Characterization of the enzymatic resistance to β-lactamics in enterobacteria

Detecting the resistance to CTG in severe infections-by enterobacteria guides to successful treatments. The main resistance mechanisms are the production of extended spectrum β-lactamases (BLEE), chromosomal inducible or derepressed β-lactamases Amp-C type or plasmidic Amp-C. The aim of this study was to investigate and characterize the mechanisms involved in the resistance to CTG in clinical isolations of enterobacteria, by phenotypic and genotypic methods. 64 isolations resistant to CTG were studied (K. pneumoniae, E. coli, Enterobacter spp and Proteus spp ). Antimicrobial agents sensibility and phenotypic detection of Amp-C and BLEE enzymes was performed by diffusion and dilution methods. In cefotaxime resistant E. coli and K. pneumoniae strains a possible enzymatic resistance mechanism was detected by Masuda Bioassay. The genes bla CTX-M-2 and bla PER-2 were detected by PCR. Of 64 isolations, 8 strains were presumptively producers of derepressed Amp-C and 56 were BLEE producers (with prevalence of CTX-M-2). Accompanying resistance was observed. Masuda Bioassay was negative and accompanying resistance suggests it is due an impermeability phenomenon. Our results confirm that the resistance to CTG in our strains is mainly caused by enzymes coded in plasmids so that it merit to establish epidemic control measures and to emphasize wise use of β-lactamic agents available.Fil: Castillo, Natalia Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Planta Piloto de Procesos Industriales Microbiológicos; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; ArgentinaFil: Jure, M. A.. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; ArgentinaFil: Allori, C.. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; ArgentinaFil: Castillo, M.. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; ArgentinaXXIII Jornadas Científicas de la Asociación de Biología de TucumánTucumánArgentinaAsociación de Biología de Tucumá

Bohmian Mechanics and Quantum Information

Many recent results suggest that quantum theory is about information, and that quantum theory is best understood as arising from principles concerning information and information processing. At the same time, by far the simplest version of quantum mechanics, Bohmian mechanics, is concerned, not with information but with the behavior of an objective microscopic reality given by particles and their positions. What I would like to do here is to examine whether, and to what extent, the importance of information, observation, and the like in quantum theory can be understood from a Bohmian perspective. I would like to explore the hypothesis that the idea that information plays a special role in physics naturally emerges in a Bohmian universe.Comment: 25 pages, 2 figure

Realism about the Wave Function

A century after the discovery of quantum mechanics, the meaning of quantum mechanics still remains elusive. This is largely due to the puzzling nature of the wave function, the central object in quantum mechanics. If we are realists about quantum mechanics, how should we understand the wave function? What does it represent? What is its physical meaning? Answering these questions would improve our understanding of what it means to be a realist about quantum mechanics. In this survey article, I review and compare several realist interpretations of the wave function. They fall into three categories: ontological interpretations, nomological interpretations, and the \emph{sui generis} interpretation. For simplicity, I will focus on non-relativistic quantum mechanics.Comment: Penultimate version for Philosophy Compas

On the Meaning of the String-Inspired Noncommutativity and its Implications

We propose an alternative interpretation for the meaning of noncommutativity of the string-inspired field theories and quantum mechanics. Arguments are presented to show that the noncommutativity generated in the stringy context should be assumed to be only between the particle coordinate observables, and not of the spacetime coordinates. Some implications of this fact for noncomutative field theories and quantum mechanics are discussed. In particular, a consistent interpretation is given for the wavefunction in quantum mechanics. An analysis of the noncommutative theories in the Schr\"odinger formulation is performed employing a generalized quantum Hamilton-Jacobi formalism. A formal structure for noncommutative quantum mechanics, richer than the one of noncommutative quantum field theory, comes out. Conditions for the classical and commutative limits of these theories have also been determined and applied in some examples.Comment: References, comments, and footnotes are included; some changes in section

Comprehensive study of the reactions induced by 12C on 103Rh up to 33 MeV/nucleon

Abstract Fifty-three excitation functions for the production of radioactive residues in the interaction of 12C with 103Rh have been measured from the Coulomb barrier up to 400 MeV by means of the activation technique. These excitation functions have been analyzed considering complete fusion, incomplete fusion of 8Be and α-particle fragments and, above about 200 MeV, the transfer of either one proton or one neutron from 12C to 103Rh. The emission of pre-equilibrium particles during the thermalization of the excited composite nuclei formed in all these processes and, in the case of 8Be and α incomplete fusion, also the re-emission of α-particles after a mean-field interaction or a few interactions with the target nucleons have been taken into account

Detection, isolation and characterization of Shiga toxin-producing Escherichia coli (STEC) in fresh ground beef from butcher shops in Concepción, Tucumán Province

