Effect of graphene substrate on the SERS Spectra of Aromatic bifunctional molecules on metal nanoparticles

The design of molecular sensors plays a very important role within nanotechnology and especially in the development of different devices for biomedical applications. Biosensors can be classified according to various criteria such as the type of interaction established between the recognition element and the analyte or the type of signal detection from the analyte (transduction). When Raman spectroscopy is used as an optical transduction technique the variations in the Raman signal due to the physical or chemical interaction between the analyte and the recognition element has to be detected. Therefore any significant improvement in the amplification of the optical sensor signal represents a breakthrough in the design of molecular sensors. In this sense, Surface-Enhanced Raman Spectroscopy (SERS) involves an enormous enhancement of the Raman signal from a molecule in the vicinity of a metal surface. The main objective of this work is to evaluate the effect of a monolayer of graphene oxide (GO) on the distribution of metal nanoparticles (NPs) and on the global SERS enhancement of paminothiophenol (pATP) and 4-mercaptobenzoic acid (4MBA) adsorbed on this substrate. These aromatic bifunctional molecules are able to interact to metal NPs and also they offer the possibility to link with biomolecules. Additionally by decorating Au or Ag NPs on graphene sheets, a coupled EM effect caused by the aggregation of the NPs and strong electronic interactions between Au or Ag NPs and the graphene sheets are considered to be responsible for the significantly enhanced Raman signal of the analytes [1-2]. Since there are increasing needs for methods to conduct reproducible and sensitive Raman measurements, Grapheneenhanced Raman Scattering (GERS) is emerging as an important method [3].Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

X-ray emission from stellar jets by collision against high-density molecular clouds: an application to HH 248

We investigate the plausibility of detecting X-ray emission from a stellar jet that impacts against a dense molecular cloud. This scenario may be usual for classical T Tauri stars with jets in dense star-forming complexes. We first model the impact of a jet against a dense cloud by 2D axisymmetric hydrodynamic simulations, exploring different configurations of the ambient environment. Then, we compare our results with XMM-Newton observations of the Herbig-Haro object HH 248, where extended X-ray emission aligned with the optical knots is detected at the edge of the nearby IC 434 cloud. Our simulations show that a jet can produce plasma with temperatures up to 10 MK, consistent with production of X-ray emission, after impacting a dense cloud. We find that jets denser than the ambient medium but less dense than the cloud produce detectable X-ray emission only at the impact onto the cloud. From the exploration of the model parameter space, we constrain the physical conditions (jet density and velocity, cloud density) that reproduce well the intrinsic luminosity and emission measure of the X-ray source possibly associated with HH 248. Thus, we suggest that the extended X-ray source close to HH 248 corresponds to the jet impacting on a dense cloud.Comment: Accepted for publication in ApJ. (12 pages, 12 figures

Desarrollo y evaluación de una vacuna DNA contra el virus de la enfermedad de linfocistis (LCDV)

El virus de la enfermedad de linfocistis (LCDV) infecta tanto a peces marinos como dulceacuícolas, produciendo una patología que supone un grave problema para la acuicultura debido a las pérdidas económicas asociadas a su alta morbilidad. En el presente estudio se ha desarrollado un plásmido recombinante con objeto de ser utilizado como vacuna DNA para limitar la incidencia de dicha enfermedad en el cultivo de dorada (Sparus aurata). Para ello, se clonó el ORF de la proteína principal de la cápside (MCP) del LCDV de dorada (LCDV-Sa) en el plásmido de expresión pcDNA3.1/NT-GFP-TOPO, y se utilizó para transfectar la línea celular de dorada SAF-1. Los resultados muestran la correcta expresión del plásmido vacunal en estas células mediante la detección de GFP por microscopía de fluorescencia e inmunodetección de la MCP viral. Posteriormente, se realizó un experimento de vacunación por inyección intramuscular (0,15 µg/g pez) en doradas juveniles, estudiándose la distribución y expresión del plásmido vacunal. Los análisis de PCR y RT-PCR realizados muestran que la vacuna se distribuye de forma sistémica, expresándose en los diferentes tejidos analizados. También se evaluó la protección conferida por la vacuna frente a la infección por LCDV inyectado intraperitonealmente (105 TCID50/g pez) a los 21 d post-vacunación, analizándose la presencia de genoma viral a los 10 d post-inoculación en peces vacunados y controles. Sólo se detectó el genoma viral en los grupos controles, demostrándose así que existe una protección frente a la infección por LCDV en los peces vacunados.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Real time plasma disruptions detection in JET implemented with the ITMS platform using FPGA based IDAQ

