Human metapneumovirus: Mechanisms and molecular targets used by the virus to avoid the immune system

Indexación: Scopus.This work was supported by Comisión Nacional de Investigación Científica y Tecnolígica (CONICYT) N◦21151028 and FONDECYT (N◦1070352 and N◦1170964) and the Millennium Institute on Immunology and Immunotherapy (P09/016-F).Human metapneumovirus (hMPV) is a respiratory virus, first reported the year 2001. Since then, it has been described as one of the main etiological agents that causes acute lower respiratory tract infections (ALRTIs), which is characterized by symptoms such as bronchiolitis, wheezing and coughing. Susceptible population to hMPV-infection includes newborn, children, elderly and immunocompromised individuals. This viral agent is a negative-sense, single-stranded RNA enveloped virus, that belongs to the Pneumoviridae family and Metapneumovirus genus. Early reports-previous to 2001-state several cases of respiratory illness without clear identification of the responsible pathogen, which could be related to hMPV. Despite the similarities of hMPV with several other viruses, such as the human respiratory syncytial virus or influenza virus, mechanisms used by hMPV to avoid the host immune system are still unclear. In fact, evidence indicates that hMPV induces a poor innate immune response, thereby affecting the adaptive immunity. Among these mechanisms, is the promotion of an anergic state in T cells, instead of an effective polarization or activation, which could be induced by low levels of cytokine secretion. Further, the evidences support the notion that hMPV interferes with several pattern recognition receptors (PRRs) and cell signaling pathways triggered by interferon-associated genes. However, these mechanisms reported in hMPV are not like the ones reported for hRSV, as the latter has two non-structural proteins that are able to inhibit these pathways. Several reports suggest that viral glycoproteins, such as G and SH, could play immune-modulator roles during infection. In this work, we discuss the state of the art regarding the mechanisms that underlie the poor immunity elicited by hMPV. Importantly, these mechanisms will be compared with those elicited by other common respiratory viruses. © 2018 Frontiers Media S.A. All rights reserved.https://www.frontiersin.org/articles/10.3389/fimmu.2018.02466/ful

Effects of manufacturing tolerances of permanent magnets in fractional slot permanent magnet synchronous machines

The fractional slot permanent magnet synchronous machines are well-known for their low torque ripple. However, in mass-production machines, not all the permanent magnets are identical due to the manufacturing tolerances and new torque harmonics could appear. In addition, the magnetic field is modified and unbalanced magnetic pull (UMP) could happen. Apart from that it is important to study the effect on vibrations since the magnetic field is no longer ideal. So, here, a study of the effect of unevenly magnetised permanent magnet distribution on torque ripples, unbalance magnetic pull, and vibrations is proposed. Apart from that, the tolerance grade sensitivity is studied. Finally, experimental tests show good agreement with finite element analysis

Linfangioma quístico mesentérico en el diagnóstico diferencial de la enfermedad inflamatoria pélvica

