Functional characterization of macrophage receptors for in vitro phagocytosis of unopsonized Pseudomonas aeruginosa

The phagocytic receptor for unopsonized Pseudomonas aeruginosa was characterized functionally using human monocyte-derived macrophages. Freshly isolated human peripheral blood monocytes were unable to ingest unopsonized P. aeruginosa; ingestion did not occur until the cells had been in culture for 2 d and it became maximal after 4 d. Macrophages plated on coverslips derivatized with anti-BSA IgG or with human gamma-globulin lost the capacity to phagocytose unopsonized P. aeruginosa, unopsonized zymosan, and EIgG but bound C3bi-coated erythrocytes normally. Each of the four human IgG subclasses and Fc fragments of anti-BSA IgG inhibited phagocytosis of both unopsonized P. aeruginosa and EIgG. Phagocytosis of P. aeruginosa and zymosan was markedly impaired and EIgG minimally inhibited if macrophages were plated on coverslips derivatized with mannan or when mannan was added to the phagocytosis buffer. Phagocytosis of P. aeruginosa and zymosan, and binding of EC3bi was dependent on the presence of divalent cations, but phagocytosis of EIgG was not. The macrophage phagocytic receptor for unopsonized P. aeruginosa was inactivated by proteolytic enzymes. Phagocytosis of P. aeruginosa was inhibited by D-mannose, L-fucose, and alpha methyl mannoside, but not by L-mannose, D-fucose, or D-glucose. The same sugars inhibited phagocytosis of unopsonized zymosan. We conclude that phagocytosis of unopsonized P. aeruginosa by human monocyte-derived macrophages is facilitated by mannose receptors

Secondary anionic phospholipid binding site and gating mechanism in Kir2.1 inward rectifier channels

Inwardly rectifying potassium (Kir) channels regulate multiple tissues. All Kir channels require interaction of phosphatidyl-4,5-bisphosphate (PIP(2)) at a crystallographically identified binding site, but an additional nonspecific secondary anionic phospholipid (PL(−)) is required to generate high PIP(2) sensitivity of Kir2 channel gating. The PL(−)-binding site and mechanism are yet to be elucidated. Here we report docking simulations that identify a putative PL(−)-binding site, adjacent to the PIP(2)-binding site, generated by two lysine residues from neighbouring subunits. When either lysine is mutated to cysteine (K64C and K219C), channel activity is significantly decreased in cells and in reconstituted liposomes. Directly tethering K64C to the membrane by modification with decyl-MTS generates high PIP(2) sensitivity in liposomes, even in the complete absence of PL(−)s. The results provide a coherent molecular mechanism whereby PL(−) interaction with a discrete binding site results in a conformational change that stabilizes the high-affinity PIP(2) activatory site

Sistemas para el suministro de servicios a usuarios de recursos naturales: enfoque, funciones de información y comunicación y consideraciones de política

Hay una creciente aceptación de que no existe un único enfoque para el suministro de servicios rurales que pueda satisfacer las necesidades de todos los usuarios de los recursos naturales. Agrupamos a los usuarios según las siguientes categorías: familias agrícolas con acceso a mercados, comunidades rurales con ingresos derivados de una variedad de actividades, y comunidades con acceso a recursos de propiedad común. Cada grupo tiene necesidades particulares y en muchos casos los sistemas privatizados dejan por fuera aquellos con menos capacidad para relacionarse con los mercados. Exploramos el potencial de sistemas alternativos basado en: el enfoque de sistemas, sistemas de conocimiento, las tecnologías de comunicación e información (TIC) y la comunicación para el desarrollo. Se proyectan tres tipos de entrega de servicios que responden a tres grupos de usuarios de recursos naturales: productores con acceso a mercados, hogares con producción de subsistencia y organizaciones comunitarias. Para cada grupo, se contempla el nivel de análisis y acción y de entrega de servicios, la naturaleza de la información buscada, y las funciones de la comunicación. Una segunda proyección describe los temas de demanda y oferta de TIC para cada grupo. Una tercera proyección aborda la dimensión de planificación estratégica, con énfasis en las características de los resultados e impacto en términos de recursos naturales y de información y comunicación. El artículo concluye con una revisión de aquellos principios que pueden ayudarnos en el diseño de los diferentes sistemas de entrega de servicios que responden a las necesidades de cada grupo de usuarios

Interacción multitáctil en un sistema de generación procedural

Se presentan dos soluciones multitáctiles: para el usuario profesional, banco de trabajo con una superficie de interacción de grandes dimensiones; para el usuario casual, una solución de tamaño reducido, portátil y bajo coste. Se ha desarrollado un pequeño prototipo demo, dentro del área de la generación procedural.De La Re Vega, A. (2009). Interacción multitáctil en un sistema de generación procedural. http://hdl.handle.net/10251/14467Archivo delegad

De novo assembly of red clover transcriptome based on RNA-Seq data provides insight into drought response, gene discovery and marker identification