The use of FPGAs in data acquisition cards for processing purposes allows an efficient real time pattern recognition algorithm implementation. Using 13 JETs database waveforms an algorithm for detecting incoming plasma disruptions has been implemented. This algorithm is written in MATLAB using floating point representation. In this work we show the methodology used to implement the real time version of the algorithm using Intelligent Data Acquisition Cards (IDAQ), DAQ devices with field programmable gate array (FPGA) for local processing. This methodology is based on the translation of the MATLAB code to LabVIEW and the final coding of specific pieces of code in LabVIEW for FPGA in fixed point format. The whole system for evaluating the real time disruption detection (RTDD) has been implemented using the Intelligent Test and Measurement System (ITMS) platform. ITMS offers distributed data acquisition, distribution and real time processing capabilities with advanced, but easy to use, software tools that simplify application development and system setup. The RTDD implementation uses a standard PXI/PXIe architecture. Two 8 channel analog output cards play JETs database signals, two 8 channel DAQ with FPGA acquire signals and computes a feature vector based in FFT analysis. Finally the vector acquired is used by the system CPU to execute a pattern recognition algorithm to estimate an incoming disruption

Evaluation of immune response after LCDV-Sa infection in DNA-vaccinated gilthead seabream

The immune-related gene expression in vaccinated gilthead seabream after Lymphocystis Disease Virus 3 (LCDV-Sa) infection was analysed by using an OpenArray based on TaqMan qPCR. The DNA vaccine used in this study encodes the viral major capsid protein and confers protection against LCDV-Sa infection in juvenile gilthead seabream. Gilthead seabream juveniles were distributed into four experimental groups and intramuscularly injected with the vaccine (vaccinated group), the empty-plasmid (mock-vaccinated group), or PBS (control groups). Thirty days after vaccination, vaccinated and mock-vaccinated fish, as well as one of the control groups, were injected intraperitoneally with LCDV-Sa (106 TCID50/fish). Samples of head-kidney (HK) from 6 fish were individually collected 1 and 3 days post-infection (dpi). The relative expression levels of 49 genes related to the immune response and 4 reference genes were analysed using an OpenArray. Samples from the non-infected control group were used as calibrator. The number of genes differentially expressed (DEG) in HK at 1 dpi was higher in vaccinated fish compared with both mock-vaccinated and non-vaccinated animals. At 3 dpi, most DEG were upregulated, and the differences in their number among groups were minimized. The recombination-activating gene 1 (rag1), a mediator of development of B and T lymphocytes, was the only gene upregulated in HK samples at 1 dpi. This gene was also upregulated in non-vaccinated animals but at 3 dpi. In contrast, early mx induction was observed in non-vaccinated animals (upregulation of mx2 at 1 dpi) in comparison to vaccinated seabreams (upregulation of mx1 and mx2 at 3 dpi). The results that will be discussed could evidence the role of the DNA vaccine as regulator of the primary lymphoid tissues (HK) in gilthead seabream against LCDV-Sa infection, through downregulation of inflammation related-genes, early upregulation of rag1, and a later expression of interferon stimulated genes.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tec

A shiny app for modeling the lifetime in primary breast cancer patients through phase-type distributions

Phase-type distributions (PHDs), which are defined as the distribution of the lifetime up to the absorption in an absorbent Markov chain, are an appropriate candidate to model the lifetime of any system, since any non-negative probability distribution can be approximated by a PHD with sufficient precision. Despite PHD potential, friendly statistical programs do not have a module implemented in their interfaces to handle PHD. Thus, researchers must consider others statistical software such as R, Matlab or Python that work with the compilation of code chunks and functions. This fact might be an important handicap for those researchers who do not have sufficient knowledge in programming environments. In this paper, a new interactive web application developed with shiny is introduced in order to adjust PHD to an experimental dataset. This open access app does not require any kind of knowledge about programming or major mathematical concepts. Users can easily compare the graphic fit of several PHDs while estimating their parameters and assess the goodness of fit with just several clicks. All these functionalities are exhibited by means of a numerical simulation and modeling the time to live since the diagnostic in primary breast cancer patients

