The Prc and CtpA proteases modulate cell-surface signaling activity and virulence in Pseudomonas aeruginosa.

Cell-surface signaling (CSS) is a signal transfer system of Gram-negative bacteria that produces the activation of an extracytoplasmic function σ factor (σECF) in the cytosol in response to an extracellular signal. Activation requires the regulated and sequential proteolysis of the σECF-associated anti-σ factor, and the function of the Prc and RseP proteases. In this work, we have identified another protease that modulates CSS activity, namely the periplasmic carboxyl-terminal processing protease CtpA. CtpA functions upstream of Prc in the proteolytic cascade and seems to prevent the Prc-mediated proteolysis of the CSS anti-σ factor. Importantly, using zebrafish embryos and the A549 lung epithelial cell line as hosts, we show that mutants in the rseP and ctpA proteases of the human pathogen Pseudomonas aeruginosa are considerably attenuated in virulence while the prc mutation increases virulence likely by enhancing the production of membrane vesicles.

Clover Root Exudates Favor Novosphingobium sp. HR1a Establishment in the Rhizosphere and Promote Phenanthrene Rhizoremediation.

Rhizoremediation is based on the ability of microorganisms to metabolize nutrients from plant root exudates and, thereby, to cometabolize or even mineralize toxic environmental contaminants. Novosphingobium sp. HR1a is a bacterial strain able to degrade a wide variety of polycyclic aromatic hydrocarbons (PAHs). Here, we have demonstrated that the number of CFU in microcosms vegetated with clover was almost 2 orders of magnitude higher than that in nonvegetated microcosms or microcosms vegetated with rye-grass or grass. Strain HR1a was able to eliminate 92% of the phenanthrene in the microcosms with clover after 9 days. We have studied the molecular basis of the interaction between strain HR1a and clover by phenomic, metabolomic, and transcriptomic analyses. By measuring the relative concentrations of several metabolites exudated by clover both in the presence and in the absence of the bacteria, we identified some compounds that were probably consumed in the rhizosphere; the transcriptomic analyses confirmed the expression of genes involved in the catabolism of these compounds. By using a transcriptional fusion of the green fluorescent protein (GFP) to the promoter of the gene encoding the dioxygenase involved in the degradation of PAHs, we have demonstrated that this gene is induced at higher levels in clover microcosms than in nonvegetated microcosms. Therefore, the positive interaction between clover and Novosphingobium sp. HR1a during rhizoremediation is a result of the bacterial utilization of different carbon and nitrogen sources released during seedling development and the capacity of clover exudates to induce the PAH degradation pathway. IMPORTANCE The success of an eco-friendly and cost-effective strategy for soil decontamination is conditioned by the understanding of the ecology of plant-microorganism interactions. Although many studies have been published about the bacterial metabolic capacities in the rhizosphere and about rhizoremediation of contaminants, there are fewer studies dealing with the integration of bacterial metabolic capacities in the rhizosphere during PAH bioremediation, and some aspects still remain controversial. Some authors have postulated that the presence of easily metabolizable carbon sources in root exudates might repress the expression of genes required for contaminant degradation, while others found that specific rhizosphere compounds can induce such genes. Novosphingobium sp. HR1a, which is our model organism, has two characteristics desirable in bacteria for use in remediation: its ubiquity and the capacity to degrade a wide variety of contaminants. We have demonstrated that this bacterium consumes several rhizospheric compounds without repression of the genes required for the mineralization of PAHs. In fact, some compounds even induced their expression.

Effects of fear of crime on subjective well-being: a meta-analytic review / Los efectos del miedo al delito en el bienestar subjetivo: revisión metaanalítica

We analyzed 12 studies from North America, South America, Europe, and Oceania (New Zealand) on the association between fear of crime and subjective well-being. These studies gather data from 39 countries and 407,474 subjects. Heterogeneity was found between the studies. The random effect model showed an average effect of = -.15 (ρ = -.21). Two of the studies estimated fear of crime with a single generic question and five studies assessed subjective well-being through one item of satisfaction with life. Meta-regression showed that the effect was superior in younger samples, with affective measurement of well-being in comparison with cognitive ones, of mono-item (versus multi-items) and in the countries of Latin America, suggesting that in contexts of greater frequency and seriousness of the crime the fear of crime negatively affects subjective well-being. The diffuse or concrete nature of the measure of fear did not show a significant moderator effect. Limitations of the study and proposals for future research are discussed

Se analizaron 12 estudios de Norteamérica, Latinoamérica, Europa y Oceanía (Nueva Zelanda) con respecto a la asociación entre el miedo al delito y el bienestar subjetivo. Los estudios reúnen información de 39 países y 407,474 sujetos. Se encontró heterogeneidad entre los estudios. El modelo de efectos aleatorios mostró un efecto promedio de = -.15 (ρ = -.21). Dos estudios evaluaron el miedo al delito con una sola pregunta genérica, mientras que cinco estudios midieron el bienestar subjetivo con un ítem de satisfacción con la vida. La meta-regresión mostró que el efecto fue superior en muestras más jóvenes, con medidas afectivas del bienestar subjetivo en comparación con medidas cognitivas de un solo ítem (versus medidas poli-item), y en países de Latinoamérica, sugiriendo que en contextos de mayor frecuencia y severidad del crimen el miedo al delito afecta negativamente al bienestar subjetivo. La naturaleza difusa o concreta de la medida de miedo al delito no mostró un efecto moderador. Se debaten las limitaciones del estudio y las propuestas para futuras investigaciones

Degradation of phenanthrene by Novosphingobium sp. HS2a improved plant growth in PAHs-contaminated environments.

