54 research outputs found

    Hacienda catedralicia y promoción artística en la Catedral de Mallorca (1573-1604)

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    La relación directa entre las finanzas, la economía y la hacienda catedralicia con la promoción artística de la Catedral de Palma, en tiempos del obispo valenciano Juan Vic y Manrique de Lara (1573-1604), se refleja en fuentes documentales diversas conservadas en el Archivo Capitular de Mallorca (ACM). Mensa capitular, libros de sacristía, clavaria, cofradías, cabreo de limosnas, libros de aniversarios y distribuciones de plomos; nos han permitido exhumar nuevas noticias relacionadas con la decencia y decoro en el templo, especialmente, pintores, plateros, escultores y maestros de obras, estos últimos dirigidos por el canónigo obrero u obrero mayor. Iniciamos nuestro recorrido a través del testimonio escrito del médico al servicio del obispo, Juan Binimelis en la obra Historia General del Reino de Mallorca (1593-1595), que nos servirá de punto de partida para constatar las sinergias de los equipos de gestión diocesana y catedralicia al servicio del arte.

    C9orf72 expansion within astrocytes reduces metabolic flexibility in amyotrophic lateral sclerosis

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    It is important to understand how the disease process affects the metabolic pathways in amyotrophic lateral sclerosis and whether these pathways can be manipulated to ameliorate disease progression. To analyse the basis of the metabolic defect in amyotrophic lateral sclerosis we used a phenotypic metabolic profiling approach. Using fibroblasts and reprogrammed induced astrocytes from C9orf72 and sporadic amyotrophic lateral sclerosis cases we measured the production rate of reduced nicotinamide adenine dinucleotides (NADH) from 91 potential energy substrates simultaneously. Our screening approach identified that C9orf72 and sporadic amyotrophic lateral sclerosis induced astrocytes have distinct metabolic profiles compared to controls and displayed a loss of metabolic flexibility that was not observed in fibroblast models. This loss of metabolic flexibility, involving defects in adenosine, fructose and glycogen metabolism, as well as disruptions in the membrane transport of mitochondrial specific energy substrates, contributed to increased starvation induced toxicity in C9orf72 induced astrocytes. A reduction in glycogen metabolism was attributed to loss of glycogen phosphorylase and phosphoglucomutase at the protein level in both C9orf72 induced astrocytes and induced neurons. In addition, we found alterations in the levels of fructose metabolism enzymes and a reduction in the methylglyoxal removal enzyme GLO1 in both C9orf72 and sporadic models of disease. Our data show that metabolic flexibility is important in the CNS in times of bioenergetic stress

    Retrospective evaluation of whole exome and genome mutation calls in 746 cancer samples

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    Funder: NCI U24CA211006Abstract: The Cancer Genome Atlas (TCGA) and International Cancer Genome Consortium (ICGC) curated consensus somatic mutation calls using whole exome sequencing (WES) and whole genome sequencing (WGS), respectively. Here, as part of the ICGC/TCGA Pan-Cancer Analysis of Whole Genomes (PCAWG) Consortium, which aggregated whole genome sequencing data from 2,658 cancers across 38 tumour types, we compare WES and WGS side-by-side from 746 TCGA samples, finding that ~80% of mutations overlap in covered exonic regions. We estimate that low variant allele fraction (VAF < 15%) and clonal heterogeneity contribute up to 68% of private WGS mutations and 71% of private WES mutations. We observe that ~30% of private WGS mutations trace to mutations identified by a single variant caller in WES consensus efforts. WGS captures both ~50% more variation in exonic regions and un-observed mutations in loci with variable GC-content. Together, our analysis highlights technological divergences between two reproducible somatic variant detection efforts

    WLAN PERFORMANCE ANALYSIS FOR INDOOR ENVIRONMENTS ANÁLISIS DE LAS PRESTACIONES DE WLAN'S EN ENTORNOS DE INTERIOR ANÀLISIS DE LES PRESTACIONS DE WLAN'S A ENTORNS D' INTERIOR

