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Loading plasmid DNA into poly(ester) microparticles usually involves the formation of a multiple emulsion, using homogenisation techniques such as sonication or Ultra-Turrax®. These procedures may negatively affect the integrity of the macromolecule and consequently its activity. The aim of this study was to prepare and evaluate DNA-loaded microparticles by TROMS (Total Recirculation One-Machine System), a new procedure that is based on the formation of a multiple emulsion by the injection of the phases under a turbulent regime. Microparticles were prepared with either Resomer® RG 502 (MP 502) or RG 756 (MP 756) and DNA loading was quantified fluorimetrically. DNA loading in MP 756 was almost twice as high as in MP 502 (510 vs. 285 ng/mg, respectively). Under both formulations, the loaded plasmid was released while maintaining its integrity for at least 24 days (MP 502) and 40 days (MP 756). Finally, the transfection efficiency was studied after injection of the microparticles (MP 502) into rat skeletal muscle and compared with naked DNA injection. Injection of naked DNA (150 μg DNA per muscle) achieved higher but variable expression levels that decreased after 3 weeks. In contrast, the muscles injected with microparticles (6.8 μg DNA per muscle) showed lower but homogeneous expression values, which were maintained for at least 3 weeks. [Copyright &y& Elsevier]

An objective method for inductively modelling the distribution of mountain land units using GIS managed topographic variables is presented. The landscape of a small high mountain catchment in the Spanish Pyrenees, covered with grassland, was classified in ten land units by hierarchical agglomerative clustering, using a sample of 194 random plots, in which classes of vegetation, soils and landforms were defined. Additionally, seven layers of topographic variables (altitude, slope angle, aspect, solar radiation, topographic wetness index, specificcatchment area, and regolith thickness) were created from a Digital Elevation Model. The affinity of each land unit to the topographic variables was calculated using Binary Discriminant Analysis (BDA), after dichotomising the latter around their mean values. Then, the distribution of each land unit was predicted by boolean operations combining step by step distributions for the seven topographic variables ordered, for each unit, after the absolute values of the Haberman's residuals in BDA. The predicted distributions were tested (chi2) against that of the observed sampling plots. From the original ten land units, the distributions of eight of them were successfully predicted (four are related to the slope sequence, two reflect the water accumulation in the soil, and two respond to geomorphic processes) while the remaining two had to be rejected. Part of the catchment (39%)was not assigned to any land unit, probably because more distributedvariables accounting for snow distribution are necessary. [ABSTRACT FROM AUTHOR]

Distribution area and surface are both parameters of paramount importance for habitat management, monitoring and conservation. Here we present the distribution of eight zonal forest types of mainland Spain that are consistent with the Habitat Types (HT) listed in Annex I of the European Union Habitats Directive 92/43 EC. Their dominant species and HT codes are Fagus sylvatica (9120, 9130 and 9150), Quercus robur and Q. pyrenaica (9230), Q. suber (9330), Pinus uncinata (9430), P. nigra ssp. salzmannii (9530) and P. pinea (subset of 9540). These distributions are based on tesserae from the 1:50,000 Spanish Forest Map and are the result of sorting assisted by supplementary databases. The distributions are presented as vector coverages, and provide three information levels of increasing detail: geographic distribution, basic forest type and structural forest patch. Two R scripts are also included with the dataset. They implement a segmented regression approach to investigate forest fragmentation on these or other patch-like data., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships which have, or could be perceived to have, influenced the work reported in this article., (© 2020 The Author(s).)

