Lethal iron deprivation induced by non-neutralizing antibodies targeting transferrin receptor 1 in malignant B cells

A number of antibodies have been developed that induce lethal iron deprivation (LID) by targeting the transferrin receptor 1 (TfR1/CD71) and either neutralizing transferrin (Tf) binding, blocking internalization of the receptor and/or inducing its degradation. We have developed recombinant antibodies targeting human TfR1 (ch128.1 and ch128.1Av), which induce receptor degradation and are cytotoxic to certain malignant B-cells. We now show that internalization of TfR1 bound to these antibodies can lead to its sequestration and degradation, as well as reduced Tf uptake, and the induction of a transcriptional response consistent with iron deprivation, which is mediated in part by downstream targets of p53. Cells resistant to these antibodies do not sequester and degrade TfR1 after internalization of the antibody/receptor complex, and accordingly maintain their ability to internalize Tf. These findings are expected to facilitate the rational design and clinical use of therapeutic agents targeting iron import via TfR1 in hematopoietic malignancies.Fil: Rodríguez, José A.. University of California at Los Angeles; Estados UnidosFil: Luria Pérez, Rosendo. University of California at Los Angeles; Estados Unidos. Hospital infantil de México “Federico Gómez”; MéxicoFil: López Valdés, Héctor E.. University of California at Los Angeles; Estados UnidosFil: Casero, David. University of California at Los Angeles; Estados UnidosFil: Daniels, Tracy R.. University of California at Los Angeles; Estados UnidosFil: Patel, Shabnum. University of California at Los Angeles; Estados UnidosFil: Avila, David. University of California at Los Angeles; Estados UnidosFil: Leuchter, Richard. University of California at Los Angeles; Estados UnidosFil: So, Sokuntheavy. University of California at Los Angeles; Estados UnidosFil: Ortiz Sánchez, Elizabeth. University of California at Los Angeles; Estados UnidosFil: Bonavida, Benjamin. University of California at Los Angeles; Estados UnidosFil: Martínez Maza, Otoniel. University of California at Los Angeles; Estados UnidosFil: Charles, Andrew C.. University of California at Los Angeles; Estados UnidosFil: Pellegrini, Matteo. University of California at Los Angeles; Estados UnidosFil: Helguera, Gustavo Fernando. University of California at Los Angeles; Estados Unidos. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay; ArgentinaFil: Penichet, Manuel L.. University of California at Los Angeles; Estados Unido

Study of deposition parameters for the fabrication of ZnO thin films using femtosecond laser

Femtosecond (fs) pulsed laser deposition (fs-PLD) of ZnO thin film on borosilicate glass substrates is reported in this work. The effect of important fs-PLD parameters such as target–substrate distance, laser pulse energy and substrate temperature on structure, morphology, optical transparency and luminescence of as-deposited films is discussed. XRD analysis reveals that all the films grown using the laser energy range 120–230 μJ are polycrystalline when they are deposited at room temperature in a ~10−5 Torr vacuum. Introducing 0.7 mTorr oxygen pressure, the films show preferred c-axis growth and transform into a single-crystal-like film when the substrate temperature is increased to 100 °C. The scanning electron micrographs show the presence of small nano-size grains at 25 °C, which grow in size to the regular hexagonal shape particles at 100 °C. Optical transmission of the ZnO film is found to increase with an increase in crystal quality. Maximum transmittance of 95 % in the wavelength range 400–1400 nm is achieved for films deposited at 100 °C employing a laser pulse energy of 180 μJ. The luminescence spectra show a strong UV emission band peaked at 377 nm close to the ZnO band gap. The shallow donor defects increase at higher pulse energies and higher substrate temperatures, which give rise to violet-blue luminescence. The results indicate that nano-crystalline ZnO thin films with high crystalline quality and optical transparency can be fabricated by using pulses from fs lasers

Pressure effects during pulsed-laser deposition of barium titanate thin films

The composition and homogeneity of barium titanate films grown by pulsed-laser deposition at different substrate temperatures (room temperature, 700°C) and gas environments (O2, Ar) in a broad pressure range (10-7-1 mbar) are correlated to the plasma expansion dynamics. It is found that the deposited films present an excess of Ba in the intermediate pressure range (10-2 < P < 10-1 mbar) and a peaked distribution of Ba to Ti atoms ratio, that is not related to either the substrate temperature or the nature of the gas environment. The results are discussed in terms of the dependence of the plume length (LP) on the gas pressure and the existence of scattering processes for distances (d) from the target lower than LP and the diffusion of the ejected species for LP < d. © Springer-Verlag 1998.This work was partially supported by CICYT (Spain) under TIC 96-0467 and the CNRS (France) GDR No 86.Peer Reviewe