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    The thesis is dedicated to the analysis of cryptographic algorithms and protocols with respect to their applicability for hardware implementation in different environments and under different constraints and optimization goals (high-throughput vs. low power). Therefore, selected algorithms will be implemented and evaluated in Hardware (FPGA, GPU) and their performance will be compared to the existing Open Source software solution. The work shall follow scientific standards and the developed code will be released under an Open Source license on the project site. AIT willStudies report that in the next years there will be a high increase in the number of mobile devices, the overall data traffic generated by mobile devices, and a migration from larger cells towards Wireless Local Area Networks (WLAN) and smaller cells (picocells and femtocells). There is also a large amount of data that is estimated to be offloaded to Wi-Fi and small cells. Due to this estimated growth in the mobile data traffic over wireless environment; several companies are investing and focusing resources in improving their services mainly related with WLAN’s. The concerns of the industry are focused on examining the performance of WLAN’s, especially indoors, and finding ways to understand more about actual User Experience (UX) in real scenarios. These ambitions require the combination of theory with practice. This thesis is mainly focused on supporting these performance estimations. Trying to help on this purpose, a Graphical User Interface (GUI) is developed for simulating and analysing certain metrics of WLAN´s in indoor environments, such as coverage and data rate. The tool not only combines several different advanced concepts relating to indoor propagation, penetration loss, layout modelling, interference modelling, and different WLAN standards; but presents them in a simple and easy-to-understand interface to the final user. The performance metrics are represented quantitatively and as accurately as possible. When the tool is run with appropriate input values, it is able to provide results such as the Signal Strength, Signal to Noise Ratio (SNR), Signal to Interference Ratio (SIR) and maximum achievable Data Rate; this allows the service providers to estimate the maximum performance of their own systems and also to validate theoretical results by simulation. This tool is the first approach to a much more complex problem that is to fully model and simulate a full WLAN system; that is why its scalability allows future improvements.Estudios muestran que en los próximos años va a haber un gran incremento en el número de dispositivos móviles, de la media de tráfico generado por todos los dispositivos móviles, y una migración desde macroceldas a Redes Wireless de Área Local (WLAN) y microceldas (picoceldas y femtoceldas). También se estima un gran incremento en la cantidad de estos datos que serán descargados a través de Wi-Fi o microceldas. Debido a este crecimiento estimado en el tráfico de los dispositivos móviles en el entorno inalámbrico, grandes compañías están invirtiendo y centrando sus recursos en las WLAN’s. Los intereses de la industria se centran en examinar las prestaciones de las WLAN’s, especialmente en entornos de interior, y encontrar medios para entender más acerca de la experiencia de usuario (UX) en situaciones reales. Estas ambiciones requieren la combinación de conocimiento tanto teórico como práctico. Esta tesis se centra principalmente en apoyar la estimación de prestaciones. Con esta finalidad, se desarrolla una Interfaz Gráfica de Usuario (GUI) para simular y analizar ciertas métricas de las WLAN’s en entornos de interior, tales como la cobertura o el data rate. La herramienta no solo combina diferentes conceptos avanzados relacionados con la propagación en entornos de interior, pérdidas de propagación, modelado de pisos, modelado de interferencias o diferentes estándares de WLAN; pero a la vez los presenta de manera simple y entendible en una interfaz para el usuario final. Las métricas analizadas se representan cuantitativamente y con la mayor precisión posible. Cuando se ejecuta la herramienta con los valores introducidos correctos, permite obtener valores como la Signal Strength, la SNR, SIR o máximo Data Rate disponible; ésto permite a los proveedores de servicio estimar las prestaciones máximas de sus sistemas y además validar resultados teóricos mediante simulación. La herramienta diseñada es una primera aproximación a un problema mucho más complejo como es el modelado y la simulación íntegra de un sistema WLAN; para ello ha sido incorporada escalabilidad, permitiendo futuras mejoras.Estudis mostren que als pròxims anys hi haurà un gran increment al nombre de dispositius móbils, de la mitjana de tràfic generat per tots els dispositius móbils i una migració de macrocel.les a xarxes inalàmbriques de Àrea Local (WLAN) i microcel.les (picocel.les I femtocel.les). També s’estima un gran augment en la quantitat d’aquestes dades que ser’an descarregats per mitjà de Wi-Fi o microcel.les. Degut a aquest creixement estimat al tràfic dels dispositius móbils a entorns inalàmbrics, grans companyies estan invertint i centrant els seus recursos a les WLAN’s. Els interessos de la industria estan centrades en examinar les prestacions de las WLAN’s, especialment a entorns d’interior, i trovar mitjans per entendre millor la experiència d’usuari (UX) a situacions reals. Aquestes ambicions requereixen la combinació de coneixements tant teòrics com pràctics. Aquesta tesis està centrada en la estimació de prestacions. Amb aquest objectiu, una Interfície Gràfica d’Usuari (GUI) es desenvolupada per simular i analitzar diferents mètriques de les WLAN’s a entorns d’interior, tals com la cobertura o el data rate. Aquesta eina no només combina diferents coneixements avançats com la propagació en entorns d’interior, pèrdues de propagació, modelat de pisos, modelat de interferències o diferents estàndards de WLAN; sino que els combina i els presenta al usuari final a una interfície senzilla. Les métriques analitzades son representades quantitativament i amb la millor precissió possible. Quan l’eina es executada amb els valor introduits correctament, permeteix obtener valors com la Signal Strength, la SNR, SIR o la màxima Data Rate disponible; això permeteix als proveidors de serveis estimar les prestacions màximes dels seus sistemes i validar resultats teòrics emprant simulacions. L’eina dissenyada es una primera aproximació a un problema molt més complexe com es el modelat i la simulació completa de sistemes WLAN; per aiò incorpora escalabilitat permetent futures millores