This work illustrates the application of a simulation model to analyse how swiftly large-scale land-use changes can drive broad territories to collapse. In this sense, the economic needs of a population should not clash with the natural environment but rather be reconciled with it. Abundant literature deals with the integration of socioeconomic drivers, ecological aspects, farming management, and climatology related to Algerian rangeland degradation. The present study seeks to compare the time course of Alfa grass biomass and the livestock raised on these distinctive rangelands under two different land-use strategies. The traditional one has nomads as the main inhabitants of these lands. For centuries, their strategy for alleviating pressure on resources was to move from one area to other. The more recent sedentary land-use leads to overgrazing supported by the massive use of cheap supplemental feed. Additionally, the model was used as a platform to launch scenarios for sustainable land-use management under a competitive market-economy. A key finding for preserving grazing resources was the increment of supplemental feed prices, which is compatible with stocking rates higher than the historical ones., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Mitigation strategies are crucial for desertification given that once degradation starts, other solutions are extremely expensive or unworkable. Prevention is key to handle this problem and solutions should be based on spotting and deactivating the stressors of the system. Following this topic, the Spanish Plan of Action to Combat Desertification (SPACD) created the basis for implementing two innovative approaches to evaluate the threat of land degradation in the country. This paper presents tools for preventing desertification in the form of a geomatic approach to enable the periodic assessments of the status and trends of land condition. Also System Dynamics modelling has been used to integrate bio-physical and socio-economic aspects of desertification to explain and analyse degradation in the main hot spots detected in Spain. The 2dRUE procedure was implemented to map the land-condition status by comparing potential land productivity according to water availability, the limiting factor in arid lands, with plant-biomass data. This assessment showed that 20% of the territory is degraded and an additional 1% is actively degrading. System Dynamics modelling was applied to study the five desertification landscapes identified by the SPACD. The risk analysis, implemented on these models, concluded that 'Herbaceous crops affected by soil erosion' is the landscape most at risk, while the Plackett-Burman sensitivity analysis used to rank the factors highlighted the supremacy of climatic factors above socioeconomic drivers., (Copyright © 2016 Elsevier B.V. All rights reserved.)

The mechanisms of calicivirus attachment and internalization are not well understood, mainly due to the lack of a reliable cell-culture system for most of its members. In this study, rabbit vesivirus (RaV) virions were shown to bind annexin A2 (ANXA2) in a membrane protein fraction from HEK293T cells, using a virus overlay protein-binding assay and matrix-assisted laser desorption/ionization time-of-flight analysis. A monoclonal anti-ANXA2 antibody and small interfering RNA-mediated knockdown of ANXA2 expression in HEK293T cells reduced virus infection significantly, further supporting the role of ANXA2 in RaV attachment and/or internalization.

The Herpesviridae includes at least eight viral species pathogenic for humans, responsible for a wide variety of clinical symptoms. The lack of an effective vaccine and the moderate to high toxicity of the available synthetic anti-herpes compounds emphasises the need for new inhibitors. Several Phyllanthus genus (Euphorbiaceae) members have been widely used in traditional medicine and their biological properties have been intensely studied. In this study we investigated the in vitro antiviral activity of the Cuban-endemic plant Phyllanthus orbicularis H.B.K. against Herpes simplex virus type 1 (HSV-1) and 2 (HSV-2) reference strains and clinical isolates with different sensitivities to acyclovir. The inhibitory activity on Human cytomegalovirus (HCMV) replication was also investigated. The selectivity indexes (SI) found for Ph. orbicularis aqueous extract ranged from 8.7 to 37.6. Studies on the antiviral mechanisms involved revealed that the drug acted at early stages of herpesvirus replication, possibly by producing a virucidal effect, although further inhibition of intracellular replication events could not be ruled out.

Rabbit vesivirus infection induces membrane modifications and accumulation of vesicular structures in the cytoplasm of infected Vero cells. Crude RaV replication complexes (RCs) have been purified and their structural and functional properties have been characterized. We show that calnexin, an ER-resident protein, RaV non-structural proteins 2AB-, 2C-, 3A-, 3B- and 3CD-like as well as viral RNAs co-localize within membranous structures which are able to replicate the endogenous RNA templates. The purified virus factories protected their viral RNA contents from microccocal nuclease degradation and were inaccessible to exogenously added synthetic transcripts. In addition, we have shown that RCs can be used to investigate uridylylation of native endogenous VPg. In contrast to the observation that the virus factories were inaccessible to RNAs, RCs were accessible to added recombinant VPg which was subsequently nucleotidylylated. Nevertheless no elongation of an RNA chain attached to native or recombinant VPg could be demonstrated.

