Luminescent properties of Bi-doped polycrystalline KAlCl4

We observed an intensive near-infrared luminescence in Bi-doped KAlCl4 polycrystalline material. Luminescence dependence on the excitation wavelength and temperature of the sample was studied. Our experimental results allow asserting that the luminescence peaked near 1 um belongs solely to Bi+ ion which isomorphically substitutes potassium in the crystal. It was also demonstrated that Bi+ luminescence features strongly depend on the local ion surroundings

Enfermedad de Gaucher en Argentina: un informe del Registro Internacional de Gaucher y del Grupo Argentino de Diagnóstico y Tratamiento de la Enfermedad de Gaucher

La Enfermedad de Gaucher por su baja frecuencia está incluida dentro de las enfermedades huérfanas. En 1991 comenzó el ingreso de pacientes en el Registro Internacional de Gaucher. En 1992 se incorporaron los primeros dos pacientes de Latinoamérica. En 2006 se creó el Grupo Argentino de Diagnóstico y Tratamiento de la Enfermedad de Gaucher siendo sus objetivos principales el entendimiento de la prevalencia, presentación, manejo y tratamiento de la Enfermedad de Gaucher en Argentina. Hasta el 1 de febrero del 2013 ingresaron al Registro Internacional 5.986 pacientes provenientes de 60 países, de los cuales 133 (2.22%) fueron argentinos. El análisis de esta publicación fue realizado sobre 133 pacientes con Enfermedad de Gaucher. Esta es la primera publicación del Grupo Argentino de Diagnóstico y Tratamiento en base a los datos del Registro Internacional. La casuística argentina mostró un predominio femenino y la forma clínica más frecuente fue el tipo 1 (97.7%, n=128). El genotipo fue identificado en 57 pacientes (42.9%), siendo el más frecuente el N370S/ otro alelo (82.5%). Entre los pacientes con datos reportados, los síntomas basales predominantes, previos al inicio del tratamiento con Imiglucerasa que predominaron fueron la esplenomegalia (100%, n=13) y la hepatomegalia (88.9%, n=8) y como citopenias más frecuentes, la trombocitopenia (64.2%, n=34) y la anemia (45.9%, n=28). La infiltración de la médula ósea como un marcador específico de enfermedad ósea se encontró en el 50% de los pacientes. En total, el 85.7% de los pacientes argentinos reciben terapia de reemplazo enzimático con Imiglucerasa, lográndose las metas terapéuticas, en la mayoría de los casos, en la última evaluación. Las metas terapéuticas más frecuentemente alcanzadas resultaron: el control de las manifestaciones óseas (dolor óseo y crisis ósea, 81.9% y 99% respectivamente) y la normalización de la hemoglobina (86.5%). La terapia de reemplazo enzimática con Imiglucerasa, a largo plazo en la población argentina demostró ser una herramienta eficaz para mejorar los parámetros clínicos y bioquímicos de la Enfermedad de Gaucher tipo1.Fil: Drelichman, G.. Gobierno de la Ciudad de Buenos Aires. Hospital General de Niños "Ricardo Gutiérrez"; ArgentinaFil: Fernández Escobar, Nicolás. Gobierno de la Ciudad de Buenos Aires. Hospital General de Niños "Ricardo Gutiérrez"; ArgentinaFil: Basack, Nora. Gobierno de la Ciudad de Buenos Aires. Hospital General de Niños "Ricardo Gutiérrez"; ArgentinaFil: Kohan, R.. Registro Argentino de Gaucher; ArgentinaFil: Watman, N.. Gobierno de la Ciudad de Buenos Aires. Hospital General de Agudos "Ramos Mejía"; ArgentinaFil: Bolesina, M.. Gobierno de la Ciudad de Buenos Aires. Hospital General de Agudos "Ramos Mejía"; ArgentinaFil: Elena, G.. Gobierno de la Ciudad de Buenos Aires. Hospital General de Niños Pedro Elizalde (ex Casa Cuna); ArgentinaFil: Veber, S. E.. Gobierno de la Ciudad de Buenos Aires. Hospital General de Niños Pedro Elizalde (ex Casa Cuna); ArgentinaFil: Dragosky, M.. Gobierno de la Ciudad de Buenos Aires. Hospital de Oncología Marie Curie; ArgentinaFil: Annetta, I.. Gobierno de la Ciudad de Buenos Aires. Hospital de Oncología Marie Curie; ArgentinaFil: Feliu, A.. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; ArgentinaFil: Sciuccati, Gabriela. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; ArgentinaFil: Cuello, María Fernanda. Provincia de Buenos Aires. Ministerio de Salud. Hospital de Niños "Sor María Ludovica" de la Plata; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Fynn, Alcira. Provincia de Buenos Aires. Ministerio de Salud. Hospital de Niños "Sor María Ludovica" de la Plata; ArgentinaFil: Dodelson de Kremer, Raquel. Provincia de Buenos Aires. Ministerio de Salud. Hospital de Niños "Sor María Ludovica" de la Plata; ArgentinaFil: Angaroni, Celia Juana. Provincia de Buenos Aires. Ministerio de Salud. Hospital de Niños "Sor María Ludovica" de la Plata; ArgentinaFil: Giner Ayala, Alicia. Provincia de Buenos Aires. Ministerio de Salud. Hospital de Niños "Sor María Ludovica" de la Plata; ArgentinaFil: Del Valle Oller, Ana María. Provincia de Buenos Aires. Ministerio de Salud. Hospital de Niños "Sor María Ludovica" de la Plata; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Guelbert, Norberto Bernardo. Provincia de Buenos Aires. Ministerio de Salud. Hospital de Niños "Sor María Ludovica" de la Plata; ArgentinaFil: Delgado, María Andrea. Provincia de Buenos Aires. Ministerio de Salud. Hospital de Niños "Sor María Ludovica" de la Plata; ArgentinaFil: Becerra, Adriana Berónica. Provincia de Buenos Aires. Ministerio de Salud. Hospital de Niños "Sor María Ludovica" de la Plata; ArgentinaFil: Oliveri, María Beatriz. Universidad de Buenos Aires. Facultad de Medicina. Hospital de Clínicas General San Martín; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Larroudé, M.. Centro Médico TIEMPO; ArgentinaFil: Masllorens, F.. Provincia de Buenos Aires. Ministerio de Salud. Hospital Nacional “Prof. Dr. A. Posadas"; ArgentinaFil: Szlago, M.. Fundación para el eEstudio de las Enfermedades Neurometabólicas; Argentina. Laboratorio de Neuroquímica “Dr. N. A. Chamoles”; ArgentinaFil: Schenone, A.. Laboratorio de Neuroquímica “Dr. N. A. Chamoles”; Argentina. Fundación para el eEstudio de las Enfermedades Neurometabólicas; Argentin

