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A DNA vaccine expressing the E2 protein of classical swine fever virus elicits T cell responses that can prime for rapid antibody production and confer total protection upon viral challenge

  • Ganges, L.
  • Barrera, M.
  • Núñez, J. I.
  • Blanco, I.
  • Frias, M. T.
  • Rodríguez, F.
  • Sobrino, F.
Immunization of domestic pigs with a DNA vaccine expressing the complete E2 protein of classical swine fever virus (CSFV) conferred total protection against a severe viral challenge. Immunization with three doses of plasmid pcDNA3.1/E2 elicited a consistent and specific, MHC class II restricted T cell response in the three domestic pigs analyzed, in the absence of detectable anti-CSFV antibodies in serum. Upon challenge specific T cell responses were boosted in the three vaccinated pigs, and a rapid rise in the titers of CSFV neutralizing antibodies was noticed in two of them, which correlated with a total protection. In these two pigs, neither disease symptoms were observed nor was virus detected at any time after CSFV infection. Neutralizing antibody titers were lower in the third vaccine, which developed a mild and transient peak of pyrexia. As expected, similar analyses in three control pigs (injected with the empty vector or PBS) did not reveal the induction of specific T cells or viral antibodies and, upon challenge, animals developed severe symptoms of the disease, including high titers of viremia, hyperthermia and virus spread to different organs. Control pigs developed, also, a marked leucopenia, resulting in SWC3+ (myelomonocytic cells) being the major PBMC population, and a drastic decrease CD3+ T cells. This T cell depletion was prevented in animals immunized with pcDNA3.1/E2. The total protection achieved, in the absence of CSFV antibodies before challenge, supports the relevance in the antiviral response observed of specific T cell responses primed by pcDNA3.1/E2 vaccine, which, upon challenge, led to a rapid induction of neutralizing antibodies. The observation that CSFV antibodies could only be detected in protected animals after viral challenge opens the possibility of exploring the potential of the DNA vaccine approach used to develop marker vaccines against CSF. © 2005 Elsevier Ltd. All rights reserved.

Fast estimation of the calorific values of forest fuels by near-infrared reflectance spectroscopy

  • Gillon, D.
  • Hernando, C.
  • Valette, J. C.
  • Joffre, R.
Fuel calorific value is an important parameter in fire behaviour. The objective of this study is to evaluate the potential of using near-infrared reflectance spectroscopy (NIRS) for determining the calorific value of fuel. Fifty samples of various fuel components from the Mediterranean forest (17.1-24.6 MJ·kg-1) were used to establish a calibration equation between NIR spectra (1100-2500 nm) and calorific value. The coefficient of determination (r2) of the regression between predicted and measured values was 0.92 and the standard error of cross validation was 0.50 MJ·kg-1, i.e.;twice the standard error of the measurement by the conventional method in a bomb calorimeter (0.23 MJ·kg-1). Using this calibration equation, the calorific values of two sets of 15 samples collected weekly during the fire season from two shrub species, Arbutus unedo L.;Erica arborea L.;were predicted. The r2 between NIRS-predicted and measured values were 0.79 and 0.76, respectively, and the standard errors of prediction were 0.36 and 0.21 MJ·kg-1. These results show that NIPS is less accurate than the standard method but it can be used to quickly determine the calorific value of fuels when a large number of measurements are required.

Molecular differentiation between NS1 gene of a field strain Bluetongue virus serotype 2 (BTV-2) and NS1 gene of an attenuated BTV-2 vaccine

  • Agüero, M.
  • Arias, M.
  • Romero, L. J.
  • Zamora, M. J.
  • Sánchez-Vizcaíno, J. M.
At the end of September 2000, clinical symptoms of Bluetongue appeared in sheep flocks of the Balearic Islands (Spain). The presence of the BTV serotype 2 in tissue and blood samples of affected animals was confirmed by laboratory techniques. A systematic vaccination were carried out in affected areas using a live monovalent serotype 2 vaccine available from Onderstepoort laboratory (South Africa). In order to perform epidemiological studies, a new method to differentiate between the NS1 genes of BTV-2 affecting the Balearic islands and that of the Onderstepoort commercial live virus vaccine (monovalent, serotype 2) has been developed. This procedure is based on the use of an RT-PCR, followed by restriction endonuclease analysis. Epidemiological data of a study carried out in the period January-October 2001 using this procedure are included. © 2002 Elsevier Science B.V. All rights reserved.

