Molecular Mechanisms Used by Salmonella to Evade the Immune System

Human and animal pathogens are able to circumvent, at least temporarily, the sophisticated immune defenses of their hosts. Several serovars of the Gram-negative bacterium Salmonella enterica have been used as models for the study of pathogen-host interactions. In this review we discuss the strategies used by Salmonella to evade or manipulate three levels of host immune defenses: physical barriers, innate immunity and adaptive immunity. During its passage through the digestive system, Salmonella has to face the acidic pH of the stomach, bile and antimicrobial peptides in the intestine, as well as the competition with resident microbiota. After host cell invasion, Salmonella manipulates inflammatory pathways and the autophagy process. Finally, Salmonella evades the adaptive immune system by interacting with dendritic cells, and T and B lymphocytes. Mechanisms allowing the establishment of persistent infections are also discussed.European Regional Development Fund SAF2013-46229-R, SAF2016-75365-

Type III Secretion Effectors with Arginine N-Glycosyltransferase Activity

Type III secretion systems are used by many Gram-negative bacterial pathogens to inject proteins, known as effectors, into the cytosol of host cells. These virulence factors interfere with a diverse array of host signal transduction pathways and cellular processes. Many effectors have catalytic activities to promote post-translational modifications of host proteins. This review focuses on a family of effectors with glycosyltransferase activity that catalyze addition of N-acetyl-d-glucosamine to specific arginine residues in target proteins, leading to reduced NF-κB pathway activation and impaired host cell death. This family includes NleB from Citrobacter rodentium, NleB1 and NleB2 from enteropathogenic and enterohemorrhagic Escherichia coli, and SseK1, SseK2, and SseK3 from Salmonella enterica. First, we place these effectors in the general framework of the glycosyltransferase superfamily and in the particular context of the role of glycosylation in bacterial pathogenesis. Then, we provide detailed information about currently known members of this family, their role in virulence, and their targetsSpanish Ministerio de Economía, Industria y Competitividad , Agencia Estatal de Investigación, and the European Regional Development Fund, grant number SAF2016‐75365‐REuropean Union’s Horizon 2020 e Marie Skłodowska‐Curie grant agreement No 84262

Self-Concealment, Perceived Discrimination, and African American Treatment Choices for Major Depression

African Americans have a higher proclivity to depression than other ethnic groups in the United States and also have a greater propensity to avoid seeking professional mental health treatment. The available research has shown that racial and cultural barriers such as perceived discrimination and self-concealment are the primary factors that negatively affect African Americans\u27 attitudes toward mental health itself and mental health treatment. Perceived discrimination and self-concealment may also negatively affect whether African Americans seek help for depression and from whom, but further investigation was needed. The quantitative survey study provided answers to which factors influence whether and where African Americans seek help for major depression. A total of 147 participants were recruited through word of mouth, local churches, community organizations, and virtual venues such as electronic mail and social media. Multivariate analysis of variance revealed the mean scores of African Americans\u27 use of natural supports and their use of outpatient treatment (dependent variables) were not equal across all levels of their self-concealment, perceived discrimination, and depressive symptoms (independent variables). Multivariate analysis of covariance revealed that the mean scores remained the same when controlling for gender, income, education, and relationship status (covariates). The results suggest that the latter factors influence African Americans\u27 decisions on where to seek help for depression regardless of their gender and socioeconomic status. Increasing the propensity of African Americans to seek professional help for depression should improve the mental health of the population as a whole and reduce the incidents of serious mental illness of those who are treated

Toeplitz operators, pseudo-homogeneous symbols and moment maps on the complex projective space

Following previous works for the unit ball, we define quasi-radial pseudo-homogeneous symbols on the projective space and obtain the corresponding commutativity results for Toeplitz operators. A geometric interpretation of these symbols in terms of moment maps is developed. This leads us to the introduction of a new family of symbols, extended pseudo-homogeneous, that provide larger commutative Banach algebras generated by Toeplitz operators. This family of symbols provides new commutative Banach algebras generated by Toeplitz operators on the unit ball

Selenium persistency and speciation in the tissues of lambs following the withdrawal of dietary high-dose selenium-enriched yeast

The objective was to determine the concentration of total selenium (Se) and the proportion of total Se comprised as selenomethionine (SeMet) and selenocysteine (SeCys) in post mortem tissues of lambs in the six weeks period following the withdrawal of a diet containing high dose selenized yeast (SY), derived from a specific strain of Saccharomyces cerevisae CNCM (Collection Nationale de Culture de Micro-organism) I-3060. Thirty Texel x Suffolk lambs used in this study had previously received diets (91 days) containing either high dose SY (HSY; 6.30 mg Se/kg DM) or an unsupplemented control (C; 0.13 mg Se/kg DM). Following the period of supplementation all lambs were then offered a complete pelleted diet, without additional Se (0.15 mg Se/kg DM), for 42 days. At enrollment and 21 and 42 days later, five lambs from each treatment were blood sampled, euthanased and samples of heart, liver, kidney and skeletal muscle (Longissimus Dorsi and Psoas Major) tissue were retained. Total Se concentration in whole blood and tissues was significantly (P < 0.001) higher in HSY lambs at all time points that had previously received long term exposure to high dietary concentrations of SY. The distribution of total Se and the proportions of total Se comprised as SeMet and SeCys differed between tissues, treatment and time points. Total Se was greatest in HSY liver and kidney (22.64 and 18.96 mg Se/kg DM, respectively) and SeCys comprised the greatest proportion of total Se. Conversely, cardiac and skeletal muscle (Longissimus Dorsi and Psoas Major) tissues had lower total Se concentration (10.80, 7.02 and 7.82 mg Se/kg DM, respectively) and SeMet was the predominant selenized amino acid. Rates of Se clearance in HSY liver (307 µg Se/day) and kidney (238 µg Se/day) were higher compared with HSY cardiac tissue (120 µg Se/day) and skeletal muscle (20 µg Se/day). In conclusion differences in Se clearance rates were different between tissue types, reflecting the relative metabolic activity of each tissue, and appear to be dependant upon the proportions of total Se comprised as either SeMet or SeCys