Automated Potentiometric Titrations in KCl/Water-Saturated Octanol: Method for Quantifying Factors Influencing Ion-Pair Partitioning

The knowledge base of factors influencing ion pair partitioning is very sparse, primarily because of the difficulty in determining accurate log PI values of desirable low molecular weight (MW) reference compounds. We have developed a potentiometric titration procedure in KCl/water-saturated octanol that provides a link to log PI through the thermodynamic cycle of ionization and partitioning. These titrations have the advantage of being independent of the magnitude of log P, while maintaining a reproducibility of a few hundredths of a log P in the calculated difference between log P neutral and log P ion pair (diff (log PN − I)). Simple model compounds can be used. The titration procedure is described in detail, along with a program for calculating pKa′′ values incorporating the ionization of water in octanol. Hydrogen bonding and steric factors have a greater influence on ion pairs than they do on neutral species, yet these factors are missing from current programs used to calculate log PI and log D. In contrast to the common assumption that diff (log PN − I) is the same for all amines, they can actually vary more than 3 log units, as in our examples. A major factor affecting log PI is the ability of water and the counterion to approach the charge center. Bulky substituents near the charge center have a negative influence on log PI. On the other hand, hydrogen bonding groups near the charge center have the opposite effect by lowering the free energy of the ion pair. The use of this titration method to determine substituent ion pair stabilization values (IPS) should bring about more accurate log D calculations and encourage species-specific QSAR involving log DN and log DI. This work also brings attention to the fascinating world of nature’s highly stabilized ion pairs