La enfermedad inflamatoria pélvica (EIP) es un síndrome clínico que incluye todas aquellas alteraciones inflamatorias e infecciosas que comprenden los órganos de la pelvis menor. La infección es habitualmente polimicrobiana y está asociada a mujeres jóvenes con vida sexual activa, nulíparas y usuarias de dispositivo intrauterino (DIU Los abscesos tubo-ováricos son una complicación aguda o crónica, asociada a dicho proceso.). CASO CLÍNICO Presentamos el caso de una mujer de 47 años con dolor abdominal intenso, usuaria de DIU. La primera sospecha diagnóstica fue de EIP con presencia de absceso tuboovárico anexial. Sin embargo la exploración física no orientó en este sentido, por lo que se solicitó TAC abdominopélvico, en el que se informó de la posibilidad de linfangioma quístico mesentérico. Por ello, se contactó con el servicio de Cirugía General que procedió a su resección satisfactoria y sin incidencias. El estudio anatomopatológico confirmo la sospecha radiológica. CONCLUSIÓN Una adecuada exploración física es fundamental en el diagnóstico de la EIP y el absceso tuboovárico. El linfangioma quístico mesentérico puede formar parte del diagnóstico diferencial de las masas anexiales en este contexto. Pelvic inflammatory disease (PID) is a clinical syndrome involving all those inflammatory and infectious alterations affecting the minor pelvis organs. Any infection is often multibacterial and more frequent in sexually active nulliparous young women and intrauterine device (IUD) users. Tuboovarian abscesses can be an acute or chronic complication associated to that process. Our patient was a 47 year old IUD user consulting about intense abdominal pain. The initial clinical suspicion pointed at a case of PID associated to a tubo-ovarian anexial abscess. However, a physical examination did not support this suspicion and an abdominopelvian CAT scan was therefore requested, reporting a possible mesenteric cystic lymphangioma. The General Surgery service was reached for treatment, successfully excising the growth without further incident. Histological analysis confirmed the radiological diagnosis. An adequate physical examination is instrumental while diagnosing PID and tuboovarian abscesses. A mesenteric cystic lymphangioma should be included in a differential diagnosis of anexial growths in such a contex

Moduli of Abelian varieties, Vinberg theta-groups, and free resolutions

We present a systematic approach to studying the geometric aspects of Vinberg theta-representations. The main idea is to use the Borel-Weil construction for representations of reductive groups as sections of homogeneous bundles on homogeneous spaces, and then to study degeneracy loci of these vector bundles. Our main technical tool is to use free resolutions as an "enhanced" version of degeneracy loci formulas. We illustrate our approach on several examples and show how they are connected to moduli spaces of Abelian varieties. To make the article accessible to both algebraists and geometers, we also include background material on free resolutions and representation theory.Comment: 41 pages, uses tabmac.sty, Dedicated to David Eisenbud on the occasion of his 65th birthday; v2: fixed some typos and added reference

Implementation of a Markov Chain Monte Carlo method to inorganic aerosol modeling of observations from the MCMA-2003 campaign ? Part I: Model description and application to the La Merced site

International audienceThe equilibrium inorganic aerosol model ISORROPIA was embedded in a Markov Chain Monte Carlo algorithm to develop a powerful tool to analyze aerosol data and predict gas phase concentrations where these are unavailable. The method directly incorporates measurement uncertainty, prior knowledge, and provides a formal framework to combine measurements of different quality. The method was applied to particle- and gas-phase precursor observations taken at La Merced during the Mexico City Metropolitan Area (MCMA) 2003 Field Campaign and served to discriminate between diverging gas-phase observations of ammonia and predict gas-phase concentrations of hydrochloric acid. The model reproduced observations of particle-phase ammonium, nitrate, and sulfate well. The most likely concentrations of ammonia were found to vary between 4 and 26 ppbv, while the range for nitric acid was 0.1 to 55 ppbv. During periods where the aerosol chloride observations were consistently above the detection limit, the model was able to reproduce the aerosol chloride observations well and predicted the most likely gas-phase hydrochloric acid concentration varied between 0.4 and 5 ppbv. Despite the high ammonia concentrations observed and predicted by the model, when the aerosols were assumed to be in the efflorescence branch they are predicted to be acidic (pH~3)

Effects of cryopreservation on viability and functional stability of an industrially relevant alga

