Dissemination of Acinetobacter baumannii clones with OXA-23 Carbapenemase in Colombian hospitals.

During 2005, 66 carbapenem-resistant isolates of Acinetobacter baumannii were collected from seven tertiary-care hospitals participating in a nationwide surveillance network in Colombia. The isolates were multidrug resistant and produced the carbapenemases OXA-23 and OXA-51. Forty-five belonged to four clones while 21 were unique pulsotypes.

First identification of Pseudomonas aeruginosa isolates producing a KPC-type carbapenem-hydrolyzing beta-lactamase.

In Medellin, Colombia, three Pseudomonas aeruginosa isolates with high-level carbapenem resistance (MIC>or=256 microg/ml) and an isolate of Citrobacter freundii with reduced susceptibility to imipenem produced the plasmid-mediated class A carbapenemase KPC-2. This is the first report of a KPC-type beta-lactamase identified outside of the family Enterobacteriaceae.

Effects of side-chain orientation on the 13C chemical shifts of antiparallel beta-sheet model peptides.

The dependence of the (13)C chemical shift on side-chain orientation was investigated at the density functional level for a two-strand antiparallel beta-sheet model peptide represented by the amino acid sequence Ac-(Ala)(3)-X-(Ala)(12)-NH(2) where X represents any of the 17 naturally occurring amino acids, i.e., not including alanine, glycine and proline.

[Antimicrobial resistance in gram negative bacteria isolated from intensive care units of Colombian hospitals, WHONET 2003, 2004 and 2005].

Introduction: Surveillance systems play a key role in the detection and control of bacterial resistance. It is necessary to constantly collect information from all institutions because the mechanisms of bacterial resistance can operate in different ways between countries, cities and even in hospitals in the same area. Therefore local information is important in order to learn about bacterial behaviour and design appropriate interventions for each institution.

Leishmania amazonensis infections in Oryzomys acritus and Oryzomys nitidus from Bolivia.

Three of thirteen Oryzomys acritus, Emmons and Patton 2005 (Rodentia: Muridae: Sigmodontinae) and 3 of 17 Oryzomys nitidus, Thomas 1884, collected from Noël Kempff National Park, Bolivia, from 2002 to 2005, tested positive for Leishmania (Leishmania) amazonensis or L. (L.) mexicana and negative for Leishmania (Viannia) spp.

Persistent human papillomavirus infection is associated with a generalized decrease in immune responsiveness in older women.

The development of cervical cancer and its precursors are linked to persistent infection with oncogenic types of human papillomavirus (HPV). Host immune responses seem to be determinants of risk for this disease. However, little is known about the immunologic determinants of HPV persistence.

First detection of the plasmid-mediated class A carbapenemase KPC-2 in clinical isolates of Klebsiella pneumoniae from South America.

The plasmid-mediated class A carbapenemase KPC-2 was isolated from unrelated Klebsiella pneumoniae isolates in Medellin, Colombia. These KPC enzymes are the first from South America and the second isolation outside of the United States. The expanding geographic spread of KPC carbapenemases underscores the importance of clinical recognition of these enzymes.

Retrograde rotablator in limb salvage: a new technique using an open approach.

Conventional vascular surgery and balloon angioplasty have poor results in severe and diffuse atherosclerotic disease of the infrapopliteal arteries. High-speed rotational atherectomy (Auth Rotablator) has not succeeded either, because of poor long-term patency and the non-reflow phenomenon. We report a case of limb salvage with long occlusion of the three infrapopliteal vessels.

Nitrogen-fixing sinorhizobia with Medicago laciniata constitute a novel biovar (bv. medicaginis) of S. meliloti.

Sixty-eight new rhizobial isolates were obtained from root-nodules of Medicago laciniata and from Mediterranean soils in Tunisia and France. All of them were identified as Sinorhizobium meliloti on the basis of PCR-RFLP analyses of 16S rDNA and the intergenic spacer sequence between 16S and 23S rDNAs. DNA/DNA hybridization, phenotypic characterization and 16S rRNA gene sequencing led to the conclusion that they belong the same taxon.

First detection of metallo-beta-lactamase VIM-2 in Pseudomonas aeruginosa isolates from Colombia.

Carbapenem resistance rates in Pseudomonas aeruginosa isolates in Colombia, as in many South American countries, are high for reasons that remain unclear. From our nationwide network, we describe the first detection of the metallo-beta-lactamase VIM-2 in clinical isolates of P. aeruginosa from multiple cities within Colombia.

Favorable outcome of pneumonia due to Panton-Valentine leukocidin-producing Staphylococcus aureus associated with hematogenous origin and absence of flu-like illness.

Reported here is what is believed to be the first case of community-acquired pneumonia caused by a Panton-Valentine leukocidin-producing strain of Staphylococcus aureus in Spain. Although lung infections caused by S. aureus strains carrying this powerful leukocidin gene are associated with necrotizing pneumonia and high mortality, the previously healthy 28-year-old male reported here experienced a good clinical course and recovery.

Mechanisms of resistance to beta-lactams in some common Gram-negative bacteria causing nosocomial infections.

Gram-negative bacilli remain major killers of hospitalized patients and continue to evolve new resistance mechanisms. This review describes the mechanisms of resistance to beta-lactam antibiotics from those Gram-negative pathogens most often isolated from nosocomial infections.

