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1.
Clin Lymphoma Myeloma Leuk ; 21(4): 267-278.e10, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33303421

RESUMEN

INTRODUCTION: The prognostic value of B-cell lymphoma 2 (BCL2) expression in de novo diffuse large B-cell lymphoma (DLBCL) treated with immunochemotherapy is of interest to define a target patient population for clinical development of BCL2 inhibitors. We aimed to develop a reproducible immunohistochemistry algorithm and assay to determine BCL2 protein expression and assess the prognostic value of BCL2 in newly diagnosed DLBCL cohorts. PATIENTS AND METHODS: The prospectively defined algorithm incorporated BCL2 staining intensity and percentage of BCL2-positive cells. Functionally relevant cutoffs were based on the sensitivity of lymphoma cell lines to venetoclax. This assay was highly reproducible across laboratories. The prognostic impact of BCL2 expression was assessed in DLBCL patients from the phase 3 MAIN (n = 230) and GOYA (n = 366) trials, and a population-based registry (n = 310). RESULTS: Approximately 50% of tumors were BCL2 positive, with a higher frequency in high International Prognostic Index (IPI) and activated B-cell-like DLBCL subgroups. BCL2 expression was associated with poorer progression-free survival in the MAIN study (hazard ratio [HR], 1.66; 95% confidence interval [CI], 0.81-3.40; multivariate Cox regression adjusted for IPI and cell of origin). This trend was confirmed in the GOYA and registry cohorts in adjusted multivariate analyses (GOYA: HR, 1.72; 95% CI, 1.05-2.82; registry: HR, 1.89; 95% CI, 1.29-2.78). Patients with BCL2 immunohistochemistry-positive and IPI-high disease had the poorest prognosis: 3-year progression-free survival rates were 51% (GOYA) and 37% (registry). CONCLUSION: Findings support use of our BCL2 immunohistochemistry scoring system and assay to select patients with BCL2-positive tumors for future studies.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Biomarcadores de Tumor/genética , Linfoma de Células B Grandes Difuso/mortalidad , Proteínas Proto-Oncogénicas c-bcl-2/genética , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Biomarcadores de Tumor/análisis , Ensayos Clínicos Fase III como Asunto , Estudios de Cohortes , Resistencia a Antineoplásicos/genética , Femenino , Humanos , Estimación de Kaplan-Meier , Linfoma de Células B Grandes Difuso/tratamiento farmacológico , Linfoma de Células B Grandes Difuso/genética , Linfoma de Células B Grandes Difuso/patología , Masculino , Persona de Mediana Edad , Estudios Multicéntricos como Asunto , Pronóstico , Supervivencia sin Progresión , Proteínas Proto-Oncogénicas c-bcl-2/análisis , Ensayos Clínicos Controlados Aleatorios como Asunto , Sistema de Registros/estadística & datos numéricos , Adulto Joven
2.
Inorg Chem ; 56(21): 13535-13546, 2017 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-29048915

RESUMEN

Understanding the origin of cooperativity and the equilibrium temperature of transition (T1/2) displayed by the spin-crossover (SCO) compounds as well as controlling these parameters are of paramount importance for future applications. For this task, the occurrence of polymorphism, presented by a number of SCO complexes, may provide deep insight into the influence of the supramolecular organization on the SCO behavior. In this context, herein we present a novel family of mononuclear octahedral FeII complexes with formula cis-[Fe(bqen)(NCX)2], where bqen is the chelating tetradentate ligand N,N'-bis(8-quinolyl)ethane-1,2-diamine and X = S, Se. Depending on the preparation method, these compounds crystallize in either the orthorhombic or the trigonal symmetry systems. While the orthorhombic phase is composed of a racemic mixture of mononuclear complexes (polymorph I), the trigonal phase contains only one of the two possible enantiomers (Λ or Δ), thereby generating a chiral crystal (polymorph II). The four derivatives undergo SCO behavior with well-differentiated T1/2 values occurring in the interval 90-233 K. On one hand, T1/2 is about 110 K (polymorph I) and 87 K (polymorph II) higher for the selenocyanate derivatives in comparison to those for their thiocyanate counterparts. These differences in T1/2 are ascribed not only to the higher ligand field induced by the selenocyanate anion but also to a remarkable difference in the structural reorganization of the [FeN6] coordination core upon SCO. Likewise, the higher cooperativity observed for the thiocyanate derivatives seems to be related to their stronger intermolecular interactions within the crystal. On the other hand, T1/2 is about 53 K (thiocyanate) and 29 K (selenocyanate) higher for the trigonal polymorph II in comparison to those for the orthorhombic polymorph I. These differences, and the small changes observed in cooperativity, stem from the slightly different hetero- and homochiral crystal packing generated by the cis-[Fe(bqen)(NCX)2] molecules, which determines subtle adaptations in the intermolecular contacts and the FeII coordination core.

