At present, novel Coronavirus (2019-nCoV, the causative agent of COVID-19) has caused worldwide social and economic disruption. The disturbing statistics of this infection promoted us to develop an effective vaccine candidate against the COVID-19. In this study, bioinformatics approaches were employed to design and introduce a novel multi-epitope vaccine against 2019-nCoV that can potentially trigger both CD 4þ and CD 8þ T-cell immune responses and investigated its biological activities by computational tools. Three known antigenic proteins (Nucleocapsid, ORF3a, and Membrane protein, hereafter called NOM) from the virus were selected and analyzed for prediction of the potential immunogenic B and T-cell epitopes and then validated using bioinformatics tools. Based on in silico analysis, we have constructed a multi-epitope vaccine candidate (NOM) with five rich-epitopes domain including highly scored T and B-cell epitopes. After predicting and evaluating of the third structure of the protein candidate, the best 3 D predicted model was applied for docking studies with Toll-like receptor 4 (TLR4) and HLA-A Ã 11:01. In the next step, molecular dynamics (MD) simulation was used to evaluate the stability of the designed fusion protein with TLR4 and HLA-A Ã 11:01 receptors. MD studies demonstrated that the NOM-TLR4 and NOM-HLA-A Ã 11:01 docked models were stable during simulation time. In silico evaluation showed that the designed chimeric protein could simultaneously elicit humoral and cell-mediated immune responses.

Background: Multiple drug-resistant strains of Acinetobacter have become common in hospitals worldwide. The problem becomes more acute with increasing resistance to carbapenems, the last resort in the treatment of hospital acquired Acinetobacter baumannii infections. Objectives: The current study was conducted to determine the antimicrobial susceptibility patterns and prevalence of OXA-type carbapenemases, among clinical isolates of A. baumannii, in Tehran hospitals, Iran. Materials and Methods: Isolates were identified as A. baumannii by PCR with specific primers for bla OXA-51-like gene. Their susceptibilities to different antibiotics were determined using disk diffusion method. Isolates were then subjected to multiplex-PCR targeting bla oxa-51, bla oxa-24, blaoxa-23 and bla oxa-58 genes. Results: Results showed that 123 of 131 (93.89%) Acinetobacter species, possessed bla oxa-51-like gene and were identified as A.baumannii. 54.47% of isolates were resistant to amikacin, 67.47% resistant to imipenem and 84.55% resistant to meropenem.All isolates were susceptible to colistin and polymixin B. 43 of 123 A. baumannii isolates(34.95%)were MDR. These isolates were resistant to amikacin, ciprofloxacin, imipenem, cefrazidim. Among 123 isolates, 100 (81.3 %) had an acquired oxa-23like carbapenemase 10 (8.1%) possessed oxa-24-like, and 1 (0.81%) possessed oxa-58-like carbapenemase. Conclusions: The present study showed that bla OXA-23-like was the most frequent carbapenemase identified among carbapenemresistant A. baumannii isolated in Tehran hospitals. Evaluation of antibiotic resistance genes in A. baumannii, is necessary to control further dissemination of these antibiotic resistant genes.

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Our results indicate that NDM-1-producing K. pneumoniae ST 13 and ST 392 are disseminated in our region. Moreover, one of our major concerns is that these isolates may be more prevalent in the near future. Tracking and urgent intervention is necessary for control and prevention of these resistant isolates.

Background:Acinetobacter baumannii has emerged as an important nosocomial pathogen. Hospital outbreaks of extensively drug resistant (XDR) A. baumannii are a great concern.Objectives:Aims of this study were to characterize the resistance determinants and genetic relatedness of (XDR) A. baumannii isolates in hospitals in Tehran, Iran.Materials and Methods:During a three-year study, clinical isolates of A. baumannii were collected from two hospitals in Tehran, Iran. Susceptibility testing to antibiotics was performed by disk diffusion method and XDR A. baumannii isolates were identified. Genes’ encoding for carbapenemase production and integrons were identified by PCR. MICs of imipenem and meropenem were determined by agar dilution. Multiple locus variable-number tandem repeat analysis (MLVA) typing was used to determine genetic relationships of XDR isolates.Results:Using PCR for amplification of blaOXA-51, 93.9% (123.131) of isolates were identified as A. baumannii and 24.4% (30.123) were XDR. These isolates were resistant to gentamicin, ciprofloxacin, amikacin, cotrimoxazole, cefepime, cefotaxime, aztreonam and ceftazidime. Thirty percent of the isolates were resistant to tigecycline. All isolates were susceptible to colistin and polymyxin-B, while 93.3% (28.30) possessed blaOXA-23-like and 6.7% (2.30) possessed blaOXA-24-like. All isolates possessed insertion sequence (ISAba1) in the upstream region of the OXA-23-like gene. Almost 96.7% (29.30) of the isolates were positive for class I integron and 43.3% (13.30) for class II. These isolates were also positive for class I. Class III integron was not detected. MLVA typing of XDR isolates showed seven clonally complexes and 16 singletons.Conclusions:The population structure of the A. baumannii isolates in our hospitals was genetically diverse. A significant association between XDR pattern and presence of class 1 integron (P < 0.001) was found indicating that many antibiotic resistance determinants are involved in development of XDR strains.