L'assedio di Corinto [Texto impreso] = El sitio de Corinto : ópera séria en tres actos para representarse en el teatro de la ciudad de Valencia el año 1834

Edición en italiano y castellanoLos libretistas están tomados de José Subirá, "Variadas versiones de libretos operísticos", p. 7

Polyhexamethylene biguanide promotes adaptive cross-resistance to gentamicin in Escherichia coli biofilms

Antimicrobial resistance is a critical public health issue that requires a thorough understanding of the factors that influence the selection and spread of antibiotic-resistant bacteria. Biocides, which are widely used in cleaning and disinfection procedures in a variety of settings, may contribute to this resistance by inducing similar defense mechanisms in bacteria against both biocides and antibiotics. However, the strategies used by bacteria to adapt and develop cross-resistance remain poorly understood, particularly within biofilms –a widespread bacterial habitat that significantly influences bacterial tolerance and adaptive strategies. Using a combination of adaptive laboratory evolution experiments, genomic and RT-qPCR analyses, and biofilm structural characterization using confocal microscopy, we investigated in this study how Escherichia coli biofilms adapted after 28 days of exposure to three biocidal active substances and the effects on cross-resistance to antibiotics. Interestingly, polyhexamethylene biguanide (PHMB) exposure led to an increase of gentamicin resistance (GenR) phenotypes in biofilms formed by most of the seven E. coli strains tested. Nevertheless, most variants that emerged under biocidal conditions did not retain the GenR phenotype after removal of antimicrobial stress, suggesting a transient adaptation (adaptive resistance). The whole genome sequencing of variants with stable GenR phenotypes revealed recurrent mutations in genes associated with cellular respiration, including cytochrome oxidase (cydA, cyoC) and ATP synthase (atpG). RT-qPCR analysis revealed an induction of gene expression associated with biofilm matrix production (especially curli synthesis), stress responses, active and passive transport and cell respiration during PHMB exposure, providing insight into potential physiological responses associated with adaptive crossresistance. In addition, confocal laser scanning microscopy (CLSM) observations demonstrated a global effect of PHMB on biofilm architectures and compositions formed by most E. coli strains, with the appearance of dense cellular clusters after a 24h-exposure. In conclusion, our results showed that the PHMB exposure stimulated the emergence of an adaptive cross-resistance to gentamicin in biofilms, likely induced through the activation of physiological responses and biofilm structural modulations altering gradients and microenvironmental conditions in the biological edifice

Depuranat project: sustainable management of wastewater in rural areas

The Urban Wastewater Directive is aiming to implement adequate treatments of collected wastewater before 31 December 2005 in small communities with a population until 2000 equivalentinhabitant. Within the framework of the DEPURANAT project, co-financed by the European Interregional Cooperation Programme (Interreg IIIB Atlantic Arc), several Natural Reclamation Systems (NRS) based upon no-conventional technologies of wastewater treatment, have been studied from different points of view in rural areas: their effectiveness for producing regenerated wastewater of acceptable quality for several reuse options and vegetal biomass for different purposes, their environmental integration or their potential of implementation. Most of these treatment plants achieved high mean removal efficiencies: TSS (73–96%); BOD5 (74–94%); COD (53–90%); E. coli (2–3 log units); Enterococci (1.5–4 log units). The environmental impact of the systems was determined using an adapted life cycle assessment methodology and the economic analysis of the systems was focused on analysing the financial indicators, empirical cost functions, and the potential market for these technologies. Furthermore, maps of potential implementation of these systems and a support tool for deciding upon the installation of conventional or NRS were designed with the aim of promoting them.Communitary Interreg III-B Atlantic Area of EuropeDEPURANAT consortiu

Food processing as a risk factor for antimicrobial resistance spread along the food chain

Documento post-printFarms and food industries rely to a large extent on the use ofbiocides as disinfectants and other antimicrobial agents andpreservatives with antimicrobial properties in order to providefood of high microbiological quality and safe for consumers.However, in the last decades it has become apparent that long-term sub-lethal exposure to these antimicrobial agents canexert a selective pressure leading to the emergence and spreadof microbial strains with a reduced susceptibility to the usedantimicrobials, which can persistently colonize food-processing environments and recurrently contaminate food. Inaddition, it may induce resistance to unrelated and clinicallyrelevant antibiotics, in a phenomenon known as cross-resistance. This review aims to provide insights on howantimicrobial resistance emergence and spread can beaffected by certain food processing activities and to discussrecent research focused on different pathways through whichbiocides and other antimicrobials could co-select for bacteriaresistant to clinically relevant antibiotics.S

A multiplex real-time PCR for differential detection and quantification of Salmonella spp., Salmonella enterica serovar Typhimurium and Enteritidis in meats

Salmonella (S.) Typhimurium and S. Enteritidis are the major causative agents of food-borne illnesses worldwide. Currently, a rapid detection system using multiplex real-time polymerase chain reaction (PCR) has been applied for other food-borne pathogens such as Escherichia coli, Staphylococcus aureus and Streptococcus spp. A multiplex real-time PCR was developed for the simultaneous detection of Salmonella spp., especially S. Typhimurium and S. Enteritidis, in beef and pork. For the specific and sensitive multiplex real-time PCR, three representative primers and probes were designed based on sequence data from Genbank. Among the three DNA extraction methods (boiling, alkaline lysis, and QIAamp DNA Mini Kit), the QIAamp DNA Mini Kit was the most sensitive in this study. The optimized multiplex real-time PCR was applied to artificially inoculated beef or pork. The detection sensitivity of the multiplex real-time PCR was increased. The specificity of the multiplex real-time PCR assay, using 128 pure-cultured bacteria including 110 Salmonella isolates and 18 non-Salmonella isolates, was 100%, 100% and 99.1% for Salmonella spp., S. Typhimurium and S. Enteritidis, respectively. The sensitivity was 100%, 100% and 91.7% for Salmonella spp., S. Typhimurium and S. Enteritidis, respectively. The multiplex real-time PCR assay developed in this study could detect up to 0.54 ± 0.09 and 0.65 ± 0.07 log10 CFU/ml for S. Typhimurium and S. Enteritidis for beef, 1.45 ± 0.21 and 1.65 ± 0.07 log10 CFU/ml for S. Typhimurium and S. Enteritidis for pork, respectively, with all conditions optimized. Our results indicated that the multiplex real-time PCR assay developed in this study could sensitively detect Salmonella spp. and specifically differentiate S. Typhimurium from S. Enteritidis in meats