FT-IR spectroscopy study of the reaction of obtention of hybrid materials

[ES] Se han preparado materiales híbridos por medio de reacciones de hidrólisis y condensación de alcóxidos de Si y Ti (TEOS y TBT, respectivamente) y de reacciones de copolimerización de éstos con polidimetilsiloxano (PDMS). Se han estudiado las citadas reacciones mediante espectroscopia FT-IR, desde el mismo comienzo hasta la obtención del material final. La hidrólisis del TEOS así como la autocondensación del os grupos Si-OH generados tanto para formar cadenas entrecruzadas como lineales se han seguido mediante las bandas situadas a 880, 1180 y 1150 cm-1, respectivamente. La policondensación de dichos grupos con PDMS se ha seguido por la banda a 850 cm-1. Por otro lado, la hidrólisis del TBT y la autocondensación de grupos Ti-OH se han seguido por la banda situada a 1130 y por la variación de la absorbancia en la región espectral 770-510 cm-1, respectivamente. La formación de enlaces Si-O-Ti por condensación de grupos Si-OH y Ti-OH se ha seguido mediante la banda a 936 cm-1. Los resultados obtenidos han mostrado que las reacciones de hidrólisis y policondensación dependen de la concentración de TBT en el medio de reacción. La formación de estructuras entrecruzadas de enlaces Si-O-Si se ve favorecida por el TBT, si bien por el contrario éste impide la reacción de copolimerización TEOS-PDMS. La autocondensación de grupos Si-OH y Ti-OH es muy rápida dando lugar a enlaces Si-O-Si y Ti-O-Ti, respectivamente. También se forman enlaces Si-O-Ti en los comienzos de la reacción, sin embargo éstos tienden a desaparecer en el transcurso de la misma. Finalmente se ha estudiado la variación de la concentración de cadenas cíclicas y lineales de PDMS durante toda la reacción.[EN] Hybrid materials have been prepared in this work through the reactions of Si and Ti alkoxides (TEOS and TBT, respectively) and polydimethil siloxane (PDMS). These reactions have been studied by means of FT-IR spectroscopy during the whole reaction time. The hydrolysis of TEOS molecule has been followed by the 880 cm-1 band, and the self-condensation reactions through the 1180 and 1150 cm-1 bands. Polycondesation reaction between Si-OH groups and PDMS molecules has been followed by the 850 cm-1 band. On the other hand, the hydrolysis reaction of TBT and the self-condensation of Ti-OH groups have been followed by the 1130 and 770-510 cm-1 bands, respectively. Finally the condensation reaction between Si-OH and Ti-OH groups have been studied by the 936 cm-1 band. Results have shown that hydrolysis and condensation reactions are depending on TBT concentration. The formation of Si-O-Si cross-linked structures increases with the TBT concentrations in the reaction. The selfcondensation reaction of Si-OH grups or Ti-OH grous is very reapid forming Si-O-Si and Ti-O-Ti bonds, respectively. However, the Si-O-Ti bonds which are formed during the first moments of reaction are also rapidly broken due to H2O molecules or the reaction medium. The evolution of PDMS linear and cyclic molecules is also studied.Este trabajo ha sido realizado de acuerdo a un Proyecto de Investigación del MCYT correspondiente al Plan Nacional y cuya referencia es MAT2002-03891. Lucía Téllez quiere agradecer al Instituto Politécnico Nacional y al Consejo Nacional de Ciencia y Tecnología de México (CONACyT) la ayuda prestada de acuerdo con la beca de referencia 72432.Peer reviewe

Role of New Functional MRI Techniques in the Diagnosis, Staging, and Followup of Gynecological Cancer: Comparison with PET-CT

Recent developments in diagnostic imaging techniques have magnified the role and potential of both MRI and PET-CT in female pelvic imaging. This article reviews the techniques and clinical applications of new functional MRI (fMRI) including diffusion-weighted MRI (DWI), dynamic contrast-enhanced (DCE)-MRI, comparing with PET-CT. These new emerging provide not only anatomic but also functional imaging, allowing detection of small volumes of active tumor at diagnosis and early disease relapse, which may not result in detectable morphological changes at conventional imaging. This information is useful in distinguishing between recurrent/residual tumor and post-treatment changes and assessing treatment response, with a clear impact on patient management. Both PET-CT and now fMRI have proved to be very valuable tools for evaluation of gynecologic tumors. Most papers try to compare these techniques, but in our experience both are complementary in management of these patients. Meanwhile PET-CT is superior in diagnosis of ganglionar disease; fMRI presents higher accuracy in local preoperative staging. Both techniques can be used as biomarkers of tumor response and present high accuracy in diagnosis of local recurrence and peritoneal dissemination, with complementary roles depending on histological type, anatomic location and tumoral volume