Laparoscopic repair for perforated peptic ulcer disease.

Background: Perforated peptic ulcer is a common abdominal disease that is treated by surgery. The development of laparoscopic surgery has changed the way to treat such abdominal surgical emergencies. The results of some clinical trials suggest that laparoscopic surgery could be a better strategy than open surgery in the correction of perforated peptic ulcer but the evidence is not strongly in favour or against this intervention.

Interface double-exchange ferromagnetism in the Mn-Zn-O system: new class of biphase magnetism.

In this Letter, we experimentally show that the room temperature ferromagnetism in the Mn-Zn-O system recently observed is associated with the coexistence of Mn(3+) and Mn(4+) via a double-exchange mechanism. The presence of the ZnO around MnO(2) modifies the kinetics of MnO(2)-->Mn(2)O(3) reduction and favors the coexistence of both Mn oxidation states. The ferromagnetic phase is associated with the interface formed at the Zn diffusion front into Mn oxide, corroborated by preparing thin film multilayers that exhibit saturation magnetization 2 orders of magnitude higher than bulk samples.

Elucidating a particulate matter deposition episode by combining scanning electron microscopy and X-ray fluorescence spectrometry.

Multielemental composition and morphology of particulate matter samples were examined to detect the presence of two potential responsible pollutant emitters at four sites impacted during a pollution episode in the City of Campana, Argentina. Coke and smoke black are the main constituents associated to the industrial plants that were considered, a priori, as responsible pollutant emitters. Wavelength dispersive X-ray fluorescence (WDXRF) was employed for the analysis of metals in samples coming from both, suspected sources and four sites.

[Use of a coronary risk score (the TIMI Risk Score) in a non-selected patient population assessed for chest pain at an emergency department].

Introduction And Objectives: Stratification algorithms for acute coronary syndrome enable the identification of high-risk patients who will benefit from more aggressive treatment. The TIMI Risk Score (TRS) has been shown to be useful in intermediate- and high-risk patients. However, little is known about its value in non-selected patients.

Evaluation of air acidity through optical sensors.

Optical sensors developed from dye-doped coatings obtained through the sol-gel method were designed and produced to evaluate air acidity. Both laboratory calibration and field test measurements in several locales of downtown Cracow, Poland, were undertaken with the aim of assessing the sensors' behavior. As a first approach, SO2 was considered as the main gaseous pollutant with acid properties capable of sensitizing the sensors under humid conditions.

Surgical options for malignant left-sided colonic obstruction.

Purpose: We evaluated the clinical results of different techniques of resection for malignant left-sided colonic obstruction.

Methods: The subjects of this prospective nonrandomized study were 63 consecutive patients who underwent surgery between 1995 and 2000 at a single institution. Patients with nonprimary colonic tumors, lesions located proximally to splenic flexure, peritonitis, perforation, or cecal necrosis were excluded.

Nanostructure and magnetic properties of the MnZnO system, a room temperature magnetic semiconductor?

The magnetic properties of the system MnZnO prepared by conventional ceramic procedures using ZnO and MnO(2) starting powders are studied and related to the nanostructure. Thermal treatment at 500 °C produces a ferromagnetic phase, although this temperature is not high enough to promote proper sintering; thus the thermally treated compact shows brittle characteristics of unreacted and poorly densified ceramic samples. Scanning electron microscopy and x-ray analysis reveal the appearance of a new phase, most probably related to the diffusion of Zn into MnO(2) oxide nanocrystals.

Reactions of excited states of phenoxazin-3-one dyes with amino acids.

The interaction with amino acids of the excited states of the N-oxide resazurin and its deoxygenation product resorufin, has been studied in aqueous solution at pH 7.5. Steady-state and time-resolved studies show that the fluorescence is quenched by amino acids.

Intra-abdominal infection in patients with abdominal trauma.

Hypothesis: Identifying patients with risk factors associated with the development of intra-abdominal infections makes possible early interventions to minimize morbidity and mortality. We sought to determine the incidence of intra-abdominal infection (organ/space surgical site infection) in patients undergoing operation because of abdominal trauma, to identify the risk factors associated with the development of this complication, and to estimate the respective magnitudes of the risk factors.

Design: We performed a prospective cohort study in patients older than 12 years who were treated surgically for penetrating or blunt abdominal trauma, with or without other associated lesions.

Flexions of the popliteal artery: dynamic angiography.

Background: Stenting of popliteal artery (PA) with self-expandable stents is a therapeutic option in selected patients with arterial disease. Fractures of these stents may occur, and they are thought to be related to development of hinge points (HPs) secondary to knee flexion. However, it remains obscure how movements of the knee affect the morphology of the PA and where HPs occur.

Prevalence and characterization of extended-spectrum beta-lactamases in Klebsiella pneumoniae and Escherichia coli isolates from Colombian hospitals.

Gram-negative pathogens harboring extended-spectrum beta-lactamases (ESBL) are widely prevalent in Latin America, but little is known about their prevalence in Colombia. A network of 8 tertiary care hospitals in Bogotá, Medellín, and Cali, Colombia, was formed in January 2002 to determine the prevalence of ESBL-producing Klebsiella pneumoniae and Escherichia coli. We characterized and established the molecular epidemiology of ESBLs from these hospitals.