This report describes the isolation, cDNA cloning, complete genome nucleotide sequence, and partial characterization of a new cultivable calicivirus isolated from juvenile feeder European rabbits (Oryctolagus cuniculus) showing symptoms of diarrhea. Absence of neutralization by type-specific neutralizing antibodies for 40 caliciviruses and phylogenetic sequence comparisons of the open reading frame 1-encoded polyprotein with those of other caliciviruses demonstrate that this new calicivirus is a putative novel member of the Vesivirus genus which is closely related to the marine calicivirus subgroup. According to its putative classification, this new virus has been named rabbit vesivirus.

We have prepared and characterised injectable adenovirus-loaded polymeric microparticles to be used for in vitro and in vivo gene transfer studies. Microparticles were prepared by the water-in-oil-in-water solvent evaporation method using a novel system where the emulsification process is carried out by the turbulent injection of the phases in the total recirculation one-machine system (TROMS) apparatus. In vitro studies were performed to assess the amount of infectious adenovirus released from the microparticles, showing that these microparticles release higher amounts of infectious adenovirus than microparticles prepared by standard emulsification techniques. We also tested whether sustained release in vivo could overcome the short-lived gene expression profile which is typical of adenovirus delivery into muscle. Intramuscular injection of adenovirus-loaded microparticles in immunocompetent mice showed transgene (beta-galactosidase) expression for at least 7 weeks in two out of four muscles injected with adenovirus-loaded microparticles prepared by TROMS, but not in control muscles injected with purified adenovirus stocks.

The antiviral and cytotoxic activity of Phyllanthus orbicularis, a member of the Euphorbiaceae, was evaluated in tissue culture. An aqueous extract made from leaves and stems of this plant exhibited selective antiviral indexes of 12.3 and 26 against bovine herpesvirus type 1 and herpes simplex virus type 2, respectively, showing no selective antiviral activity against adenovirus type 5 and mengovirus. Incubation with this plant extract during cell culture infection, impaired the productive replication of both herpes viruses in an extract concentration-dependent manner, also depending on the multiplicity of infection (MOI) used. The results obtained suggested that the P. orbicularis antiviral activity might be partially due to a direct interaction with virus particles or their entry into the cell, instead of interfering with intracellular virus-specific macromolecular synthesis.

The aim of this study was to test the suitability of "pattern analysis" for the exploration of data provided by computer-assisted semen analysis methods. Data sets derived from the examination of boar sperm responses to bicarbonate and caffeine (measurements on 3208 spermatozoa) and from studies of semen cryopreservation in Mohor gazelles (7278 spermatozoa) were reanalyzed. A nonhierarchical classification method was used to generate initial subgroups of spermatozoa (9 for boar, 13 for gazelle). The subgroup centroids were fused, yielding three boar sperm subpopulations and four gazelle sperm subpopulations distinguished by sperm behaviors. Bicarbonate and caffeine both induced major transitions (p < 0.0001) of boar sperm behavior, detected as shifts in group membership (from group 2, i.e., active but nonlinear movement, into group 1, i.e., linear, rapid movement). Some spermatozoa (approximately 3%) were refractory to both caffeine and bicarbonate. The gazelle sperm subpopulation structure was affected by the inclusion of equex (sodium triethanolamine lauryl sulfate) in the cryoprotective diluents. Equex suppressed the appearance of spermatozoa with erratic behavior (p < 0.0001; high curvilinear velocity, low linearity, low straight-line velocity) after cryopreservation. The proportion of these erratic spermatozoa was positively correlated with animal age (r = 0.68, p = 0.029). Pattern analysis revealed novel aspects of the data not seen in the original investigations and usefully supplemented the more standard data analysis approaches.