At the same time that the European Union (EU) policy recommend to direct efforts towards reductions of heavy metals, polycyclic aromatic hydrocarbons (PAHs) and mining residues, there is the need to increase the cultivable areas within Europe to cope with the increasing demands for food and energy crops. Bioremediation is a good technique for the restoration of contaminated soils; however, it has not been used extensively because of the variability of the outcome. This variability is frequently due to a bad establishment of foreign degrading populations in soil. We have demonstrated that Novosphingobium sp. HS2aR (i) is able to compete with other root colonizers and with indigenous bacteria, (ii) is able to establish in high numbers in the contaminated environments and (iii) is able to remove more than 90 % of the extractable phenanthrene in artificially contaminated soils. Furthermore, we have demonstrated that the capacity to remove phenanthrene is linked to the ability to promote plant growth in contaminated environments. The fact that the presence of Novosphingobium sp. HS2aR improves the growth of plants in contaminated soil suggests that it may be a useful strain for utilization in amelioration of soil quality while improving the growth of economically important energy crops, thus adding value to the bioremediation strategy.

The pGRT1 plasmid of Pseudomonas putida DOT-T1E encodes functions relevant for survival under harsh conditions in the environment.

Pseudomonas putida DOT-T1E has the capacity to grow in the presence of high concentrations of toluene. This ability is mainly conferred by an efflux pump encoded in a self-transmissible 133 kb plasmid named pGRT1. Sequence analysis of the pGRT1 plasmid revealed several key features. Most of the genes related to the plasmid maintenance functions show similarity with those encoded on pBVIE04 from Burkholderia vietnamensis G4, and knock-out mutants in several of these genes confirmed their roles. Two additional plasmid DNA fragments were incorporated into the plasmid backbone by recombination and/or transposition; in these DNA regions, apart from multiple recombinases and transposases, several stress-related and environmentally relevant functions are encoded. We report that plasmid pGRT1 not only confers the cells with tolerance to toluene but also resistance to ultraviolet light. We show here the implication of a new protein in solvent tolerance which controls the level of expression of the TtgGHI efflux pump, as well as the implication of a protein with homology to the universal stress protein in solvent tolerance and ultraviolet light resistance. Furthermore, this plasmid encodes functions that allow the cells to chemotactically respond to toluene and participate in iron scavenging.

Comparison of three rating scales for measuring subjective phenomena in clinical research. I. Use of experimentally controlled auditory stimuli.

BACKGROUND: An interest in measuring subjective phenomena such as pain, nausea, anxiety, etc. has led clinicians to develop three types of ratings: the visual analog scale (VAS); the verbal rating scale (VRS), and the numeric rating score (NRS). These ratings are regarded as global scales because they lack criteria to demarcate diverse dimensions or categories that comprise each scale. The purpose of this study was to evaluate validity and consistency of usage for these scales. Criterion for validity consisted of an experimentally controlled intensity for auditory stimuli. METHODS: We conducted a prospective, experimentally controlled, clinimetric study at the Audiology Department at the Hospital of Puebla Autonomous University (in Puebla State, Mexico). Participants included 25 medical students, two psychology students, and three practicing physicians. Interventions consisted of pure 1,000 Hz tones in five different intensities applied for 3 sec with a 1-min interval between stimuli at three sessions for each observer. Main outcome measure was validity and consistency of usage for VAS, VRS, and NRS scales. RESULTS: Correlation coefficients between scale results and standard stimuli were 0.818 for VAS, 0.735 for NRS, and 0.796 for VRS. Mean weighted kappa indices for intraobserver agreement were 0.70, 0.59, and 0.65, respectively, for scales with five categories each. Mean weighted kappa indices for inter-observer variability were 0.61, 0.48, and 0.54 for VAS, NRS, and VRS again with five categories each. CONCLUSIONS: The three instruments appeared reasonably accurate, with VAS having highest scores. VRS appeared sufficiently consistent to be regarded as providing reliable scientific information.

Consistencia y validez de las subescalas del cuestionario de Conners para la evaluaicón de psicopatología en niños - versión larga para padres / Reliability and validity of the subscales of Conners' parents rating scale-long version

Introducción. Por lo frecuente de los síntomas de psicopatología en niños se requiere de instrumentos para la detección y evaluación de la misma. Objetivo: determinar la validez y consistencia de las subescalas del Cuestionario Conners para la evaluación de psicopatología en niños, en su versión larga para padres. Este cuestionario se seleccionó porque es de los empleados con más frecuencia y porque incluye un espectro amplio de síntomas de psicopatología que se presentan en los niños. Consta de 93 reactivos agrupados en 8 subescalas. Material y métodos. Se evaluaron 745 escolares que asistían a una escuela primaria pública: 53 por ciento niños y 42 por ciento niñas (en 5 por ciento no se anotó el sexo), con edad promedio de 9.26 años. Utilizándose el alpha de Cronbach y haciendo un análisis de reactivos de la subescalas propuestas. Resultados. Mediante un análisis factorial con rotación varimax se obtuvo una estructura factorial muy similar a la de Conners, con 9 factores: trastornos de la conducta, antisocial, ansioso-depresivo, problemas escolares, síntomas psicosomáticos, obsesivo-compulsivo, inmadurez, tensión muscular y problemas de lenguaje. La estructura de 4 de los 9 fue casi idéntica a las de las subescalas correspondientes de Conners. Por medio del alpha de Cronbach y del análisis de reactivos se encontró que estos factores tienen una consistencia adecuada. Conclusión. Las escalas propuestas por Conners son válidas y confiables. Pueden ser empleadas en la forma descrita y pueden complementarse con las que se están proponiendo