    WLAN PERFORMANCE ANALYSIS FOR INDOOR ENVIRONMENTS ANÁLISIS DE LAS PRESTACIONES DE WLAN'S EN ENTORNOS DE INTERIOR ANÀLISIS DE LES PRESTACIONS DE WLAN'S A ENTORNS D' INTERIOR

    No full text
    The thesis is dedicated to the analysis of cryptographic algorithms and protocols with respect to their applicability for hardware implementation in different environments and under different constraints and optimization goals (high-throughput vs. low power). Therefore, selected algorithms will be implemented and evaluated in Hardware (FPGA, GPU) and their performance will be compared to the existing Open Source software solution. The work shall follow scientific standards and the developed code will be released under an Open Source license on the project site. AIT willStudies report that in the next years there will be a high increase in the number of mobile devices, the overall data traffic generated by mobile devices, and a migration from larger cells towards Wireless Local Area Networks (WLAN) and smaller cells (picocells and femtocells). There is also a large amount of data that is estimated to be offloaded to Wi-Fi and small cells. Due to this estimated growth in the mobile data traffic over wireless environment; several companies are investing and focusing resources in improving their services mainly related with WLAN’s. The concerns of the industry are focused on examining the performance of WLAN’s, especially indoors, and finding ways to understand more about actual User Experience (UX) in real scenarios. These ambitions require the combination of theory with practice. This thesis is mainly focused on supporting these performance estimations. Trying to help on this purpose, a Graphical User Interface (GUI) is developed for simulating and analysing certain metrics of WLAN´s in indoor environments, such as coverage and data rate. The tool not only combines several different advanced concepts relating to indoor propagation, penetration loss, layout modelling, interference modelling, and different WLAN standards; but presents them in a simple and easy-to-understand interface to the final user. The performance metrics are represented quantitatively and as accurately as possible. When the tool is run with appropriate input values, it is able to provide results such as the Signal Strength, Signal to Noise Ratio (SNR), Signal to Interference Ratio (SIR) and maximum achievable Data Rate; this allows the service providers to estimate the maximum performance of their own systems and also to validate theoretical results by simulation. This tool is the first approach to a much more complex problem that is to fully model and simulate a full WLAN system; that is why its scalability allows future improvements.Estudios muestran que en los próximos años va a haber un gran incremento en el número de dispositivos móviles, de la media de tráfico generado por todos los dispositivos móviles, y una migración desde macroceldas a Redes Wireless de Área Local (WLAN) y microceldas (picoceldas y femtoceldas). También se estima un gran incremento en la cantidad de estos datos que serán descargados a través de Wi-Fi o microceldas. Debido a este crecimiento estimado en el tráfico de los dispositivos móviles en el entorno inalámbrico, grandes compañías están invirtiendo y centrando sus recursos en las WLAN’s. Los intereses de la industria se centran en examinar las prestaciones de las WLAN’s, especialmente en entornos de interior, y encontrar medios para entender más acerca de la experiencia