Actas del V Congreso de Estudiantes Universitarios de Ciencia, Tecnología e Ingeniería Agronómica

Celebramos ya la quinta edición del Congreso de Estudiantes Universitarios de Ciencia, Tecnología e Ingeniería Agronómica. Año tras año hemos ido incorporando alguna innovación de acuerdo a las sugerencias de los participantes de las diferentes ediciones con el fin de mejorar el desarrollo de cada congreso. Y como habéis observado, este año hemos decidido utilizar las TIC con dos finalidades: para agilizar la organización del mismo y para dar visibilidad a una herramienta docente que esperamos sea de uso rutinario. Este mes de mayo de 2012, presentamos de nuevo el libro de Actas realizado con las aportaciones que los estudiantes y profesores en temas relacionados con las Ciencias Agronómicas nos habéis enviado. Hemos de indicar que observamos una mejora en el cuidado que los participantes ponen a la hora de enviar temas originales, trabajos bien acabados y que cumplen las normas propuestas por el Comité Organizador. Sin embargo, confirmamos que, en alguna medida, siempre son necesarias algunas correcciones y revisiones que esperemos que más que una crítica al trabajo sean recibidas como revisiones constructivas y de mejora del mismo. Dejarlo todo para el último momento, nos hace presentar gráficas o tablas mal referenciadas en el texto, fuentes bibliográficas citadas erróneamente, trabajos de muy baja calidad y alguna que otra falta de ortografía que no se puede permitir en un trabajo universitario. Las prisas nunca fueron buenas y aunque las fechas de inscripción y de entrega de trabajos están al alcance de todos con bastante antelación, al final del proceso de revisión, algún estudiante ha preferido no enviar su trabajo o el comité lo ha rechazado finalmente por su baja calidad. Por eso este año, traemos la frase de Leonardo Da Vinci: “Quien piensa poco, se equivoca mucho” Nos gustaría transmitir a los que van a consultar este libro de Actas que los trabajos incluidos en él no son meros informes de prácticas repetidas, o revisiones bibliográficas superficiales. Podemos decir que este libro es una recopilación de trabajos escritos y revisados con esfuerzo, y cuya finalidad es que pueda ser considerado como un libro de consulta para los futuros estudiantes en esta área de conocimiento. Nuestro agradecimiento a la Fundación Premio Arce, a la Comunidad de Madrid a través del Proyecto NEWGAN (S2009/AGR-1704), a NANTA S.A., The Poultry Research Centre (PRC) Nutreco, Danisco, CEIGRAM, Eumedia, la Editorial Agrícola Española, y la cátedra Fertiberia, como patrocinadores de este evento. Gracias como siempre a todos los profesores, estudiantes, becarios y voluntarios que han colaborado en este V Congreso. Pilar García Rebollar y Mª Ángeles Pérez Caba

Actas del IV Congreso de estudiantes de Ciencia, Tecnología e Ingeniería Agronómica

Se trata de los trabajos presentados por los alumnos en el IV Congreso de estudiantes de Ciencia, Tecnología e Ingeniería Agronómic

Evaluation of the effect of training using auditory stimulation on rhythmic movement in Parkinsonian patients—a combined motor and [18F]-FDG PET study

[Abstract] Introduction: A programme of rehabilitation using auditory cues has previously been shown to decrease movement variability in the gait of Parkinsonian patients. Objective and methods: We studied the temporal variability of finger-tapping and gait in 9 patients with Parkinson's disease (PD) before and after they undertook a physical rehabilitation programme. Positron Emission Tomography (PET) using 2-deoxy-2[18F]fluoro-d-glucose (FDG) was performed in these subjects to look for changes in metabolic brain activity after completion of the rehabilitation program. Results: The reduction of variability was seen not only in gait but also other repetitive movements such as finger tapping. Furthermore, here we show differences in resting regional cerebral glucose utilisation in these patients compared to healthy controls (significant hypometabolism—p<0.001—for the PD group in the right parietal and temporal lobes, left temporal and frontal lobes and a hypermetabolism in the left cerebellum) and specific changes following the improvements in repetitive movement abilities (significant metabolic increment—p<0.001—in the PD group in the right cerebellum and in the right parietal and temporal lobes). Conclusions: Although our study does not allow us to draw firm conclusions, it provides new information on the neural basis of auditory stimulation in PD. Our results extend those from previous studies to show improvement in the temporal variability of two types of rhythmic movements after participation by PD patients in a physical rehabilitation programme, along with changes in glucose uptake in several brain areas involved in sensorimotor processing.Xunta de Galicia; PGIDIT02BTF13701P

Relaciones entre el conocimiento cotidiano y el conocimiento científico: comprendiendo cómo cambia la materia