Drug Absorption Modeling as a Tool to Define the Strategy in Clinical Formulation Development

The purpose of this mini review is to discuss the use of physiologically-based drug absorption modeling to guide the formulation development. Following an introduction to drug absorption modeling, this article focuses on the preclinical formulation development. Case studies are presented, where the emphasis is not only the prediction of absolute exposure values, but also their change with altered input values. Sensitivity analysis of technologically relevant parameters, like the drug’s particle size, dose and solubility, is presented as the basis to define the clinical formulation strategy. Taking the concept even one step further, the article shows how the entire design space for drug absorption can be constructed. This most accurate prediction level is mainly foreseen once clinical data is available and an example is provided using mefenamic acid as a model drug. Physiologically-based modeling is expected to be more often used by formulators in the future. It has the potential to become an indispensable tool to guide the formulation development of challenging drugs, which will help minimize both risks and costs of formulation development

Deciphering Diseases and Biological Targets for Environmental Chemicals using Toxicogenomics Networks

Exposure to environmental chemicals and drugs may have a negative effect on human health. A better understanding of the molecular mechanism of such compounds is needed to determine the risk. We present a high confidence human protein-protein association network built upon the integration of chemical toxicology and systems biology. This computational systems chemical biology model reveals uncharacterized connections between compounds and diseases, thus predicting which compounds may be risk factors for human health. Additionally, the network can be used to identify unexpected potential associations between chemicals and proteins. Examples are shown for chemicals associated with breast cancer, lung cancer and necrosis, and potential protein targets for di-ethylhexyl-phthalate, 2,3,7,8-tetrachlorodibenzo-p-dioxin, pirinixic acid and permethrine. The chemical-protein associations are supported through recent published studies, which illustrate the power of our approach that integrates toxicogenomics data with other data types

A physicochemical descriptor-based scoring scheme for effective and rapid filtering of kinase-like chemical space

<p>Abstract</p> <p>Background</p> <p>The current chemical space of known small molecules is estimated to exceed 10⁶⁰structures. Though the largest physical compound repositories contain only a few tens of millions of unique compounds, virtual screening of databases of this size is still difficult. In recent years, the application of physicochemical descriptor-based profiling, such as Lipinski's rule-of-five for drug-likeness and Oprea's criteria of lead-likeness, as early stage filters in drug discovery has gained widespread acceptance. In the current study, we outline a kinase-likeness scoring function based on known kinase inhibitors.</p> <p>Results</p> <p>The method employs a collection of 22,615 known kinase inhibitors from the ChEMBL database. A kinase-likeness score is computed using statistical analysis of nine key physicochemical descriptors for these inhibitors. Based on this score, the kinase-likeness of four publicly and commercially available databases, i.e., National Cancer Institute database (NCI), the Natural Products database (NPD), the National Institute of Health's Molecular Libraries Small Molecule Repository (MLSMR), and the World Drug Index (WDI) database, is analyzed. Three of these databases, i.e., NCI, NPD, and MLSMR are frequently used in the virtual screening of kinase inhibitors, while the fourth WDI database is for comparison since it covers a wide range of known chemical space. Based on the kinase-likeness score, a kinase-focused library is also developed and tested against three different kinase targets selected from three different branches of the human kinome tree.</p> <p>Conclusions</p> <p>Our proposed methodology is one of the first that explores how the narrow chemical space of kinase inhibitors and its relevant physicochemical information can be utilized to build kinase-focused libraries and prioritize pre-existing compound databases for screening. We have shown that focused libraries generated by filtering compounds using the kinase-likeness score have, on average, better docking scores than an equivalent number of randomly selected compounds. Beyond library design, our findings also impact the broader efforts to identify kinase inhibitors by screening pre-existing compound libraries. Currently, the NCI library is the most commonly used database for screening kinase inhibitors. Our research suggests that other libraries, such as MLSMR, are more kinase-like and should be given priority in kinase screenings.</p