de usuario (UX) en situaciones reales. Estas ambiciones requieren la combinación de conocimiento tanto teórico como práctico. Esta tesis se centra principalmente en apoyar la estimación de prestaciones. Con esta finalidad, se desarrolla una Interfaz Gráfica de Usuario (GUI) para simular y analizar ciertas métricas de las WLAN’s en entornos de interior, tales como la cobertura o el data rate. La herramienta no solo combina diferentes conceptos avanzados relacionados con la propagación en entornos de interior, pérdidas de propagación, modelado de pisos, modelado de interferencias o diferentes estándares de WLAN; pero a la vez los presenta de manera simple y entendible en una interfaz para el usuario final. Las métricas analizadas se representan cuantitativamente y con la mayor precisión posible. Cuando se ejecuta la herramienta con los valores introducidos correctos, permite obtener valores como la Signal Strength, la SNR, SIR o máximo Data Rate disponible; ésto permite a los proveedores de servicio estimar las prestaciones máximas de sus sistemas y además validar resultados teóricos mediante simulación. La herramienta diseñada es una primera aproximación a un problema mucho más complejo como es el modelado y la simulación íntegra de un sistema WLAN; para ello ha sido incorporada escalabilidad, permitiendo futuras mejoras.Estudis mostren que als pròxims anys hi haurà un gran increment al nombre de dispositius móbils, de la mitjana de tràfic generat per tots els dispositius móbils i una migració de macrocel.les a xarxes inalàmbriques de Àrea Local (WLAN) i microcel.les (picocel.les I femtocel.les). També s’estima un gran augment en la quantitat d’aquestes dades que ser’an descarregats per mitjà de Wi-Fi o microcel.les. Degut a aquest creixement estimat al tràfic dels dispositius móbils a entorns inalàmbrics, grans companyies estan invertint i centrant els seus recursos a les WLAN’s. Els interessos de la industria estan centrades en examinar les prestacions de las WLAN’s, especialment a entorns d’interior, i trovar mitjans per entendre millor la experiència d’usuari (UX) a situacions reals. Aquestes ambicions requereixen la combinació de coneixements tant teòrics com pràctics. Aquesta tesis està centrada en la estimació de prestacions. Amb aquest objectiu, una Interfície Gràfica d’Usuari (GUI) es desenvolupada per simular i analitzar diferents mètriques de les WLAN’s a entorns d’interior, tals com la cobertura o el data rate. Aquesta eina no només combina diferents coneixements avançats com la propagació en entorns d’interior, pèrdues de propagació, modelat de pisos, modelat de interferències o diferents estàndards de WLAN; sino que els combina i els presenta al usuari final a una interfície senzilla. Les métriques analitzades son representades quantitativament i amb la millor precissió possible. Quan l’eina es executada amb els valor introduits correctament, permeteix obtener valors com la Signal Strength, la SNR, SIR o la màxima Data Rate disponible; això permeteix als proveidors de serveis estimar les prestacions màximes dels seus sistemes i validar resultats teòrics emprant simulacions. L’eina dissenyada es una primera aproximació a un problema molt més complexe com es el modelat i la simulació completa de sistemes WLAN; per aiò incorpora escalabilitat permetent futures millores

    WLAN PERFORMANCE ANALYSIS FOR INDOOR ENVIRONMENTS ANÁLISIS DE LAS PRESTACIONES DE WLAN'S EN ENTORNOS DE INTERIOR ANÀLISIS DE LES PRESTACIONS DE WLAN'S A ENTORNS D' INTERIOR