Cloud point extraction and ICP-MS for titanium speciation in water samples

An analytical method for the separation and determination of titanium dioxide nanoparticles in water samples has been developed. The separation was performed by Cloud Point Extraction (CPE) with Triton X-114. Titanium dioxide nanoparticles and ionic titanium were analysed in the surfactant rich phase and surfactant poor phase respectively, by inductively coupled plasma-mass spectrometry (ICP-MS). Parameters related to the CPE procedure such as Triton X-114 and NaCl concentrations were evaluated. Optimum concentrations of 0.03% (w/v) and 2.5 mM of Triton X-114 and NaCl respectively, were selected to develop this study. The TiO2 nanoparticles extracted were digested using HNO3 and H2O2 in an ultrasonic bath for 10 min at 60°C and analysed by ICP-MS. The analytical characteristics of the method (calibration, limits of detection and quantification, precision and recovery) were evaluated. The LOD and LOQ for Ti determination in the surfactant rich phase were 0.13 and 0.45 µg L−1, respectively. Finally, the method was applied for the determination of TiO2 nanoparticles in swimming pool water samplesThe authors wish to thank the Spanish Ministerio de Ciencia, Innovación y Universidades (Project number RTI2018-099222-B-100), the European Union (programme Interreg Atlantic Area, Project number EAPA_590/2018), and Xunta de Galicia (Grupo de Referencia Competitiva ED431C2018/19 for financial support. This research was partially supported by the Consellería de Educación Program for the Development of Strategic Grouping in Materials - AEMAT at the University of Santiago de Compostela under grant No. ED431E2018/08, Xunta de Galicia. These programs are co-funded by FEDER (UE).S

Chemoselectivity on the synthesis of iridacycles: A theoretical and experimental study

The selective synthesis of a spirobifluorene-iridacyclopentadiene complex has been achieved through the corresponding methoxyalkenylcarbeneiridium complex. The chemoselectivity of the Csingle bondH bond activation over the precursor has been studied via DFT calculations on the relative energies of the E and Z isomers of several examples and compared with experimental results. The data suggest that the steric effect of the substituents has more influence than their electronic character on the structure of the resulting iridacycle compounds.Xunta de Galicia | Ref. ED431F 2016/005Xunta de Galicia | Ref. GRC2015/017Unión Europea-FEDER (Interreg V-A—España-Portugal) | Ref. 0245_IBEROS_1_

Museo virtual de la neurociencia

Memoria ID-0154. Ayudas de la Universidad de Salamanca para la innovación docente, curso 2015-2016

Spirobifluorene metallaaromatics

Spirobifluorene derivatives find use in many end-user applications. Therefore, further expansion of their scope is the focus of many research studies. However, although the optical properties of spirobifluorenes can be greatly tuned through incorporation of metal complexes, to date, spirobifluorene metallaaromatics remain unknown. Taking advantage of the versatility of our methodology for the synthesis of metallaaromatic systems, this work reports the first metallaaromatic spirobifluorene compound. The presence of an Ir atom was found to redshift the absorption maximum by ca. 1.1 eV compared to bare spirobifluorene. Additionally, X-ray analysis as well as anisotropy of the current-induced density calculations revealed this compound to be of aromatic nature. The high stability in solution, solid state, under air, and at high temperature, as well as distinct optical properties of this new class of compounds are expected to open new frontiers for chiroptical and optoelectronic applications.Xunta de Galicia | Ref. ED431F 2016/005Unión Europea-FEDER (Interreg V-A—España-Portugal) | Ref. 0245_IBEROS_1_EXunta de Galicia | Ref. GRC2015/01

Optical and electrochemical properties of spirobifluorene iridanaphthalene complexes

Three new spirobifluorene iridaaromatic compounds bearing electron-withdrawing or electron-donor substituents or another iridanaphthalene moiety have been synthesized and structurally characterized. Thorough experimental and theoretical evaluation revealed that these novel systems present a high thermal, air and electrochemical stability as well as low optical and electronic energy gap values with a significant redshift of the absorption maximum in the UV-Vis spectra and predicted remarkably higher first hyperpolarizabilities compared to their organic counterparts. Therefore, the combination of a metallaaromatic system with a spirobifluorene moiety leads to the design and development of new spirobifluorene derivatives. These new systems have shown interesting optical and electronic properties making them of interest for future applications in optoelectronics.Xunta de Galicia | Ref. GRC2019/2

Metabolic clustering analysis as a strategy for compound selection in the drug discovery pipeline for leishmaniasis

A lack of viable hits, increasing resistance, and limited knowledge on mode of action is hindering drug discovery for many diseases. To optimize prioritization and accelerate the discovery process, a strategy to cluster compounds based on more than chemical structure is required. We show the power of metabolomics in comparing effects on metabolism of 28 different candidate treatments for Leishmaniasis (25 from the GSK Leishmania box, two analogues of Leishmania box series, and amphotericin B as a gold standard treatment), tested in the axenic amastigote form of Leishmania donovani. Capillary electrophoresis–mass spectrometry was applied to identify the metabolic profile of Leishmania donovani, and principal components analysis was used to cluster compounds on potential mode of action, offering a medium throughput screening approach in drug selection/prioritization. The comprehensive and sensitive nature of the data has also made detailed effects of each compound obtainable, providing a resource to assist in further mechanistic studies and prioritization of these compounds for the development of new antileishmanial drugs

