[Identification of bla-CTX-M beta-lactamase in Klebsiella pnumoniae clinical isolates by polymerase chain reaction]

The incidence of extended-spectrum beta- lactamase- producing bacteria has been increased worldwide. The most common cause of resistance to extended-Spectrum cephalosporins in Klebsiella pneumoniae is the production of extended-spectrum beta lactamases [ESBLs]. In the past decade, CTX-M enzymes have become the most prevalent ESBLs in Europe, Canada and Asia. The aim of this study was to find the prevalence of ESBL-producing K .pneumoniae and molecular detection of CTX-M group in these bacteria. In the descriptive study, 100 K. pneumoniae isolates were detected bystandard biochemical tests between April 2012 and September 2012, in Besat and Imam Reza hospitals of Tehran, Iran. Susceptibility to antimicrobial agents was tested for 10 antibiotics by the disk agar diffusion [DAD] method. Also, ESBL production was screened by combined disk diffusionas recommended by the Clinical and Laboratory Standards Institute [CLSI]. Then, Screened isolates were assayed by PCR for detection of CTX-M-1 group genes. Of 100 K. pneumonia isolates, 26 isolates produced ESBLs, and also 42 isolates were CTXM- 1 producer using PCR method. According to the differences between the results of phenotypic and genotypic tests, it seems that molecular detection of drug-resistance genes is necessary. Further investigations are needed to determine the epidemiology of ESBL producing K. pneumoniae in Iran

[Production and physicochemical evaluation of Neisseria meningitidis serogroup A outer vesicle as a vaccine candidate]

Neisseria meningitidis serogroup A Polysaccharides vaccines have been available for many years, but these vaccines have many disadvantages due to their induction of T-Cell independent responses. To overcome these problems, many researches have been focused on other parts of bacterial cell component such as OMV [Outer membrane vesicle]. In this study, OMV containing PorA were extracted and evaluated by biological and immunological methods. OMV were extracted by siadat, et al method. Physicochemical properties of extracted OMV were analyzed by electron microscopy and SDS-page. The toxicity of LPS content in OMV was assayed by LAL test. The Presence of PorA was confirmed by western blot. Antibodies synthesis after immunization by OMV was evaluated using ELISA method. The content of extracted protein was 0.1 mg/ml. Size of OMV was between 50 and 150 nanometer. SDS-PAGE showed that PorA was located in 35-40 kDa. LAL test showed that the endotoxin activity was ranged in 126EU/ml which is safe for using. The ELISA test showed that the total IgG titer was elevated after first injection. The results showed that the conformation of extracted OMV was stable, and there were no progeny determinants in OMV. Also, OMV elicited high level of specific antibodies against Neisseria meningitidis serogroup A. These results indicate that the OMV can be used as a meningococcal vaccine after further investigations