Escherichia coli productor de toxina Shiga (STEC) es un patógeno emergente transmitido por alimentos. Existen numerosos serotipos de STEC asociados a enfermedad en humanos, entre los cuales prevalece el serotipo O157:H7. La carne molida es el principal vehículo de transmisión. En la ciudad de Concepción, provincia de Tucumán, entre setiembre y diciembre de 2004 se diagnosticaron dos casos de síndrome urémico hemolítico (SUH). El objetivo de este trabajo fue detectar, aislar y caracterizar STEC O157 y no-O157 a partir de muestras de carne molida fresca obtenidas en las bocas de expendio. Entre los meses de setiembre y diciembre de 2004 se recolectaron 53 muestras de carne molida fresca en carnicerías de la ciudad de Concepción. Para la detección, el aislamiento y la caracterización de STEC O157:H7 se utilizó la metodología USDA-FSIS 2002. Para la detección de E. coli no-O157 se utilizaron dos técnicas de PCR; para el aislamiento y la caracterización se utilizó una metodología previamente validada en una etapa intralaboratorio. Siete muestras fueron positivas para el gen stx2 , de las cuales 4 también fueron positivas para el gen rfbO157. Sin embargo, solo se aisló una cepa de E. coli O157:H7 biotipo C, portadora de los genes eae, stx2 y ehxA. El presente trabajo refleja la importancia de implementar técnicas que permitan detectar este grupo de patógenos emergentes a partir de productos cárnicos.Shiga toxin-producing Escherichia coli is an emerging foodborne pathogen. There are many STEC serotypes associated with human diseases, being the O157:H7 serotype the most prevalent. Ground beef is the main transmission vehicle. In Concepción city, Tucumán Province, between September and December 2004, two hemolytic uremic syndrome (HUS) cases were diagnosed. The main objective of this work was to detect, isolate and characterize STEC O157 and non-O157 strains in fresh ground beef. Between September and December 2004, 53 fresh ground beef samples were collected from butcher shops in Concepción city. The USDA-FSIS (2002) methodology was used for detection, isolation and characterization of STEC O157:H7. Two PCR techniques for E. coli non-O157 detection and a previous intra-laboratory validated methodology for the isolation and characterization of these strains were used. The stx2 gen was identified in seven samples and the rfbO157 gene also in four of them. However, only one E. coli O157:H7 strain, biotype C, carrying the eae, stx2 and ehxA genes, was isolated. The present study shows the importance of implementing techniques for the detection of this emerging pathogen in meat samples.Instituto de Genética Veterinari

The "Unromantic Pictures" of Quantum Theory

I am concerned with two views of quantum mechanics that John S. Bell called ``unromantic'': spontaneous wave function collapse and Bohmian mechanics. I discuss some of their merits and report about recent progress concerning extensions to quantum field theory and relativity. In the last section, I speculate about an extension of Bohmian mechanics to quantum gravity.Comment: 37 pages LaTeX, no figures; written for special volume of J. Phys. A in honor of G.C. Ghirard

Decoherence, the measurement problem, and interpretations of quantum mechanics

Environment-induced decoherence and superselection have been a subject of intensive research over the past two decades, yet their implications for the foundational problems of quantum mechanics, most notably the quantum measurement problem, have remained a matter of great controversy. This paper is intended to clarify key features of the decoherence program, including its more recent results, and to investigate their application and consequences in the context of the main interpretive approaches of quantum mechanics.Comment: 41 pages. Final published versio

Carrageenan-based hydrogels for the controlled delivery of PDGF-BB in bone tissue engineering applications

One of the major drawbacks found in most bone tissue engineering approaches developed so far consists in the lack of strategies to promote vascularisation. Some studies have addressed different issues that may enhance vascularisation in tissue engineered constructs, most of them involving the use of growth factors (GFs) that are involved in the restitution of the vascularity in a damaged zone. The use of sustained delivery systems might also play an important role in the re-establishment of angiogenesis. In this study, !-carrageenan, a naturally occurring polymer, was used to develop hydrogel beads with the ability to incorporate GFs with the purpose of establishing an effective angiogenesis mechanism. Some processing parameters were studied and their influence on the final bead properties was evaluated. Platelet derived growth factor (PDGF-BB) was selected as the angiogenic factor to incorporate in the developed beads, and the results demonstrate the achievement of an efficient encapsulation and controlled release profile matching those usually required for the development of a fully functional vascular network. In general, the obtained results demonstrate the potential of these systems for bone tissue engineering applications.This work was supported by the European NoE EXPERTISSUES (NMP3-CT-2004-500283), the European STREP HIPPOCRATES (NMP3-CT-2003-505758), and by the Portuguese Foundation for Science and Technology (FCT) through the project PTDC/FIS/68517/2006 and through the V. Espirito Santo's Ph.D. grant (SFRH/BD/39486/2007)

International Consortium for Health Outcome Measurement Set of Outcomes That Matter to People Living With Inflammatory Arthritis: Consensus From an International Working Group

© 2018, The Authors. Arthritis Care & Research published by Wiley Periodicals, Inc. on behalf of American College of Rheumatology. Objective: The implementation of value-based health care in inflammatory arthritis requires a standardized set of modifiable outcomes and risk-adjustment variables that is feasible to implement worldwide. Methods: The International Consortium for Health Outcomes Measurement (ICHOM) assembled a multidisciplinary working group that consisted of 24 experts from 6 continents, including 6 patient representatives, to develop a standard set of outcomes for inflammatory arthritis. The process followed a structured approach, using a modified Delphi process to reach consensus on the following decision areas: conditions covered by the set, outcome domains, outcome measures, and risk-adjustment variables. Consensus in areas 2 to 4 were supported by systematic literature reviews and consultation of experts. Results: The ICHOM Inflammatory Arthritis Standard Set covers patients with rheumatoid arthritis (RA), axial spondyloarthritis, psoriatic arthritis, and juvenile idiopathic arthritis (JIA). We recommend that outcomes regarding pain, fatigue, activity limitations, overall physical and mental health impact, work/school/housework ability and productivity, disease activity, and serious adverse events be collected at least annually. Validated measures for patient-reported outcomes were endorsed and linked to common reporting metrics. Age, sex at birth, education level, smoking status, comorbidities, time since diagnosis, and rheumatoid factor and anti-citrullinated protein antibody lab testing for RA and JIA should be collected as risk-adjustment variables. Conclusion: We present the ICHOM inflammatory arthritis Standard Set of outcomes, which enables health care providers to implement the value-based health care framework and compare outcomes that are important to patients with inflammatory arthritis