فهرست مطالب elnaz harifi mood

This study aimed to investigate the accessible regions of the fimH mRNA using computational prediction and dot-blot hybridization to increase the effectiveness of antisense anti-virulence therapeutics against Uropathogenic Escherichia coli.

We predicted the secondary structure of the E. coli fimH mRNA using the Sfold and Mfold Web servers and RNA structure 5.5 program. Considering the predicted secondary structure, accessible regions in mRNA of fimH were determined and oligonucleotides complementary to these regions were synthesized and hybridization activity of those oligonucleotides to the fimH Digoxigenin (DIG) labeled mRNA was assessed with dot-blot hybridization.

When searching the fimH gene in the GenBank database, two lengths for this gene was discovered in different strains of E. coli. The difference was related to the nine bases in the first part of the gene utilizing either of two translation initiation sites. Based on the bioinformatics analyses, five regions lacking obvious stable secondary structures were selected in mRNA of fimH. The result of dot-blot hybridization exhibited strongest hybridization signal between the antisense oligonucleotide number one and fimH labeled mRNA, whereas hybridization signals were not seen for the negative control.

The results obtained here demonstrate that the region contains start codon of fimH mRNA could act as the potential mRNA target site for anti-fimH antisense therapeutics. It is recommended in the future both of utilizing translation initiation sites be targeted with antisense oligomers compounds.

Since the fluoroquinolones are the broad-spectrum antibiotics, they affect both Gram-negative and Gram-positive bacteria. These antibiotics are widely prescribed by physicians. As a result, some bacteria, especially Enterobacteriaceae, have shown a resistance to this family of antibiotics. The current study aimed at detecting the frequency of qnrA, qnrB, and qnrS genes, novel plasmid-mediated quinolone-resistance genes, among extended-spectrum β-lactamases (ESBL)-positive and ESBL-negative Klebsiella pneumoniae isolates.
One hundred and thirty isolates of K. pneumoniae were collected from Imam Reza Hospital and its associated clinics from May 2011 to July 2012. The isolates were tested for ESBLs by the conventional methods. Polymerase chain reaction (PCR) was performed to amplify qnr A, B, and S.
Thirty-eight (29.3%) isolates were ciprofloxacin-resistant. Among 130 K. pneumoniae infectious isolates, 56 (43%) were capable of producing ESBL; 10.8% (n=14), 15.4% (n=20), and 20.8% (n=27) of ESBL-producing K. pneumonia were positive for qnrA, qnrS, and qnrB, respectively, and 13.8% (n=18) of the isolates harbored 2 or 3 qnr genes.
The results of the current study showed that quinolone-resistance genes were more frequent in ESBL-producing K. pneumoniae (37.5%) isolates, compared with the ESBL-negative isolates (20.89%). The prevalence of qnr genes was high in K. pneumoniae isolates, with higher frequency in ESBL-positive strains. Most of the isolates were positive for all 3 groups of qnr genes and the qnrB was the most common one.

Klebsiella pneumoniae (K. pneumoniae) causes a wide range of nosocomial and community-acquired infections. In recent decades, K. pneumoniae has been known as the agent of community-acquired primary pyogenic liver abscess. In attempts to find the causes of this disease, researchers found a new virulence gene called magA (mucoviscosity-associated gene A). The present study was performed to determine the prevalence rate of magA gene among the extended-spectrum beta lactamase (ESBL)-positive and ESBL-negative K. pneumoniae strains.

The current cross-sectional study was conducted on 130 K. pneumoniae isolates collected from patients in Imam Reza hospital and its associated clinics in Mashhad city (Iran) from May 2011 to July 2012. The presence of K. pneumoniae species was confirmed by conventional microbio­logical methods. Samples were tested for the production of ESBLs by the double disk diffusion (DDS) test. PCR was performed to detect magA gene. The hypermucoviscosity (HV) phenotype of Klebsiella isolates was char­acterized by the string test.

magA gene was detected in 11(8.5%) out of 130 isolates of K. pneu­moniae. Of 11 isolates with positive result for magA gene, three cases were HV, and 8 cases were HV- phe­notype. Of 130 K. pneu­moniae isolates, 56 isolates were ESBL-positive, and 74 isolates were ESBL-negative. The magA gene was detected in 4 out of 56 (7.14%) ESBL-positive, and 7 out of 74 (9.46%) ESBL-negative samples.

In the present study, no correlation was observed between the presence of magA gene and the production of ESBL in K. pneumoniae strains isolated from different clinical samples in Mashhad.

Escherichia coli is an important bacterial species based on incidence and associated infection severity. Some E. coli strains produce extended-spectrum beta lactamase (ESBL) and are called ESBL-producing E. coli. These strains are resistant to most classes of cephalosporin and a number of other classes of antibiotics. Plasmids carrying qnr genes have been found to transmit quinolone resistance.. The aim of this study was to determine the frequency of qnr genes in ESBL-producing and non-ESBL-producing E. coli isolated from outpatient and hospitalized patient clinical specimens from Imam Reza hospital in Mashhad, Iran.. Two hundred E. coli strains, isolated from different clinical specimens were used. ESBL-producing E. coli were detected by determining susceptibility to ceftazidime, cefotaxime, and cefpodoxime with the phenotypic confirmatory test (PCT). PCR analysis was employed to detect the qnrA, qnrB, qnrS, blaTEM, and blaSHV genes.. Eighty-six (43%) isolates were ciprofloxacin-resistant. The PCT identified 85 (42.5%) of 200 E. coli isolates as ESBL-producing. The blaTEM, blaSHV, qnrA, qnrB, and qnrS gene were found in 65 (76.47%), 23 (27%), 63 (31%), 34 (17%), and 14 (7%) isolates, respectively.. The high prevalence of quinolone resistance genes, which indicates antibiotic resistance, in the Imam Reza Hospital of Mashhad is a major concern. Hence, the antibiotics prescription policy should be revised, and infection control measures should be improved..

Extended-spectrum-B-lactamase (ESBL)-producing strains of Klebsiella Pneumonia are an important cause of many serious infections in hospitalized and nonhospitalized patients and delayed treatment of these infections in crease chance of death in patients. This study was performed to determine the prevalence of ESBL-producing K. Pneumonia and to evaluate the frequency of TEM and SHV genes among the clinical samples. One hundred and thirty isolates of K. Pneumonia were collected at Imam Reza Hospital in Mashhad (Iran) from May 2011 to July 2012. ESBL production was determined by the double disk diffusion (DDs) test. PCR method was used to detect TEM and SHV genes. Of 130 patients with K. pneumonia infection 28 were out-patients and 102 hospitalized patients. The most specimens was urine samples (n=25 in out-patients, n=39 in hospitalized patients, totally 49.2%) followed by wound samples (n=3 in out-patients, n=21 in hospitalized patients, totally 21.5%), blood samples (n=19 in hospitalized, 14.6%). The prevalence of ESBL producing K. pnemoniae was estimated 43% (n=56) including three of ESBLs positive isolates from out-patients and 53 from hospitalized patients. Of 56 ESBLs positive isolates, 44(87.54%) TEM, 39(69.64%) SHV and in 27 cases (48.21%) both TEM and SHV were detected. A high prevalence of ESBL-producing K. Pneumonia among the hospital isolates obtained of urinary followed by blood and wound samples were documented. The majority of them carried both TEM and SHV genes. Results of this study alarm for the physicians because treatment and control nosocomial infections for them were difficult.