The returns to education in Mexico

This paper estimates private returns to education in Mexico by means of the Mincer model. The natural ability bias that the literature reports in this type of estimations is tried to be solved using the control function method. Through this method some variables relevant to wage determination are included in the model, such as natural ability index, mother's education, household infrastructure, height and health. Results suggest that the returns to education by year of schooling in Mexico are between 8.2 % and 8.4 %. On the other hand, results by level of education suggest that more education is associated with higher returns. The highest return to education in both absolute and relative terms is provided by Postgraduate education followed by Graduate education. In general, results suggest that there is a convex relationship between education level and wage.Private returns to education, natural ability bias, natural ability index, mother's education, Mexico.

Objetivos clave de las Ciencias Marinas Españolas en el contexto europeo (2003-2007)

[EN] The analysis of the marine projects funded by the Spanish RTD funding agency between 2003 and 2007 in the framework of the European policies, showed that although the funds available have increased (232 projects and 33 Million € from 2003 to 2007) there are still research and strategic areas that are not covered. The relevance of marine related services and economic revenues for Spain requires that a strategy is developed to address the challenges that are emerging due to the growing competing uses of the sea, which include maritime transport, fishing, aquaculture, leisure activities, off-shore energy production and other forms of seabed exploitation. By helping to develop a more sophisticated understanding of the impact of human activities on marine systems, scientific research and technology may provide the key to carrying out seabased activities without degrading the environment, and to predicting and mitigating as far as possible the effects of climate change.[ES] Dentro del marco de las políticas europeas, el análisis de los proyectos sobre el medio marino sufragados por la Agencia Española de Investigación, Desarrollo e Innovación (I+D+I) durante los años 2003-2007 pone de manifiesto que, aunque se han incrementado las subvenciones concedidas (232 proyectos y 33 millones de euros en dicho período), existen todavía sin cubrir determinadas áreas estratégicas y de investigación. La relevancia para España de los servicios e ingresos económicos relacionados con el medio marino requiere que se desarrolle una estrategia que dirija los desafíos resultantes de la creciente competencia de usos que el mar genera, tanto desde el punto de vista del transporte marítimo, la pesca, la acuicultura, el ocio, la producción de energía en mar abierto, como de otras formas de explotación del fondo marino. Para ayudar a desarrollar una mejor y más sofisticada comprensión del impacto de las actividades humanas sobre los sistemas marinos, la investigación científica y la tecnología deben ser capaces de proporcionar las claves necesarias para desacoplar de la degradación ambiental las actividades de explotación relacionadas con el mar, de modo que se predigan y atenúen tanto como sea posible los efectos del cambio climático.Peer reviewe

Effectiveness of foot orthosis in patients with rheumatoid arthritis related to quality of life and pain. A systematic review and meta-analysis

Foot pain and deformity is almost ubiquitous in RA and results in considerable physical and psychosocial impairment. Epidemiological studies consistently suggest a 90% prevalence of foot pain despite advances in pharmacological therapy. Mechanical and other non-pharmacological interventions such as orthoses and footwear, have an important role in managing foot pathology in patients with their systemic disease controlled. The effectiveness of treatment with insoles, especially in early periods, was studied in a randomized controlled trial, which results suggested an immediate clinical improvement, reducing foot pain, disability and limited functionality.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Patterns of expression and translocation of the ubiquitin ligase SlrP in Salmonella enterica serovar typhimurium.

SlrP is an E3 ubiquitin ligase that can be translocated into eukaryotic host cells by the two type III secretion systems that are expressed by Salmonella enterica serovar Typhimurium and are encoded in Salmonella pathogenicity islands 1 (SPI1) and 2 (SPI2). Expression of slrP and translocation of its product were examined using lac, 3×FLAG, and cyaA′ translational fusions. Although slrP was expressed in different media, optimal expression was found under conditions that imitate the intravacuolar environment and promote synthesis of the SPI2-encoded type III secretion system. Translocation into mammalian cells took place through the SPI1- or the SPI2-encoded type III secretion system, depending on specific host cell type and timing. A search for genetic factors involved in controlling the expression of slrP unveiled LeuO, Lon, and the two-component system PhoQ/PhoP as novel regulators of slrP. Our experiments suggest that LeuO and Lon act through HilD under SPI1-inducing conditions, whereas PhoP directly interacts with the slrP promoter to activate transcription under SPI2 inducing conditions