Haplotype phasing after joint estimation of recombination and linkage disequilibrium in breeding populations

  • Gómez-Raya, L.
  • Hulse, A. M.
  • Thain, D.
  • Rauw, W. M.
A novel method for haplotype phasing in families after joint estimation of recombination fraction and linkage disequilibrium is developed. Results from Monte Carlo computer simulations show that the newly developed E.M. algorithm is accurate if true recombination fraction is 0 even for single families of relatively small sizes. Estimates of recombination fraction and linkage disequilibrium were 0.00 (SD 0.00) and 0.19 (SD 0.03) for simulated recombination fraction and linkage disequilibrium of 0.00 and 0.20, respectively. A genome fragmentation phasing strategy was developed and used for phasing haplotypes in a sire and 36 progeny using the 50 k Illumina BeadChip by a) estimation of the recombination fraction and LD in consecutive SNPs using family information, b) linkage analyses between fragments, c) phasing of haplotypes in parents and progeny and in following generations. Homozygous SNPs in progeny allowed determination of paternal fragment inheritance, and deduction of SNP sequence information of haplotypes from dams. The strategy also allowed detection of genotyping errors. A total of 613 recombination events were detected after linkage analysis was carried out between fragments. Hot and cold spots were identified at the individual (sire level). SNPs for which the sire and calf were heterozygotes became informative (over 90%) after the phasing of haplotypes. Average of regions of identity between half-sibs when comparing its maternal inherited haplotypes (with at least 20 SNP) in common was 0.11 with a maximum of 0.29 and a minimum of 0.05. A Monte-Carlo simulation of BTA1 with the same linkage disequilibrium structure and genetic linkage as the cattle family yielded a 99.98 and 99.94% of correct phases for informative SNPs in sire and calves, respectively. © 2013 Gomez-Raya et al.; licensee BioMed Central Ltd.

Developmental origins of health and disease in swine implications for animal production and biomedical research

  • Gonzalez-Bulnes, A.
  • Astiz, S.
  • Óvilo, C.
  • López-Bote, C. J.
  • Torres-Rovira, L.
  • Barbero, A.
  • Ayuso, M.
  • García-Contreras, C.
  • Vázquez-Gómez, M.
The concept of Developmental Origins of Health and Disease (DOHaD) addresses, from a large set of epidemiological evidences in human beings and translational studies in animal models, both the importance of genetic predisposition and the determinant role of maternal nutrition during pregnancy on adult morphomics and homeostasis. Compelling evidences suggest that both overnutrition and undernutrition may modify the intrauterine environment of the conceptus and may alter the expression of its genome and therefore its phenotype during prenatal and postnatal life. In fact, the DOHaD concept is an extreme shift in the vision of the factors conditioning adult phenotype and supposes a drastic change from a gene-centric perspective, only modified by lifestyle and nutritional strategies during juvenile development and adulthood, to a more holistic approach in which environmental, parental, and prenatal conditions are strongly determining postnatal development and homeostasis. The implications of DOHaD are profound in all the mammalian species and the present review summarizes current knowledge on causes and consequences of DOHaD in pigs, both for meat production and as a well-recognized model for biomedicine research. � 2016 Elsevier Inc.

Lignin-carbohydrate network in wood and pulps A determinant for reactivity

  • Henriksson, G.
  • Lawoko, M.
  • Eugenio Martin, M. E.
  • Gellerstedt, G.
Pretreatment of wood or kraft pulp with endoglucanase followed by swelling in urea leaves a non-crystalline residue that can be dissolved in strong aqueous sodium hydroxide-sodium borate solution. A stepwise precipitation process employing acid and barium ions can separate lignin-carbohydrate complexes enriched in individual polysaccharides. This procedure has been applied to eucalypt and birch wood and to the corresponding kraft pulps. Thioacidolysis of the various lignin-carbohydrate complexes was used as the major analytical technique to obtain information about the structure and structural changes in lignin. A combination of thioacidolysis and size exclusion chromatography was used to obtain knowledge on the degree of depolymerisation and repolymerisation of lignin when going from wood to chemical pulp. In contrast to spruce wood and kraft pulp, complete recovery of the lignin-carbohydrate complexes could not be obtained from hardwood samples. © 2007 by Walter de Gruyter.

Low temperature induces the accumulation of alcohol dehydrogenase mRNA in Arabidopsis thaliana, a chilling-tolerant plant

  • Jarillo, J. A.
  • Leyva, A.
  • Salinas, J.
  • Martínez-Zapater, J. M.
mRNA encoding alcohol dehydrogenase (ADH) increases in etiolated seedlings and leaves of Arabidopsis thaliana (L.) Heynh. upon exposure to low temperature. The analysis of this response after water stress and abscisic acid (ABA) treatments in Arabidopsis wild type and ABA-deficient and -insensitive mutants indicates that cold accumulation of ADH mRNA could be induced by both anaerobic metabolism and increase of ABA concentration resulting from low temperature exposure. By using one Arabidopsis ADH null mutant, we show that ADH activity is not required for successful development of freezing tolerance in this species.