As algal biotechnology develops, there is an increasing requirement to conserve cultures without the cost, time and genetic stability implications of conventional serial transfers, including issues regarding potential loss by failure to regrow, contamination on transfer, mix up and/or errors in the documentation on transfer. Furthermore, it is crucial to ensure both viability and functionality are retained by stored stock-cultures. Low temperature storage, ranging from the use of domestic freezers to storage under liquid nitrogen, is widely being used, but the implication to stability and function rarely investigated. We report for the first time, retention of functionality in the maintenance of master stock-cultures of an industrially relevant, lipid-producing alga, under a variety of cryopreservation regimes. Storage in domestic (−15 °C), or conventional −80 °C freezers was suboptimal, with a rapid reduction in viability observed for samples at −15 °C and a >50% loss of viability, within one month, for samples stored at −80 °C. No reduction in viability occurred at −196 °C. Post-thaw culture functional performance was also influenced by the cryopreservation approach employed. Only samples held at −196 °C responded to nitrogen limitation in terms of growth characteristics and biochemical profiles (lipid production and chlorophyll a) comparable to the untreated control, cultured prior to cryopreservation. These results have important implications in microbial biotechnology, especially for those responsible for the conservation of genetic resources

Potential of atoxigenic Aspergillus flavus vegetative compatibility groups associated with maize and groundnut in Ghana as biocontrol agents for aflatoxin management

Open Access Journal; Published online: 06 Sept 2019Increasing knowledge of the deleterious health and economic impacts of aflatoxin in crop commodities has stimulated global interest in aflatoxin mitigation. Current evidence of the incidence of Aspergillus flavus isolates belonging to vegetative compatibility groups (VCGs) lacking the ability to produce aflatoxins (i.e., atoxigenic) in Ghana may lead to the development of an aflatoxin biocontrol strategy to mitigate crop aflatoxin content. In this study, 12 genetically diverse atoxigenic African A. flavus VCGs (AAVs) were identified from fungal communities associated with maize and groundnut grown in Ghana. Representative isolates of the 12 AAVs were assessed for their ability to inhibit aflatoxin contamination by an aflatoxin-producing isolate in laboratory assays. Then, the 12 isolates were evaluated for their potential as biocontrol agents for aflatoxin mitigation when included in three experimental products (each containing four atoxigenic isolates). The three experimental products were evaluated in 50 maize and 50 groundnut farmers’ fields across three agroecological zones (AEZs) in Ghana during the 2014 cropping season. In laboratory assays, the atoxigenic isolates reduced aflatoxin biosynthesis by 87–98% compared to grains inoculated with the aflatoxin-producing isolate alone. In field trials, the applied isolates moved to the crops and had higher (P < 0.05) frequencies than other A. flavus genotypes. In addition, although at lower frequencies, most atoxigenic genotypes were repeatedly found in untreated crops. Aflatoxin levels in treated crops were lower by 70–100% in groundnut and by 50–100% in maize (P < 0.05) than in untreated crops. Results from the current study indicate that combined use of appropriate, well-adapted isolates of atoxigenic AAVs as active ingredients of biocontrol products effectively displace aflatoxin producers and in so doing limit aflatoxin contamination. A member each of eight atoxigenic AAVs with superior competitive potential and wide adaptation across AEZs were selected for further field efficacy trials in Ghana. A major criterion for selection was the atoxigenic isolate’s ability to colonize soils and grains after release in crop field soils. Use of isolates belonging to atoxigenic AAVs in biocontrol management strategies has the potential to improve food safety, productivity, and income opportunities for smallholder farmers in Ghana

Implementation of a Markov Chain Monte Carlo method to inorganic aerosol modeling of observations from the MCMA-2003 campaign ? Part II: Model application to the CENICA, Pedregal and Santa Ana sites