Endothelial Progenitor Cells: Relevant Players in the Vasculopathy and Lung Fibrosis Associated with the Presence of Interstitial Lung Disease in Systemic Sclerosis Patients

Endothelial progenitor cells (EPC), which are key effectors in the physiologic vascular network, have been described as relevant players in autoimmune diseases. We previously showed that EPC frequency may help to identify the presence of interstitial lung disease (ILD) in rheumatoid arthritis patients. Given that ILD constitutes the main cause of mortality in systemic sclerosis (SSc) patients, we aimed to determine the EPC contribution to the pathogenic processes of vasculopathy and lung fibrosis in SSc-ILD+. EPC quantification was performed by flow cytometry on blood from 83 individuals: 21 SSc-ILD+ patients and subjects from comparative groups (20 SSc-ILD- and 21 idiopathic pulmonary fibrosis (IPF) patients and 21 healthy controls (HC)). EPC were considered as CD34+, CD45low, CD309+, and CD133+. A significant increase in EPC frequency was found in SSc-ILD+ patients when compared to HC (p < 0.001). SSc-ILD+ patients exhibited a higher EPC frequency than SSc-ILD- patients (p = 0.012), whereas it was markedly reduced compared to IPF patients (p < 0.001). EPC frequency was higher in males (p = 0.04) and negatively correlated to SSc duration (p = 0.04) in SSc-ILD+ patients. Our results indicate a role of EPC in the processes of vasculopathy and lung fibrosis in SSc-ILD+. EPC frequency may be considered as a biomarker of ILD in SSc patients.V.P.-C. is supported by a pre-doctoral grant from IDIVAL [PREVAL 18/01]. S.R.-M. is supported by funds from the RETICS Program [RD16/0012/0009, Instituto de Salud Carlos III (ISCIII), co-funded by the European Regional Development Fund (ERDF)]. B.A.-M. is a recipient of a ‘López Albo’ Post-Residency Programme funded by Servicio Cántabro de Salud. L.L.-G. is supported by funds from INNVAL20/06 (IDIVAL). R.P.-F. is supported by funds from the START project [FOREUM18/34]. O.G. is staff personnel of Xunta de Galicia (Servizo Galego de Saude (SERGAS) through a research-staff stabilization contract (ISCIII/SERGAS), and his work is funded by ISCIII and the ERDF [grants RD16/0012/0014 (RIER) and PI17/00409]. He is a beneficiary of project funds from the Research Executive Agency (REA) of the European Union in the framework of MSCA-RISE Action of the H2020 Programme, project 734899—Olive-Net. R.L.-M. is a recipient of a Miguel Servet type I fellowship [ISCIII, co-funded by the European Social Fund, ‘Investing in your future’, CP16/00033]

Endothelial Progenitor Cells as a Potential Biomarker in Interstitial Lung Disease Associated with Rheumatoid Arthritis

Interstitial lung disease (ILD) increases morbidity and mortality in patients with rheumatoid arthritis (RA). Although the pathogenesis of ILD associated with RA (RA-ILD+) remains poorly defined, vascular tissue is crucial in lung physiology. In this context, endothelial progenitor cells (EPC) are involved in endothelial tissue repair. However, little is known about their implication in RA-ILD+. Accordingly, we aimed to investigate the potential role of EPC related to endothelial damage in RA-ILD+. EPC quantification in peripheral blood from 80 individuals (20 RA-ILD+ patients, 25 RA-ILD? patients, 21 idiopathic pulmonary fibrosis (IPF) patients, and 14 healthy controls) was performed by flow cytometry. EPC were considered as CD34+, CD45low, CD309+ and CD133+. A significant increase in EPC frequency in RA-ILD+ patients, as well as in RA-ILD? and IPF patients, was found when compared with controls (p < 0.001, p = 0.02 and p < 0.001, respectively). RA-ILD+ patients exhibited a higher EPC frequency than the RA-ILD? ones (p = 0.003), but lower than IPF patients (p < 0.001). Our results suggest that EPC increase may represent a reparative compensatory mechanism in patients with RA-ILD+. The degree of EPC frequency may help to identify the presence of ILD in RA patients and to discriminate RA-ILD+ from IPFThis work was partially supported by the European Regional Development Fund (ERDF) and ‘Fondo de Investigación Sanitaria’ [PI18/00043] from Instituto de Salud Carlos III (ISCIII), Health Ministry, Spain. VP-C is supported by a pre-doctoral grant from IDIVAL [PREVAL 18/01]. SR-M is supported by funds of RETICS Program [RD16/0012/0009, ISCIII, co-funded by ERDF]. BA-M is a recipient of a ‘López Albo’ Post-Residency Programme funded by Servicio Cántabro de Salud. LL-G is supported by funds of ISCIII, co-funded by ERDF [PI18/00042]. OG is beneficiary of a grant funded by Xunta de Galicia, Consellería de Educación, Universidade Formación Profesional and Consellería de Economía, Emprego e Industria (GAIN), GPC IN607B2019/10. RL-M is a recipient of a Miguel Servet type I fellowship [ISCIII, co-funded by European Social Fund—ESF, CP16/00033]