    No full text
    The thesis is dedicated to the analysis of cryptographic algorithms and protocols with respect to their applicability for hardware implementation in different environments and under different constraints and optimization goals (high-throughput vs. low power). Therefore, selected algorithms will be implemented and evaluated in Hardware (FPGA, GPU) and their performance will be compared to the existing Open Source software solution. The work shall follow scientific standards and the developed code will be released under an Open Source license on the project site. AIT willStudies report that in the next years there will be a high increase in the number of mobile devices, the overall data traffic generated by mobile devices, and a migration from larger cells towards Wireless Local Area Networks (WLAN) and smaller cells (picocells and femtocells). There is also a large amount of data that is estimated to be offloaded to Wi-Fi and small cells. Due to this estimated growth in the mobile data traffic over wireless environment; several companies are investing and focusing resources in improving their services mainly related with WLAN’s. The concerns of the industry are focused on examining the performance of WLAN’s, especially indoors, and finding ways to understand more about actual User Experience (UX) in real scenarios. These ambitions require the combination of theory with practice. This thesis is mainly focused on supporting these performance estimations. Trying to help on this purpose, a Graphical User Interface (GUI) is developed for simulating and analysing certain metrics of WLAN´s in indoor environments, such as coverage and data rate. The tool not only combines several different advanced concepts relating to indoor propagation, penetration loss, layout modelling, interference modelling, and different WLAN standards; but presents them in a simple and easy-to-understand interface to the final user. The performance metrics are represented quantitatively and as accurately as possible. When the tool is run with appropriate input values, it is able to provide results such as the Signal Strength, Signal to Noise Ratio (SNR), Signal to Interference Ratio (SIR) and maximum achievable Data Rate; this allows the service providers to estimate the maximum performance of their own systems and also to validate theoretical results by simulation. This tool is the first approach to a much more complex problem that is to fully model and simulate a full WLAN system; that is why its scalability allows future improvements.Estudios muestran que en los próximos años va a haber un gran incremento en el número de dispositivos móviles, de la media de tráfico generado por todos los dispositivos móviles, y una migración desde macroceldas a Redes Wireless de Área Local (WLAN) y microceldas (picoceldas y femtoceldas). También se estima un gran incremento en la cantidad de estos datos que serán descargados a través de Wi-Fi o microceldas. Debido a este crecimiento estimado en el tráfico de los dispositivos móviles en el entorno inalámbrico, grandes compañías están invirtiendo y centrando sus recursos en las WLAN’s. Los intereses de la industria se centran en examinar las prestaciones de las WLAN’s, especialmente en entornos de interior, y encontrar medios para entender más acerca de la experiencia de usuario (UX) en situaciones reales. Estas ambiciones requieren la combinación de conocimiento tanto teórico como práctico. Esta tesis se centra principalmente en apoyar la estimación de prestaciones. Con esta finalidad, se desarrolla una Interfaz Gráfica de Usuario (GUI) para simular y analizar ciertas métricas de las WLAN’s en entornos de interior, tales como la cobertura o el data rate. La herramienta no solo combina diferentes conceptos avanzados relacionados con la propagación en entornos de interior, pérdidas de propagación, modelado de pisos, modelado de interferencias o diferentes estándares de WLAN; pero a la vez los presenta de manera simple y entendible en una interfaz para el usuario final. Las métricas analizadas se representan cuantitativamente y con la mayor precisión posible. Cuando se ejecuta la herramienta con los valores introducidos correctos, permite obtener valores como la Signal Strength, la SNR, SIR o máximo Data Rate disponible; ésto permite a los proveedores de servicio estimar las prestaciones máximas de sus sistemas y además validar resultados teóricos mediante simulación. La herramienta diseñada es una primera aproximación a un problema mucho más complejo como es el modelado y la simulación íntegra de un sistema WLAN; para ello ha sido incorporada escalabilidad, permitiendo futuras mejoras.Estudis mostren que als pròxims anys hi haurà un gran increment al nombre de dispositius móbils, de la mitjana de tràfic generat per tots els dispositius móbils i una migració de macrocel.les a xarxes inalàmbriques de Àrea Local (WLAN) i microcel.les (picocel.les I femtocel.les). També s’estima un gran augment en la quantitat d’aquestes dades que ser’an descarregats per mitjà de Wi-Fi o microcel.les. Degut a aquest creixement estimat al tràfic dels dispositius móbils a entorns inalàmbrics, grans companyies estan invertint i centrant els seus recursos a les WLAN’s. Els interessos de la industria estan centrades en examinar les prestacions de las WLAN’s, especialment a entorns d’interior, i trovar mitjans per entendre millor la experiència d’usuari (UX) a situacions reals. Aquestes ambicions requereixen la combinació de coneixements tant teòrics com pràctics. Aquesta tesis està centrada en la estimació de prestacions. Amb aquest objectiu, una Interfície Gràfica d’Usuari (GUI) es desenvolupada per simular i analitzar diferents mètriques de les WLAN’s a entorns d’interior, tals com la cobertura o el data rate. Aquesta eina no només combina diferents coneixements avançats com la propagació en entorns d’interior, pèrdues de propagació, modelat de pisos, modelat de interferències o diferents estàndards de WLAN; sino que els combina i els presenta al usuari final a una interfície senzilla. Les métriques analitzades son representades quantitativament i amb la millor precissió possible. Quan l’eina es executada amb els valor introduits correctament, permeteix obtener valors com la Signal Strength, la SNR, SIR o la màxima Data Rate disponible; això permeteix als proveidors de serveis estimar les prestacions màximes dels seus sistemes i validar resultats teòrics emprant simulacions. L’eina dissenyada es una primera aproximació a un problema molt més complexe com es el modelat i la simulació completa de sistemes WLAN; per aiò incorpora escalabilitat permetent futures millores