International audienceA Markov Chain Monte Carlo model for integrating the observations of inorganic species with a thermodynamic equilibrium model was presented in Part I of this series. Using observations taken at three ground sites, i.e. a residential, industrial and rural site, during the MCMA-2003 campaign in Mexico City, the model is used to analyze the inorganic particle and ammonia data and to predict gas phase concentrations of nitric and hydrochloric acid. In general, the model is able to accurately predict the observed inorganic particle concentrations at all three sites. The agreement between the predicted and observed gas phase ammonia concentration is excellent. The NOz concentration calculated from the NOy, NO and NO2 observations is of limited use in constraining the gas phase nitric acid concentration given the large uncertainties in this measure of nitric acid and additional reactive nitrogen species. Focusing on the acidic period of 9?11 April identified by Salcedo et al. (2006), the model accurately predicts the particle phase observations during this period with the exception of the nitrate predictions after 10:00 a.m. (Central Daylight Time, CDT) on 9 April, where the model underpredicts the observations by, on average, 20%. This period had a low planetary boundary layer, very high particle concentrations, and higher than expected nitrogen dioxide concentrations. For periods when the particle chloride observations are consistently above the detection limit, the model is able to both accurately predict the particle chloride mass concentrations and provide well-constrained HCl (g) concentrations. The availability of gas-phase ammonia observations helps constrain the predicted HCl (g) concentrations. When the particles are aqueous, the most likely concentrations of HCl (g) are in the sub-ppbv range. The most likely predicted concentration of HCl (g) was found to reach concentrations of order 10 ppbv if the particles are dry. Finally, the atmospheric relevance of HCl (g) is discussed in terms of its indicator properties for the possible influence of chlorine-mediated photochemistry in Mexico City

6. Peces amazónicos y cambio climático

Con el 15% de todos los peces de agua dulce descritos en el mundo, la cuenca amazónica es el sistema de agua dulce más biodiverso del planeta. Hoy en día, los factores principales de degradación de los ecosistemas de agua dulce en la región amazónica son la rápida expansión de las infraestructuras y actividades económicas. Estas perturbaciones provocan importantes efectos negativos en las comunidades de peces y podrían verse amplificados por los impactos del cambio climático. Las pérdidas de hábitat originados por el cambio climático no deberían tener efectos sobre las tasas de extinción de la especies. Sin embargo, el estrés térmico y la limitación de oxígeno podrían provocar extinciones locales de ciertas especies y producir cambios progresivos en la estructura y composición de las comunidades actuales de peces. Las especies tolerantes al aumento de temperatura, como el Paiche, se expandirán mientras que las especies sensibles a este aumento se reducirán. Cabe destacar que hoy en día las acciones de conservación deben enfocarse en la reducción de los efectos de las amenazas antropogénicas en curso.Avec 15% de tous les poissons d'eau douce décrits dans le monde, le bassin amazonien est le système d'eau douce présentant la plus grande biodiversité de la planète. Aujourd'hui, les principaux facteurs de dégradation des écosystèmes d'eau douce dans la région amazonienne sont l'expansion rapide des infrastructures et les activités économiques. Ces perturbations provoquent d'importants effets négatifs sur les communautés de poissons et pourraient être amplifiés par les impacts du changement climatique. La perte d'habitat due au changement climatique ne devrait avoir aucun effet sur les taux d'extinction des espèces. Cependant, le stress lié à la température et la limitation de l'oxygène pourraient provoquer l'extinction locale de certaines espèces et produire des changements progressifs dans la structure et la composition des communautés actuelles de poissons. Les populations d'espèces tolérantes à l'augmentation de température, comme le Paiche, augmenteront, tandis que les populations d'espèces sensibles à cette augmentation diminueront. Il est important de noter que, à l'heure actuelle, les actions de conservation doivent se concentrer sur la réduction des effets des menaces anthropiques en cours.With 15% of all described freshwater fish in the world, the Amazon basin is the most biodiverse freshwater System of the planet. Nowadays, the main factors of degradation of freshwater ecosystems in the Amazon region are the rapid expansion of infrastructure and economic activities. These disturbances cause negative effects on fish communities and could be amplified by the impacts of climate change. Loss of habitat due to climate change should have no effect on rates of species extinction. However, thermal stress and oxygen limitation could cause local extinctions of certain species and produce Progressive changes in the structure and composition of existing fish communities. Tolerant species to temperature increase -as the Paiche- should expand, while sensitive species should be reduced. It is noteworthy that conservation actions should focus on reducing the effects of anthropogenic threats in progress