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RGNNV and SJNNV reassortants produce mortality and replicate in gilthead seabream larvae

Nervous Necrosis Virus (NNV) is one of the most challenging pathogens for aquaculture development nowadays, mainly affecting marine teleost fish of major interest to the aquaculture industry and causing great economic losses. NNV consist in four genotypes, which seem to have a tropism for certain teleost fish species. Among them, gilthead seabream (Sparus aurata) has been considered as a non-susceptible species to the disease produced by traditional NNV genotypes. However, there are some evidences that indicate seabream is able to develop the disease in the presence of certain reassortant strains of NNV, called RGNNV/SJNNV, which possesses the RNA1 segment of the RGNNV genotype and the RNA2 segment of the SJNNV genotype, which may cause a new threat to aquaculture. Therefore, the main objective of this study was to evaluate the susceptibility of gilthead seabream larvae to the reassortant strains RGNNV/SJNNV and SJNNV/RGNNV. For this purpose, larvae were exposed to 104 TCDI50/mL in triplicate tanks with the reassortant strains. Samples of 5 individual larvae were collected at different days post-infection and used for gene expression and infective NNV isolation. Our data show that both reassortants produced mortalities, although the RGNNV/SJNNV was the one which produced the highest mortality and viral gene transcription, which significantly increased from 1 to 7 days post-infection. In conclusion, our study demonstrate that seabream larvae are susceptible to both RGNNV/SJNNV and SJNNV/RGNNV reassortants under laboratory conditions. Further studies should be performed to understand the pathogenicity of the NNV reassortant strains to prevent and control future outbreaks in aquaculture farms

Seasonal variations of the humoral immune parameters of European sea bass (Dicentrarchus labrax L.).

Seasonal cycles, mainly due to great variations in the light duration and temperature, are important and modulate several aspects of the animal behavior. In the case of poikilotherms animals such as fish this is very relevant. Thus, temperature changes fish immunity and affects disease resistance. We evaluate in this work the season variations of the European sea bass (Dicentrarchus labrax) humoral innate parameters focusing on winter months, at which the culture of this specie is more difficult. Our results showed that not all the innate immune parameters are depressed by low temperatures. Moreover, some of them are more dependent than others to the season and both temperature and photoperiod are operating together.Postprint

Molecular identification and characterization of haptoglobin in teleosts revealed an important role on fish viral infections

Haptoglobin (Hp) molecule has been cloned and characterized in two marine teleosts (gilthead seabream and European sea bass), obtaining putative proteins of 319 residues encoded by an ORF of 960 bp in both species. However, the matrix of similarity revealed low identities among bony fish species 78.9% (seabream-sea bass), 43% (seabream/seabass-zebrafish) and lower than 20% with sharks and human. The protein sequences showed a signal peptide from the position 1 to 23, a trypsin domain from 47 to 297, and several predicted disulfide bridges and glycosylation sites. The expression of hp transcript levels during ontogeny showed a progressive increase of expression in seabream whilst remained almost unaltered in sea bass. By tissues, this gene was found constitutively expressed with the highest levels on liver in both species. The main results on hp transcript levels showed the up-regulation in gilthead seabream suffering from naturally occurring lymphocystis disease; and the down-regulation and up-regulation after nodavirus infection in the resistant gilthead seabream and the susceptible European sea bass, respectively. These findings demonstrate for the first time an important role of haptoglobin against viral infections, operating differently in two of the most important marine farmed fish species.Postprint3,26

Fish granzymes and their role in the innate cell-mediated cytotoxicity against nodavirus-infected cells

Granzymes (Gzm) are granule-associated serine proteases, which are important effector molecules in cell-mediated cytotoxicity, classified by its proteolytic activity in: tryptase (GzmA and GzmK), Asp-ase (GzmB), Met-ase (GzmM) or chymase (others). In fish, even at gene level, very few studies have partially identified and characterize them. In this work we have identified the activity of these four granzymes, using colorimetric assays, in leucocytes from gilthead seabream (Sparus aurata) and European sea bass (Dicentrarchus labrax), and how they are increased upon cytotoxic activity against nodavirus-infected tumor cells. The results also showed that GzmA was the most abundant and GzmB the lowest. Deeper characterization of the GzmB led us to identify that seabream leucocytes under cytotoxic response against nodavirus-infected cells showed significantly increased GzmB activity whilst this pattern failed to do so in sea bass leucocytes. Moreover, flow cytometry studies also suggested the presence of GzmB into the cytoplasm of effector cells. At gene level, seabream GzmB gene was found to be up-regulated in leucocytes under cytotoxic activity, mainly if the target cells were infected with nodavirus. These data will through some light in the importance of granzymes in the cytotoxic response of fish and their defense against nodavirus infection