Specific and sensitive primers for the detection of predated olive fruit flies, Bactrocera oleae (Diptera Tephritidae)

  • Lantero, E.
  • Matallanas, B.
  • Ochando, M. D.
  • Pascual, S.
  • Callejas, C.
Bactrocera oleae, the olive fruit fly, is a major pest of olive (Olea europaea L.) trees worldwide. Its presence can cause important losses, with consequences for the economies of countries that produce and export table olives and olive oil. Efforts to control olive fruit fly populations have, however, been insufficient. Now more than ever, environmentally friendly alternatives need to be considered in potential control programs. Generalist predators could provide a way of managing this pest naturally. However, the identification of candidate predator species is essential if such a management system is to be introduced. The present paper describes a set of species-specific primers for detecting the presence of B.oleae DNA in the gut of predatory arthropods. All primers were tested for checking cross-reactive amplification of other fruit fly DNA and evaluated in hetero specific mixes of nucleic acids. All were found to be very sensitive for B. oleae. Subsequent feeding trials were conducted using one of the most abundant species of ground dwelling carabids in olive groves in south-eastern Madrid, Spain. These trials allowed determining that 253F-334R and 334F-253R primer pairs had the highest detection efficiency with an ID50 of around 78h. These primers therefore provide a very useful tool for screening the gut contents of potential predators of B. oleae, and can thus reveal candidate species for the pest's biological control. © 2017 INIA.

Comparative analysis of muscle transcriptome between pig genotypes identifies genes and regulatory mechanisms associated to growth, fatness and metabolism

  • Ayuso, M.
  • Fernández, A.
  • Núñez, Y.
  • Benítez, R.
  • Isabel, B.
  • Barragán, C.
  • Fernández, A. I.
  • Rey, A. I.
  • Medrano, J. F.
  • Cánovas, Á, González-Bulnes, A.
  • López-Bote, C.
  • Óvilo, C.
Iberian ham production includes both purebred (IB) and Duroc-crossbred (IBxDU) Iberian pigs, which show important differences in meat quality and production traits, such as muscle growth and fatness. This experiment was conducted to investigate gene expression differences, transcriptional regulation and genetic polymorphisms that could be associated with the observed phenotypic differences between IB and IBxDU pigs. Nine IB and 10 IBxDU pigs were slaughtered at birth. Morphometric measures and blood samples were obtained and samples from Biceps femoris muscle were employed for compositional and transcriptome analysis by RNA-Seq technology. Phenotypic differences were evident at this early age, including greater body size and weight in IBxDU and greater Biceps femoris intramuscular fat and plasma cholesterol content in IB newborns. We detected 149 differentially expressed genes between IB and IBxDU neonates (p < 0.01 and Fold-Change > 1. 5). Several were related to adipose and muscle tissues development (DLK1, FGF21 or UBC). The functional interpretation of the transcriptomic differences revealed enrichment of functions and pathways related to lipid metabolism in IB and to cellular and muscle growth in IBxDU pigs. Protein catabolism, cholesterol biosynthesis and immune system were functions enriched in both genotypes. We identified transcription factors potentially affecting the observed gene expression differences. Some of them have known functions on adipogenesis (CEBPA, EGRs), lipid metabolism (PPARGC1B) and myogenesis (FOXOs, MEF2D, MYOD1), which suggest a key role in the meat quality differences existing between IB and IBxDU hams. We also identified several polymorphisms showing differential segregation between IB and IBxDU pigs. Among them, non-synonymous variants were detected in several transcription factors as PPARGC1B and TRIM63 genes, which could be associated to altered gene function. Taken together, these results provide information about candidate genes, metabolic pathways and genetic polymorphisms potentially involved in phenotypic differences between IB and IBxDU pigs associated to meat quality and production traits.

The potentiation effect makes the difference Non-toxic concentrations of ZnO nanoparticles enhance Cu nanoparticle toxicity in vitro

  • Li, L.
  • Fernández-Cruz, M. L.
  • Connolly, M.
  • Conde, E.
  • Fernández, M.
  • Schuster, M.
  • Navas, J. M.
Here we examined whether the addition of a non-toxic concentration (6.25. μg/mL) of zinc oxide nanoparticles (ZnONPs 19, 35 and 57. nm, respectively) modulates the cytotoxicity of copper nanoparticles (CuNPs, 63. nm in size) in the human hepatoma cell line HepG2. The cytotoxic effect of CuNPs on HepG2 cells was markedly enhanced by the ZnONPs, the largest ZnONPs causing the highest increase in toxicity. However, CuNPs cytotoxicity was not affected by co-incubation with medium containing only zinc ions, indicating the increase in toxicity might be attributed to the particle form of ZnONPs. Transmission electron microscopy (TEM) revealed the presence of CuNPs and ZnONPs inside the cells co-exposed to both types of NP and outflow of cytoplasm through the damaged cell membrane. Inductively coupled plasma mass spectrometry (ICP-MS) determined an increase in the concentration of zinc and a decrease in that of copper in co-exposed cells. On the basis of these results, we propose that accumulation of large numbers of ZnONPs in the cells alters cellular membranes and the cytotoxicity of CuNPs is increased. © 2014 Elsevier B.V.

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