    Activity of a New Cephalosporin, CXA-101 (FR264205), against β-Lactam-Resistant Pseudomonas aeruginosa Mutants Selected In Vitro and after Antipseudomonal Treatment of Intensive Care Unit Patients▿

    No full text
    CXA-101, previously designated FR264205, is a new antipseudomonal cephalosporin. We evaluated the activity of CXA-101 against a highly challenging collection of β-lactam-resistant Pseudomonas aeruginosa mutants selected in vitro and after antipseudomonal treatment of intensive care unit (ICU) patients. The in vitro mutants investigated included strains with multiple combinations of mutations leading to several degrees of AmpC overexpression (ampD, ampDh2, ampDh3, and dacB [PBP4]) and porin loss (oprD). CXA-101 remained active against even the AmpD-PBP4 double mutant (MIC = 2 μg/ml), which shows extremely high levels of AmpC expression. Indeed, this mutant showed high-level resistance to all tested β-lactams, except carbapenems, including piperacillin-tazobactam (PTZ), aztreonam (ATM), ceftazidime (CAZ), and cefepime (FEP), a cephalosporin considered to be relatively stable against hydrolysis by AmpC. Moreover, CXA-101 was the only β-lactam tested (including the carbapenems imipenem [IMP] and meropenem [MER]) that remained fully active against the OprD-AmpD and OprD-PBP4 double mutants (MIC = 0.5 μg/ml). Additionally, we tested a collection of 50 sequential isolates that were susceptible or resistant to penicillicins, cephalosporins, carbapenems, or fluoroquinolones that emerged during treatment of ICU patients. All of the mutants resistant to CAZ, FEP, PTZ, IMP, MER, or ciprofloxacin showed relatively low CXA-101 MICs (range, 0.12 to 4 μg/ml; mean, 1 to 2 μg/ml). CXA-101 MICs of pan-β-lactam-resistant strains ranged from 1 to 4 μg/ml (mean, 2.5 μg/ml). As described for the in vitro mutants, CXA-101 retained activity against the natural AmpD-PBP4 double mutants, even when these exhibited additional overexpression of the MexAB-OprM efflux pump. Therefore, clinical trials are needed to evaluate the usefulness of CXA-101 for the treatment of P. aeruginosa nosocomial infections, particularly those caused by multidrug-resistant isolates that emerge during antipseudomonal treatments

