Identification of uropathogenic Escherichia coli clonal group A (CgA) in hospitalised patients.

This study provides the first description of healthcare-associated infections with Escherichia coli clonal group A (CgA) isolates in Latin America. Isolates were typed by enterobacterial repetitive intergenic consensus-PCR, pulsed-field gel electrophoresis, E. coli phylogenetic grouping, multilocus sequence typing and fimH single nucleotide polymorphism analysis.

Characterization of Ca2+ uptake in a subcellular membrane fraction of Herpetomonas sp. promastigotes.

ATP-dependent Ca2+ uptake was studied in a subcellular fraction from Herpetomonas sp. prepared by mechanical disruption and using 45Ca2+ as a tracer. The uptake was stimulated by Ca2+ with a K0.

Screening of the mitochondrial A1555G mutation in patients with sensorineural hearing loss.

Unlabelled: The A1555G mitochondrial mutation is the main alteration associated with aminoglycoside-induced deafness.

Aim: to investigate the prevalence of the A1555G mutation in patients sensorineural hearing loss patients with and without aminoglycosides antibiotic use.

Material And Method: a study of 27 cases with deafness as the sample, and 100 neonates with normal hearing as the control group.

Predicting stability of DNA duplexes in solutions containing magnesium and monovalent cations.

Accurate predictions of DNA stability in physiological and enzyme buffers are important for the design of many biological and biochemical assays. We therefore investigated the effects of magnesium, potassium, sodium, Tris ions, and deoxynucleoside triphosphates on melting profiles of duplex DNA oligomers and collected large melting data sets. An empirical correction function was developed that predicts melting temperatures, transition enthalpies, entropies, and free energies in buffers containing magnesium and monovalent cations.

A carbapenem-susceptible Pseudomonas aeruginosa strain carrying the bla(SPM) gene.

We studied a carbapenem-susceptible Pseudomonas aeruginosa strain that does not produce carbapenemase but carries the metallo-beta-lactamase gene bla(SPM) identical in sequence to the gene of other fully carbapenem-resistant isolates. Carbapenem-susceptible isolates may be silent reservoirs of the bla(SPM) gene.

Ralstonia pickettii bloodstream infections at a Brazilian cancer institution.

We describe a series of Ralstonia pickettii bloodstream infections (BSI) that occurred in 19 oncohematologic patients admitted to a hospital for patients with cancer, in the city of Rio de Janeiro, from July 1999 to February 2006. Fifty-four R. pickettii isolates were recovered from blood and catheter-tip specimens (1-5 isolates per patient).

Multilocus sequence typing of Staphylococcus aureus isolates recovered from cows with mastitis in Brazilian dairy herds.

Staphylococcus aureus is a major pathogen associated with bovine mastitis, one of the most important infectious diseases occurring in dairy cattle herds worldwide. In the present study, S. aureus isolates recovered from cows with mastitis in dairy herds located in the south-east of Brazil were genotyped by PFGE and multilocus sequence typing (MLST).

Prevalence of AmpC and other beta-lactamases in enterobacteria at a large urban university hospital in Brazil.

Production of extended-spectrum beta-lactamases (ESBLs) has been reported in virtually all species of Enterobacteriaceae, which greatly complicates the therapy for infections caused by these organisms. However, the frequency of isolates producing AmpC beta-lactamases, especially plasmid-mediated AmpC (pAmpC), is largely unknown. These beta-lactamases confer resistance to extended-spectrum cephalosporins and aztreonam, a multidrug-resistant (MDR) profile.

A case of severe pancreatitis complicated by Raoultella planticola infection.

A 45-year-old-male presented with severe pancreatitis. Two bacterial isolates obtained from peritoneal fluid and abdominal purulent secretion were identified to the species level by 15 biochemical tests and four supplementary tests as Raoultella planticola. Identification was confirmed by rpoB gene sequencing.

BlaGES carrying Pseudomonas aeruginosa isolates from a public hospital in Rio de Janeiro, Brazil.

Previous analysis of Pseudomonas aeruginosa class-1 integrons from Rio de Janeiro, Brazil, revealed the blaGES gene in one isolate. We screened isolates of two widespread PFGE genotypes, A and B, at a public hospital in Rio, for the presence of blaGES. The gene was detected in all seven P.

Identification of clinical isolates of indole-positive and indole-negative Klebsiella spp.

Biochemical methods employed to classify bacterial species have limitations and may have contributed to the taxonomic complexity recently reported for the genus Klebsiella. The objective of the present study was to apply a simple biochemical test panel to classify a collection of human Klebsiella isolates. We found that with only three additional tests, it is possible to place most isolates in a defined species.

Pseudomonas aeruginosa epidemic strain carrying bla(SPM) metallo-beta-lactamase detected in Rio de Janeiro, Brazil.

The present study was designed to characterize beta-lactamase genes and evaluate polymerase chain reaction (PCR) typing for multidrug-resistant Pseudomonas aeruginosa pulsed-field gel electrophoresis (PFGE) genotype A isolates from Rio de Janeiro, Brazil, collected between April 1999 and March 2000 and one additional isolate collected in June 2002. As reported previously, all of the genotype A isolates produced non-characterized metallo-beta-lactamase. These isolates (22) were screened for the bla(SPM) gene by PCR and dot-blotting.