Background Red clover (Trifolium pratense L.) is a versatile forage crop legume, which can tolerate a variety of soils and is suitable for silage production for winter feed and for grazing. It is one of the most important forage legumes in temperate livestock agriculture. Its beneficial attributes include ability to fix nitrogen, improve soil and provide protein rich animal feed. It is however, a short-lived perennial providing good biomass yield for two or three years. Improved persistency is thus a major breeding target. Better water-stress tolerance is one of the key factors influencing persistency, but little is known about how red clover tolerates water stress. Results Plants from a full sib mapping family were used in a drought experiment, in which the growth rate and relative water content (RWC) identified two pools of ten plants contrasting in their tolerance to drought. Key metabolites were measured and RNA-Seq analysis was carried out on four bulked samples: the two pools sampled before and after drought. Massively parallel sequencing was used to analyse the bulked RNA samples. A de novo transcriptome reconstruction based on the RNA-Seq data was made, resulting in 45181 contigs, representing ‘transcript tags’. These transcript tags were annotated with gene ontology (GO) terms. One of the most striking results from the expression analysis was that the drought sensitive plants were characterised by having approximately twice the number of differentially expressed transcript tags than the tolerant plants after drought. This difference was evident in most of the major GO terms. Before onset of drought the sensitive plants overexpressed a number of genes annotated as senescence-related. Furthermore, the concentration of three metabolites, particularly pinitol, but also proline and malate increased in leaves after drought stress. Conclusions This de novo assembly of a red clover transcriptome from leaf material of droughted and non-droughted plants provides a rich source for gene identification, single nucleotide polymorphisms (SNP) and short sequence repeats (SSR). Comparison of gene expression levels between pools and treatments identified candidate genes for further analysis of the genetic basis of drought tolerance in red clover

Promiscuous targeting of bromodomains by bromosporine identifies BET proteins as master regulators of primary transcription response in leukemia

Bromodomains (BRDs) have emerged as compelling targets for cancer therapy. The development of selective and potent BET (bromo and extra-terminal) inhibitors and their significant activity in diverse tumor models have rapidly translated into clinical studies and have motivated drug development efforts targeting non-BET BRDs. However, the complex multidomain/subunit architecture of BRD protein complexes complicates predictions of the consequences of their pharmacological targeting. To address this issue, we developed a promiscuous BRD inhibitor [bromosporine (BSP)] that broadly targets BRDs (including BETs) with nanomolar affinity, creating a tool for the identification of cellular processes and diseases where BRDs have a regulatory function. As a proof of principle, we studied the effects of BSP on leukemic cell lines known to be sensitive to BET inhibition and found, as expected, strong antiproliferative activity. Comparison of the modulation of transcriptional profiles by BSP after a short exposure to the inhibitor resulted in a BET inhibitor signature but no significant additional changes in transcription that could account for inhibition of other BRDs. Thus, nonselective targeting of BRDs identified BETs, but not other BRDs, as master regulators of context-dependent primary transcription response.The Structural Genomics Consortium is a registered charity (no. 1097737) that receives funds from AbbVie, Bayer Pharma AG, Boehringer Ingelheim, Canada Foundation for Innovation, Eshelman Institute for Innovation, Genome Canada, Innovative Medicines Initiative (EU/EFPIA) (ULTRA-DD grant 115766), Janssen, Merck & Co., Novartis Pharma AG, Ontario Ministry of Economic Development and Innovation, Pfizer, São Paulo Research Foundation (FAPESP), Takeda, and Wellcome Trust (092809/Z/10/Z). P.F., S.P., and C.-Y.W. were supported by a Wellcome Career Development Fellowship (095751/Z/11/Z). A.-C.G. is the Canada Research Chair in Functional Proteomics and the Lea Reichmann Chair in Cancer Proteomics and was supported by the Canadian Institutes of Health Research (foundation grant FDN143301). J.-P.L. was supported by a Cancer Research Society (Canada) Scholarship for the Next Generation of Scientists

Burgeoning Polymer Nano Blends for Improved Controlled Drug Release: A Review

With continual rapid developments in the biomedical field and understanding of the important mechanisms and pharmacokinetics of biological molecules, controlled drug delivery systems (CDDSs) have been at the forefront over conventional drug delivery systems. Over the past several years, scientists have placed boundless energy and time into exploiting a wide variety of excipients, particularly diverse polymers, both natural and synthetic. More recently, the development of nano polymer blends has achieved noteworthy attention due to their amazing properties, such as biocompatibility, biodegradability and more importantly, their pivotal role in controlled and sustained drug release in vitro and in vivo. These compounds come with a number of effective benefits for improving problems of targeted or controlled drug and gene delivery systems; thus, they have been extensively used in medical and pharmaceutical applications. Additionally, they are quite attractive for wound dressings, textiles, tissue engineering, and biomedical prostheses. In this sense, some important and workable natural polymers (namely, chitosan (CS), starch and cellulose) and some applicable synthetic ones (such as poly-lactic-co-glycolic acid (PLGA), poly(lactic acid) (PLA) and poly-glycolic acid (PGA)) have played an indispensable role over the last two decades for their therapeutic effects owing to their appealing and renewable biological properties. According to our data, this is the first review article highlighting CDDSs composed of diverse natural and synthetic nano biopolymers, blended for biological purposes, mostly over the past five years; other reviews have just briefly mentioned the use of such blended polymers. We, additionally, try to make comparisons between various nano blending systems in terms of improved sustained and controlled drug release behavior

Improving neural machine translation for morphologically rich languages

Machine Translation aims to provide a seamless communication and interaction, thereby overcoming human language barriers. Recently, Neural Machine Translation (NMT) approaches have been very successful and achieve state-of-the-art performance in many language pairs. NMT systems consist of millions of neurons that are optimised to learn the input-output mapping between the source and the target languages. However, these systems produce poor translation quality under low-resource conditions and are unable to handle a large vocabulary particularly for languages with rich morphology such as Turkish, Tamil and German. In this project, we present a source vocabulary expansion technique to handle the problem of translating rare and unknown words by incorporating morphological information in the words. The effectiveness of the proposed technique is demonstrated by translating from two morphologically rich languages to English. Using this technique, we achieve a performance gain of approximately 2 BLEU points for both German → English and Turkish → English.Neural Machine Translation (NMT)language pairsneuronsinput-output mappingmorphology2 BLE