Pressure effects during pulsed-laser deposition of barium titanate thin films

The composition and homogeneity of barium titanate films grown by pulsed-laser deposition at different substrate temperatures (room temperature, 700°C) and gas environments (O2, Ar) in a broad pressure range (10-7-1 mbar) are correlated to the plasma expansion dynamics. It is found that the deposited films present an excess of Ba in the intermediate pressure range (10-2 < P < 10-1 mbar) and a peaked distribution of Ba to Ti atoms ratio, that is not related to either the substrate temperature or the nature of the gas environment. The results are discussed in terms of the dependence of the plume length (LP) on the gas pressure and the existence of scattering processes for distances (d) from the target lower than LP and the diffusion of the ejected species for LP < d. © Springer-Verlag 1998.This work was partially supported by CICYT (Spain) under TIC 96-0467 and the CNRS (France) GDR No 86.Peer Reviewe

Structural impact of chromium incorporation in as-grown and flash-lamp-annealed sputter deposited titanium oxide films

We address the impact of chromium (Cr) incorporation (<15 at.%) in the structure of titanium dioxide (TiO:Cr) films for as-grown and after flash-lamp-annealing (FLA) states. Samples were produced by DC magnetron sputtering on either unheated or heated (400 °C) substrates. Complementary medium- and local-order information was extracted by X-ray diffraction and absorption near-edge structure, respectively. TiO:Cr grown on unheated substrates are amorphous with the major contribution from Cr and progressive formation of Cr with Cr. On heated substrates, anatase phase is dominant for low Cr levels (≤7 at.%) and the structure evolves with Cr towards a disordered mixed-oxide with rutile structure. By tuning the FLA energy density, customized (single or mixed) phase formation is achieved from (initially amorphous) Cr-free TiO. For amorphous TiO:Cr with low Cr (≤7 at.%), FLA induces a short-range rutile structure but structural ordering is not observed at higher Cr levels. Nonetheless, FLA annihilates Cr sites and promotes Cr, which is associated to the mixed-oxide rutile. FLA also improves the pristine structure of anatase TiO:Cr grown on heated substrates. These results provide relevant information about the atomic structure of mixed oxides and the use of FLA for the synthesis of band-gap engineered TiO-based materials.Financial support from grant P2013/MIT-2775 (Comunidad Autónoma de Madrid, Spain) is greatly acknowledged. The research leading to these results has received funding from the European Community's Seventh Framework Programme (FP7/2007–2013) under grant agreement n° 226716

Current status and future developments of the ion beam facility at the centre of micro-analysis of materials in Madrid

16 pags., 6 figs.We report on the current status of the ion beam laboratory of the Centre of Micro-Analysis of Materials at the Autonomous University of Madrid. The 5 MV accelerator facility provides MeV ion beams of any stable element. Six main beam lines are under operation, allowing the analysis and modification of materials through ion beam methods. Although the most demanded ions are H and He for standard Rutherford backscattering spectrometry and particle-induced X-ray emission experiments, many other analytical techniques and specific set-ups are available for users. The facility especially highlights for the use of high-energy heavy ions and microbeams, with important applications in material science, optics and electronics, biology, cultural heritage, and astrophysics. Ongoing upgrades of the facility are oriented to improve the quality of the service for external users and to face new scientific and technological challenges in areas such as advanced materials, space, energy and health.We acknowledge funding from EU COST action CA17126, national projects ENE2016-80788-05-2-R, CTQ-2017-84309-C2-2-R, FPA2017-87568-P, and PID2019-104390BG-I00, PID2019-105156GB-I00, and local projects S2017/BMD-3888, TransNanoAvansens (P2018/NMT4349), TechnofusionIII (S2018/EMT4437) from Comunidad Autónoma de Madrid. ARC acknowledges Ramón y Cajal program under contract RYC-2015-18047

Adsorción de plaguicidas organofosforados por óxido grafítico

A study on the distribution of the mineral nutrients in the different parts of rose bush was carried out with the aim of chossing whichever of these might be most suitable as diagnostic tissue, the cultivar used being "Gabriela". Although for some nutrients (such as N, K) the leaf position on the stem does not seem to have a great effect on its foliar concentrations, in other cases (Ca, Mn, Cu) these concentrations vary widely according to the situation of the leaf. In general, the greatest concentration variations are noted in the youngest leaves, the maximum stability being shown by the first two leaves of 5 leaflets. This stabiliry of the mineral nutrient concentrations in these first two leaves of 5 leaflets makes suitable as samples for diagnostic purposes.Peer reviewe