Clonal composition of Staphylococcus aureus isolates at a Brazilian university hospital: identification of international circulating lineages.

In only a few instances has the clonal composition of Staphylococcus aureus collections that include methicillin-susceptible S. aureus (MSSA) been extensively characterized. In order to investigate the clonal composition of MSSA and methicillin-resistant S.

Design of LNA probes that improve mismatch discrimination.

Locked nucleic acids (LNA) show remarkable affinity and specificity against native DNA targets. Effects of LNA modifications on mismatch discrimination were studied as a function of sequence context and identity of the mismatch using ultraviolet (UV) melting experiments. A triplet of LNA residues centered on the mismatch was generally found to have the largest discriminatory power.

Endemic extended-spectrum beta-lactamase-producing Klebsiella pneumoniae at an intensive care unit: risk factors for colonization and infection.

A prospective cohort study was undertaken to describe the epidemiology of extended-spectrum beta-lactamase-producing Klebsiella pneumoniae (ESBLKp) acquisition at an intensive care unit (ICU) in a non-outbreak setting. Surveillance for ESBLKp colonization and infection was performed in patients admitted at the ICU from January, 2000, to May, 2001. Screening for ESBLKp intestinal colonization was done by culturing rectal swab specimens at admission, 72 hr after admission and weekly until discharge or detection of ESBLKp.

Characterization of modified antisense oligonucleotides in Xenopus laevis embryos.

A wide variety of modified oligonucleotides have been tested as antisense agents. Each chemical modification produces a distinct profile of potency, toxicity, and specificity. Novel cationic phosphoramidate-modified antisense oligonucleotides have been developed recently that have unique and interesting properties.

Application of molecular techniques in the study of Staphylococcus aureus clonal evolution--a review.

Staphylococcus aureus is an important agent of healthcare-associated and community-acquired infections. A major characteristic of this microorganism is the ability to develop resistance to antimicrobial agents. Several molecular techniques have been applied for the characterization of S.

Risk factors for acquisition of multidrug-resistant Pseudomonas aeruginosa producing SPM metallo-beta-lactamase.

To evaluate risk factors for colonization or infection due to multidrug-resistant Pseudomonas aeruginosa (MDRPa) carrying the bla(SPM) gene (SPM-MRDPa) among hospitalized patients, we undertook a case control study at a 480-bed, tertiary-care university hospital. Two different case definitions were used. In the first definition, a case patient (SPM case patient) was defined as a patient who had at least one isolate of SPM-MDRPa (14 patients).

Mupirocin for controlling methicillin-resistant Staphylococcus aureus: lessons from a decade of use at a university hospital.

Background: From 1990 to 1995 at Hospital Universitário Clementino Fraga Filho, patients colonized or infected with methicillin-resistant Staphylococcus aureus (MRSA) were treated with mupirocin to eliminate MRSA carriage. In 1995, 65% of MRSA patients at this hospital had mupirocin-resistant isolates. Starting in 1996, mupirocin use was restricted to patients colonized, but not infected, with MRSA.

Ralstonia pickettii and Burkholderia cepacia complex bloodstream infections related to infusion of contaminated water for injection.

Ralstonia pickettii and Burkholderia cepacia complex isolates are causes of healthcare-associated infection related to contamination of intravenously administered products. Based on microbiological and epidemiological data and molecular typing by pulsed-field gel electrophoresis, we report the occurrence of two outbreaks of R. pickettii and B.

Identification of an imipenem-resistant Pseudomonas aeruginosa clone among patients in a hospital in Rio de Janeiro.

A total of 85 Pseudomonas aeruginosa isolates were obtained from October 1999 to April 2000 in a tertiary care hospital in Rio de Janeiro, Brazil. The imipenem susceptibility was evaluated by disk diffusion and agar dilution methods, and the clonal relationship among 67 isolates was examined by macrorestriction profile analysis following pulsed-field gel electrophoresis. Imipenem resistance was observed in 52 (61.

Genetic relatedness among extended-spectrum beta-lactamase-producing Klebsiella pneumoniae outbreak isolates associated with colonization and invasive disease in a neonatal intensive care unit.

Pulsed-field gel electrophoresis typing of 60 extended-spectrum beta-lactamase-producing Klebsiella pneumoniae (ESBLKp) isolates obtained in a neonatal intensive care unit during an outbreak indicated the dissemination of two major bacterial genotypes associated with colonization and invasive disease: one composed by aminoglycoside-resistant isolates and the other by aminoglycoside-susceptible isolates. A urease-negative phenotype was observed among aminoglycoside-resistant ESBLKp. Six pairs of isolates from gastrointestinal (GI) colonization and isolates from invasive disease that occurred 3-23 days later were shown to belong to the same genotype, reinforcing a direct association between colonization and subsequent disease.

A proton pumping pyrophosphatase in acidocalcisomes of Herpetomonas sp.

Acidocalcisomes are acidic calcium storage organelles found in several microorganisms. They are characterized by their acidic nature, high electron density, high content of polyphosphates and several cations. Electron microscopy contrast tuned images of Herpetomonas sp.