---

Abstract: Background and Objective: A wide variety of opportunistic pathogens has been detected in hospital surfaces. Among these , Pseudomonas species are one of the leading causes of nosocomial infections, frequently found in hospital environments. The purpose of this study was identification of antimicrobial susceptibility of Pseudomonas spp. isolated from different Section of ShahidRajaeii hospital, Tonekabon. Material and Methods: the samples (460) from different sections of Shahid Rajaeii hospital, Tonekabon were collected between December 2010 and June 2011. The identification of the strains was performed by using biochemical tests and API20NE (Biomerieux) ,and antimicrobial susceptibility of the isolates against different antibiotics was determined by disc diffusion test. Results: of 460, 61(%13/26) strains of Pseudomonas are isolated from all the sources. The highest rate of Pseudomonas spp. is recorded in Surgery and ICU, while the lowest in Dialysis ward. Of 61 strains of Pseudomonas, 52 (85/25%) are belonged to Pseudomonas aeruginosa, six (9/83%) to Pseudomonas stutzeri, two (3/28%) to Pseudomonas putida and one (1/64%) to Pseudomonas fluorescens. Conclusion: the environments of the hospital can be the vehicles of Pseudomonas spp. therefore, both the patients and personnel should have extra attention to their personal hygiene to avoid Pseudomonas infection. Keywords: Nosocomial Infections Pseudomonas Antibiotic Susceptibility

---

Background and objectives: HIV-1 Nef and Vpr antigens have been described as suitable candidates for therapeutic HIV vaccine development. The aim of this study was to generate Nef-Vpr fusion gene construct and to clone the construct into pET-23a (+), a prokaryotic expression vector.
Methods: HIV-1 Nef and Vpr genes were PCR-amplified from the pNL4-3 plasmid using specific primers and Pfu DNA polymerase. Results of PCR amplification were visualized by electrophoresis on 0.8% agarose gel. At first, the amplified Nef fragment was cloned into NheI and BamHI restriction sites of pET-23a expression vector. Next, cloning of Vpr gene was performed into BamHI and HindIII restriction sites of the pET-23a-Nef vector. Finally, purity of the recombinant pET-23-Nef-Vpr construct was determined by NanoDrop spectrophotometry.
Results: PCR amplification of Nef and Vpr genes was confirmed by detection of ~ 620 bp and ~ 291 bp bands, respectively. Cloning of the Nef-Vpr construct into the vector was confirmed by detection of a ~ 911 bp fragment following enzymatic digestion with NheI and HindIII and sequencing.
Conclusion: The successful construction of recombinant fusion plasmid encoding a chimeric Nef-Vpr gene was performed in a prokaryotic expression vector for development of HIV-1 recombinant protein vaccine in near future.