    Regulation of AmpC-Driven beta-Lactam Resistance in Pseudomonas aeruginosa : Different Pathways, Different Signaling

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    The hyperproduction of the chromosomal AmpC β-lactamase is the main mechanism driving β-lactam resistance in Pseudomonas aeruginosa, one of the leading opportunistic pathogens causing nosocomial acute and chronic infections in patients with underlying respiratory diseases. In the current scenario of the shortage of effective antipseudomonal drugs, understanding the molecular mechanisms mediating AmpC hyperproduction in order to develop new therapeutics against this fearsome pathogen is of great importance. It has been accepted for decades that certain cell wall-derived soluble fragments (muropeptides) modulate AmpC production by complexing with the transcriptional regulator AmpR and acquiring different conformations that activate/repress ampC expression. However, these peptidoglycan-derived signals have never been characterized in the highly prevalent P. aeruginosa stable AmpC hyperproducer mutants. Here, we demonstrate that the previously described fragments enabling the transient ampC hyperexpression during cefoxitin induction (1,6-anhydro-N-acetylmuramyl-pentapeptides) also underlie the dacB (penicillin binding protein 4 [PBP4]) mutation-driven stable hyperproduction but differ from the 1,6-anhydro-N-acetylmuramyl-tripeptides notably overaccumulated in the ampD knockout mutant. In addition, a simultaneous greater accumulation of both activators appears linked to higher levels of AmpC hyperproduction, although our results suggest a much stronger AmpC-activating potency for the 1,6-anhydro-N-acetylmuramyl-pentapeptide. Collectively, our results propose a model of AmpC control where the activator fragments, with qualitative and quantitative particularities depending on the pathways and levels of β-lactamase production, dominate over the repressor (UDP-N-acetylmuramyl-pentapeptide). This study represents a major step in understanding the foundations of AmpC-dependent β-lactam resistance in P. aeruginosa, potentially useful to open new therapeutic conceptions intended to interfere with the abovementioned cell wall-derived signaling. IMPORTANCE: The extensive use of β-lactam antibiotics and the bacterial adaptive capacity have led to the apparently unstoppable increase of antimicrobial resistance, one of the current major global health challenges. In the leading nosocomial pathogen Pseudomonas aeruginosa, the mutation-driven AmpC β-lactamase hyperproduction stands out as the main resistance mechanism, but the molecular cues enabling this system have remained elusive until now. Here, we provide for the first time direct and quantitative information about the soluble cell wall-derived fragments accounting for the different levels and pathways of AmpC hyperproduction. Based on these results, we propose a hierarchical model of signals which ultimately govern ampC hyperexpression and resistance

    Improving Properties of Starch-Based Adhesives with Carboxylic Acids and Enzymatically Polymerized Lignosulfonates

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    A novel strategy for improving wet resistance and bonding properties of starch-based adhesives using enzymatically polymerized lignosulfonates and carboxylic acids as additives was developed. Therefore, lignosulfonates were polymerized by laccase to a molecular weight of 750 kDa. Incorporation of low concentrations (up to 1% of the starch weight) of 1,2,3,4-butanetetracarboxylic acid (BTCA) led to further improvement on the properties of the adhesives, while addition of greater amounts of BTCA led to a decrease in the properties measured due to large viscosity increases. Great improvements in wet-resistance from 22 to 60 min and bonding times (from 30 to 20 s) were observed for an adhesive containing 8% enzymatically polymerized lignin and 1% BTCA. On the other hand, the addition of citric acid (CA) deteriorated the properties of the adhesives, especially when lignosulfonate was present. In conclusion, this study shows that the addition of the appropriate amount of enzymatically polymerized lignosulfonates together with carboxylic acids (namely BTCA) to starch-based adhesives is a robust strategy for improving their wet resistance and bonding times
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