Immune response of vaccinated juvenile gilthead seabream (Sparus aurata) after LCDV-Sa infection

Lymphocystis disease is one of the main viral pathologies affecting cultured gilthead seabream in the Mediterranean area. In our group, a DNA-vaccine has been developed based on the major capsid protein (MCP) of the Lymphocystis Disease Virus 3 (LCDV-Sa). The aim of the present study is the evaluation of immune-related gene expression in vaccinated fish after viral infection to identify immunogenes involved in the vaccine-induced protection. To fulfil this objective an OpenArray® platform has been developed to study 49 genes related to the immune response. Reference and viral genes were also evaluated. Gilthead seabream specimens (5 g mean weight) were distributed into 3 experimental groups, inoculated with the vaccine at 0.1 µg/g fish dose, the empty plasmid at the same dose or PBS. Thirty days post-vaccination, fish were intramuscularly injected with the virus at 106 TCID50/fish dose. Samples of head-kidney, spleen, intestine and caudal fin from 6 fish were individually collected at 1, 2 and 3-days post-injection in all groups. The quantification of viral DNA in fins of fish challenged with LCDV-Sa were carried out by a qPCR assay targeting a viral structural gene (putative myristoylated membrane protein, MMP) alternative to the mcp gene contained in the vaccine. The results obtained showed an increase of genes deregulated within the haematopoietic organs between vaccinated and non-vaccinated fish. However, in the intestine and fin, the results showed the opposite trend. The global effect of fish vaccination was a diminished immune response compared to non-vaccinated fish, being 83 and 99 genes differentially expressed through the experiment, respectively. Moreover, viral replication decreased in groups of fish previously vaccinated. The modulation of the immune response provoked by the vaccination trial seems to control the progression of the disease.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tec

Desarrollo de una vacuna DNA para el control de la enfermedad de linfocistis

Leiva, R., Borrego, J.J., Castro, D. y Labella, A.M. 2018. Desarrollo de una vacuna DNA para el control de la enfermedad de linfocistis. En: La Acuicultura en el Litoral Suratlántico. IX Jornadas de Acuicultura en el Litroral Suratlántico, p 96. Instituto de Investigación y Formación Agraria y Pesquera (IFAPA), Consejería de Agricultura, Pesca y Desarrollo Rural, Junta de Andalucía.El virus de la enfermedad de linfocistis (LCDV) es el agente etiológico de la enfermedad de linfocistis, que afecta tanto a peces marinos como dulceacuícolas. Esta enfermedad supone un grave problema para el sector de la acuicultura, provocando pérdidas económicas debido a su alta morbilidad. En el presente estudio se ha desarrollado un plásmido recombinante con objeto de ser utilizado como vacuna de DNA para limitar la incidencia de dicha enfermedad en el cultivo de dorada (Sparus aurata). El gen codificante de la proteína principal de la cápside (MCP) del LCDV de dorada (LCDV-Sa) se clonó en primer lugar en el vector de expresión pGEX-6P-3, con el fin de expresar la MCP viral como proteína de fusión con GST (glutathione S-transferase) en Escherichia coli BL-21. La expresión de la proteína de fusión MCP-GST en células bacterianas se comprobó mediante Western blot e inmunoensayo dot-blot con anticuerpos específicos dirigidos contra la MCP y la GST. Esta MCP recombinante se empleará como antígeno de captura para la detección mediante ELISA de anticuerpos anti-LCDV en peces vacunados. Por otra parte, el gen codificante de la MCP se subclonó en el vector de expresión pcDNA3.1/NT-GFP-TOPO, obteniéndose así el plásmido vacunal. Tras su amplificación en E. coli TOP 10, el plásmido se purificó y se utilizó para transfectar la línea celular de dorada SAF-1, evaluándose dos métodos de transfección: Nucleofector Kit y lipofectamina. La expresión de la MCP viral en células SAF-1 transfectadas con el plásmido vacunal se ha demostrado mediante detección de la GFP (green fluorescent protein) por microscopía de epifluorescencia, y por inmunodetección de la MCP viral utilizando anticuerpos específicos. El plásmido vacunal obtenido se inyectará intramuscularmente en ejemplares de dorada para determinar la distribución y expresión temporal de la vacuna, así como para detectar anticuerpos anti-LCDV en los peces vacunados.Proyecto de Excelencia de la Junta de Andalucía (P12-RNM-2261). Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech