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Epitope specificity determines cross-protection of a SIT-induced IgG4 antibody

  • Gadermaier, E.
  • James, L.K.
  • Shamji, M.H.
  • Blatt, K.
  • Fauland, K.
  • Zieglmayer, P.
  • Garmatiuk, T.
  • Focke-Tejkl, M.
  • Villalba Díaz, Mayte
  • Beavil, R.
  • Keller, W.
  • Valent, P.
  • Durham, S.R.
  • Gould, H.J.
  • Flicker, S.
  • Valenta, R.
The calcium-binding 2EF-hand protein Phl p 7 from timothy grass pollen is a highly cross-reactive pollen pan-allergen that can induce severe clinical symptoms in allergic patients. Recently, a human monoclonal Phl p 7-specific IgG4 antibody (mAb102.1F10) was isolated from a patient who had received grass pollen-specific immunotherapy (SIT).We studied epitope specificity, cross-reactivity, affinity and cross-protection of mAb102.1F10 towards homologous calcium-binding pollen allergens. Sequence comparisons and molecular modelling studies were performed with ClustalW and SPADE, respectively. Surface plasmon resonance measurements were done with purified recombinant allergens. Binding and cross-reactivity of patients’ IgE and mAb102.1F10 to calcium-binding allergens and peptides thereof was studied with quantitative RAST-based methods, in ELISA, basophil activation and IgE-facilitated allergen presentation experiments. Allergens from Timothy grass (Phl p 7), Alder (Aln g 4), Birch (Bet v 4), Turnip rape (Bra r 1), Lamb′s quarter (Che a 3) and Olive (Ole e 3, Ole e 8) showed high sequence similarity and cross-reacted with allergic patients’ IgE. mAb102.1F10 bound the C-terminal portion of Phl p 7 in a calcium-dependent manner. It cross-reacted with high affinity with Ole e 3 whereas binding and affinity to the other allergens was low. mAb102.1F10 showed limited inhibition of patients’ IgE binding and basophil activation. Sequence comparison and surface exposure calculations identified three amino acids likely to be responsible for limited cross-reactivity.Our results demonstrate that a small number of amino acid differences among cross-reactive allergens can reduce the affinity of binding by a SIT-induced IgG and thus limit cross-protection.

Characterization of Profilin and Polcalcin Panallergens From Ash Pollen

  • Mas García, Salvador
  • Garrido Arandia, María
  • Batanero Cremades, Eva
  • Purohit, A.
  • Pauli, G.
  • Rodríguez García, Rosalía
  • Barderas Manchado, Rodrigo
  • Villalba Díaz, Mayte
Background: Ash (Fraxinus excelsior) is an important source of allergenic pollen in temperate areas of Europe. Profilin and polcalcin are 2 important panallergens involved in cross-reactivity between different sources. Objective: To clone and produce Fra e 2 (profilin) and Fra e 3 (polcalcin) as recombinant proteins and evaluate their immunological properties using the natural forms obtained from ash pollen. Methods: Total RNA from ash pollen was used as a template to obtain the specific complementary DNA (cDNA) sequences of the 2 panallergens. The cDNA-encoding sequences were cloned into the pET11b expression vector and used to transform BL21 (DE3) Escherichia coli cells. Proteins were expressed, purified by chromatography, and characterized structurally by circular dichroism, mass spectrometry, and immunologically by western blot and ELISA using profilin and polcalcin polyclonal antibodies and human sera from ash pollen–sensitized patients. Results: Profilin and polcalcin amino acid sequences from ash pollen showed a high degree of identity with homologous allergens from different sources. The cDNA-encoding allergen sequences were expressed as nonfusion recombinant proteins and purified to homogeneity. Secondary structure values were similar to those obtained from other members of these families. Allergenic Properties of the recombinant allergens were observed to be equivalent to those of the natural counterparts of F excelsior pollen.Conclusions: Fra e 2 and Fra e 3 recombinant allergens might be used in clinical diagnosis to determine profilin- and polcalcin-specific IgE levels present in the sera of ash pollen–sensitized patients, thus facilitating the finding of the sensitizing source in areas with complex sensitization profiles.

Some differences between the Great Depression and the Recent Crisis: learning a lesson

  • Fernández Díaz, Andres
In this paper we try to point out the lost opportunity on how to address the current crisis, forgetting principles and theories that were successfully applied in the Great Depression. After some considerations about the Stock Market Crash that began on October 24, 1929 and their catastrophic consequences, we analyze the reaction of European authorities to the present crisis, highlighting the financial costs and the loss of welfare that has led to the rescue of peripheral Eurozone countries. Our analysis is based on the interpretation in the framework of the present time of the work and thought of John Maynard Keynes. In this comparative analysis we find a strong contrast between the economic policy outlined in those times by our honorable English economist, and the presence of a recalcitrant single thought and the reductionist determinism that have characterized the economic policies bring about in the crisis years in our country and, in general, in the Eurozone area, given rise to an avoidable situation of austerity and recession we have suffered between 2008 and 2013. In the article we stand out the fact that the Great Depression was harsher and more terrible that the Financial Crisis of these last years, but it was better managed by the American Authorities, otherwise happening with the crisis that we are undergoing.

The Allergenic Structure of the Thaumatinlike Protein Ole e 13 Is Degraded by Processing of Raw Olive Fruits

  • Torres, M.
  • Alvarez García, Elvira
  • Bartra, J.
  • Alcántara, M.
  • Palomares Gracia, Oscar
  • Villalba Díaz, Mayte
  • Rodríguez García, Rosalía
Background: The thaumatin-like protein (TLP) Ole e 13 in raw olive fruit is responsible for occupational allergy in olive oil mill workers. However,these workers do not experience allergic symptoms after ingestion of edible olive.Objectives: To analyze the presence of IgE-reactive TLP in raw and edible olive fruit and to assess the allergenic potency of both sources.Methods: The content of TLP in raw and edible olive fruit protein extracts was analyzed using immunoblotting with sera from allergic patients and with olive TLP–specific IgG. The structural and immunological stability of TLP were assayed using immunoblotting after treatment of both raw olive and purified TLP with 0.25 M NaOH solution for 24 hours. Olive pollen extract was investigated by immunoblotting for TLP content. Results: The TLP contained in raw olive fruit was not present in edible olives as a result of maceration before human consumption. No TLP was detected in olive pollen using specific IgG or sera from patients allergic to olive fruit. Sera from patients allergic to olive pollen did not react with purified TLP. Conclusions: IgE-reactive TLP is not present in edible olive, thus explaining the low number of patients allergic to this highly consumed fruit. Patients allergic to olive pollen are not sensitized to TLP and, therefore, not expected to be at risk of food allergy to olive fruit or TLP plant sources

Restauración de un conjunto de documentos de los siglos XVII, XVIII Y XIX encuadernados:(signatura BH MSS 1346)

  • Alonso Pallarés, Blanca
  • Latorre Vázquez, Inmaculada
En adelante se exponen los trabajos realizados para la restauración del ejemplar. Parte de la restauración sirvió de Trabajo de Fin de Grado de la Escuela Superior de Conservación y Restauración de Bienes Culturales de Madrid para Blanca Alonso, finalizando el tratamiento Inmaculada Latorre.Se trata de un volumen particular al hallarse soportes y técnicas muy diferentes por el amplio espectro temporal de los documentos.

CALIFA, the Calar Alto Legacy Integral Field Area survey III. Second public data release

  • Castillo Morales, África
  • Gil de Paz, Armando
  • Catalán Torrecilla, Cristina
This paper describes the Second Public Data Release (DR2) of the Calar Alto Legacy Integral Field Area (CALIFA) survey. The data for 200 objects are made public, including the 100 galaxies of the First Public Data Release (DR1). Data were obtained with the integral-field spectrograph PMAS /PPak mounted on the 3.5 m telescope at the Calar Alto observatory. Two different spectral setups are available for each galaxy, (i) a low-resolution V500 setup covering the wavelength range 3745-7500 Å with a spectral resolution of 6.0 Å (FWHM); and (ii) a medium-resolution V1200 setup covering the wavelength range 3650-4840 Å with a spectral resolution of 2.3 Å (FWHM). The sample covers a redshift range between 0.005 and 0.03, with a wide range of properties in the color-magnitude diagram, stellar mass, ionization conditions, and morphological types. All the cubes in the data release were reduced with the latest pipeline, which includes improved spectrophotometric calibration, spatial registration, and spatial resolution. The spectrophotometric calibration is better than 6% and the median spatial resolution is 2´´ 4. In total, the second data release contains over 1.5 million spectra.

Analysis of combined radial velocities and activity of BD+20 1790: evidence supporting the existence of a planetary companion

  • Hernán Obispo, M.
  • Castro Rubio, Elisa de
  • Cornide Castro-Piñeiro, Manuel
Context. In a previous paper we reported a planetary companion to the young and very active K5Ve star BD+20 1790. We found that this star has a high level of stellar activity (log R'_HK = -3.7) that manifests in a plethora of phenomena (starspots, prominences, plages, large flares). Based on a careful study of these activity features and a deep discussion and analysis of the effects of the stellar activity on the radial velocity measurements, we demonstrated that the presence of a planet provided the best explanation for the radial velocity variations and all the peculiarities of this star. The orbital solution resulted in a close-in massive planet with a period of 7.78 days. However, a paper by Figueira et al. (2010, A&A, 513, L8) questioned the evidence for the planetary companion. Aims. This paper aims to more rigorously assess the nature of the radial velocity measurements with an expanded data set and new methods of analysis. Methods. We have employed Bayesian methods to simultaneously analyse the radial velocity and activity measurements based on a combined data set that includes new and previously published observations. Results. We conclude that the Bayesian analysis and the new activity study support the presence of a planetary companion to BD+20 1790. A new orbital solution is presented, after removing the two main contributions of stellar jitter, one that varies with the photometric period (2.8 days) and another that varies with the synodic period of the star-planet system (4.36 days). We present a new method to determine these jitter components, considering them as second and third signals in the system. A discussion on possible star-planet interaction is included, based on the Bayesian analysis of the activity indices, which indicates that they modulate with the synodic period. We propose two different sources for flare events in this system: one related to the geometry of the system and the relative movement of the star and planet, and a second one purely stochastic source that is related to the evolution of stellar surface active regions. Also, we observe for the first time the magnetic field of the star, from spectropolarimetric data.

CARMENES input catalogue of M dwarfs I. Low-resolution spectroscopy with CAFOS

  • Alonso Floriano, F. J.
  • Morales, J. C.
  • Caballero, J. A.
  • Montes Gutiérrez, David
  • Klutsch, A.
  • Mundt, R.
  • Cortés Contreras, Miriam
  • Ribas, I.
  • Reiners, A.
  • Amado, P. J.
  • Quirrenbach, A.
  • Jeffers, S. V.
Context. CARMENES is a stabilised, high-resolution, double-channel spectrograph at the 3.5m Calar Alto telescope. It is optimally designed for radial-velocity surveys of M dwarfs with potentially habitable Earth-mass planets. Aims. We prepare a list of the brightest, single M dwarfs in each spectral subtype observable from the northern hemisphere, from which we will select the best planet-hunting targets for CARMENES. Methods. In this first paper on the preparation of our input catalogue, we compiled a large amount of public data and collected low-resolution optical spectroscopy with CAFOS at the 2.2m Calar Alto telescope for 753 stars. We derived accurate spectral types using a dense grid of standard stars, a double least-squares minimisation technique, and 31 spectral indices previously defined by other authors. Additionally, we quantified surface gravity, metallicity, and chromospheric activity for all the stars in our sample. Results. We calculated spectral types for all 753 stars, of which 305 are new and 448 are revised. We measured pseudo-equivalent widths of H α for all the stars in our sample, concluded that chromospheric activity does not affect spectral typing from our indices, and tabulated 49 stars that had been reported to be young stars in open clusters, moving groups, and stellar associations. Of the 753 stars, two are new subdwarf candidates, three are T Tauri stars, 25 are giants, 44 are K dwarfs, and 679 are M dwarfs. Many of the 261 investigated dwarfs in the range M4.0-8.0V are among the brightest stars known in their spectral subtype. Conclusions. This collection of low-resolution spectroscopic data serves as a candidate target list for the CARMENES survey and can be highly valuable for other radial-velocity surveys of M dwarfs and for studies of cool dwarfs in the solar neighbourhood.

