficulty of adapting adequate isolation techniques.
    Keywords: Helicobacter pylori, Detection, Antigenic Screening, Culture