Bar pattern speeds in CALIFA galaxies I. Fast bars across the Hubble sequence

  • Marino, Raffaella Anna
Context. The bar pattern speed (Ω_b) is defined as the rotational frequency of the bar, and it determines the bar dynamics. Several methods have been proposed for measuring Ω_b. The non-parametric method proposed by Tremaine & Weinberg (1984, ApJ, 282, L5; TW) and based on stellar kinematics is the most accurate. This method has been applied so far to 17 galaxies, most of them SB0 and SBa types. Aims. We have applied the TW method to a new sample of 15 strong and bright barred galaxies, spanning a wide range of morphological types from SB0 to SBbc. Combining our analysis with previous studies, we investigate 32 barred galaxies with their pattern speed measured by the TW method. The resulting total sample of barred galaxies allows us to study the dependence of Ω_b on galaxy properties, such as the Hubble type. Methods. We measured Ω_b using the TW method on the stellar velocity maps provided by the integral-field spectroscopy data from the CALIFA survey. Integral-field data solve the problems that long-slit data present when applying the TW method, resulting in the determination of more accurate Ω_b. In addition, we have also derived the ratio R of the corotation radius to the bar length of the galaxies. According to this parameter, bars can be classified as fast (R < 1.4) and slow (R > 1.4). Results. For all the galaxies, R is compatible within the errors with fast bars. We cannot rule out (at 95% level) the fast bar solution for any galaxy. We have not observed any significant trend between R and the galaxy morphological type. Conclusions. Our results indicate that independent of the Hubble type, bars have been formed and then evolve as fast rotators. This observational result will constrain the scenarios of formation and evolution of bars proposed by numerical simulations.

Star-formation histories of local luminous infrared galaxies

  • Pereira Santaella, Miguel
  • Alonso Herrero, Almudena
  • Colina, Luis
  • Miralles Caballero, Daniel
  • Pérez González, Pablo Guillermo
  • Arribas, Santiago
  • Bellocchi, Enrica
  • Cazzoli, Sara
  • Diaz Santos, Tanio
  • Piqueras López, Javier
We present analysis of the integrated spectral energy distribution (SED) from the ultraviolet (UV) to the far-infrared and H alpha of a sample of 29 local systems and individual galaxies with infrared (IR) luminosities between 10^11 L_⨀and 10^11.8 L_⨀. We combined new narrow-band Hα + [NII] and broad-band g, r optical imaging taken with the Nordic Optical Telescope (NOT), with archival GALEX, 2MASS, Spitzer, and Herschel data. Their SEDs (photometry and integrated Hα flux) were fitted simultaneously with a modified version of the MAGPHYS code using stellar population synthesis models for the UV-near-IR range and thermal emission models for the IR emission taking the energy balance between the absorbed and re-emitted radiation into account. From the SED fits, we derive the star-formation histories (SFH) of these galaxies. For nearly half of them, the star-formation rate appears to be approximately constant during the last few Gyr. In the other half, the current star-formation rate seems to be enhanced by a factor of 3-20 with respect to what occurred ∼1 Gyr ago. Objects with constant SFH tend to be more massive than starbursts, and they are compatible with the expected properties of a main-sequence (M-S) galaxy. Likewise, the derived SFHs show that all our objects were M-S galaxies ∼1 Gyr ago with stellar masses between 10^10.1 and 10^11.5 M_⨀. We also derived the average extinction (A_v = 0.6-3 mag) and the polycyclic aromatic hydrocarbon luminosity to L_IR ratio (0.03-0.16) from our fits. We combined the A_v with the total IR and Hα luminosities into a diagram that can be used to identify objects with rapidly changing (increasing or decreasing) SFR during the past 100 Myr.

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