3.
Org Biomol Chem ; 8(13): 2986-92, 2010 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-20461267

RESUMEN

Functionalized fluorescent glycans have the potential to act as tools to detect and analyze protein-carbohydrate interactions. We present here a facile strategy for immobilization of functionalized lactose as a model disaccharide. Bioactivity was tested with three members of the adhesion/growth-regulatory galectins family in different types of assay, i.e. matrix in surface plasmon resonance (SPR), free ligand in solution by STD/trNOESY and docking measurements. In all cases, the activity of the disaccharide was maintained. The attachment of this new fluorescent glycoconjugate to the surface results in a well-defined interface, enabling desired orientational flexibility and enhanced access of binding partners. The results indicate that this new glycoconjugate exhibits binding affinity to galectin-1, 3 and CG-16. Kinetic analysis of the interaction between these galectins and immobilized glycoconjugate by SPR yielded a K(D) of 1.01 mM for galectin-1, 83.5 microM for galectin-3 and 0.28 mM for CG-16. No major contacts to the aglyconic part were detected, which might compromise the specificity of the binding process with other headgroups. Thus, testing these proteins offers the potential for medical applications to detect these endogenous effectors or further derivatives and characterize their carbohydrate specificity.


Asunto(s)
Galectinas/metabolismo , Glicoconjugados/metabolismo , Resonancia Magnética Nuclear Biomolecular , Resonancia por Plasmón de Superficie , Animales , Bovinos , Colorantes Fluorescentes/metabolismo , Galectinas/química , Glicoconjugados/química , Humanos , Ratones , Modelos Moleculares , Unión Proteica , Estructura Terciaria de Proteína , Espectrometría de Fluorescencia
4.
Bioconjug Chem ; 20(4): 673-82, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19267474

RESUMEN

Suitable glycan derivatives will find immediate application in the study of their interactions. Here, we present an efficient synthetic strategy to introduce a fluorescent tag functionalized with an amino group into a model disaccharide structure (lactose). This strategy led to the maintenance of bioactivity, checked by the study of the interaction of this bioconjugate with a plant lectin (mistletoe lectin 1) by NMR spectroscopy, computational docking, and surface plasmon resonance (SPR). To demonstrate the versatility of this approach, we immobilized the new glycan derivatives on different surfaces, and a comparative analysis is presented and can be successfully used for biomimetic carbohydrate-protein interaction studies on the SPR biochip.


Asunto(s)
Colorantes Fluorescentes/química , Polisacáridos/química , Resonancia por Plasmón de Superficie/métodos , 2-Naftilamina/análogos & derivados , 2-Naftilamina/química , Colorantes Fluorescentes/síntesis química , Colorantes Fluorescentes/metabolismo , Lactosa/química , Ligandos , Conformación Molecular , Lectinas de Plantas/metabolismo , Polisacáridos/síntesis química , Polisacáridos/metabolismo , Proteínas Inactivadoras de Ribosomas/metabolismo , Proteínas Inactivadoras de Ribosomas Tipo 2 , Espectrometría de Fluorescencia , Espectrofotometría Ultravioleta , Especificidad por Sustrato , Propiedades de Superficie , Toxinas Biológicas/metabolismo
5.
Biosens Bioelectron ; 24(6): 1788-91, 2009 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-18823769

RESUMEN

A novel and rapid approach to quantify chloride concentration in sweat for early detection of cystic fibrosis (CF) is shown in this work. Disposable screen-printed sensor (SPS) devices capable to induce sweat and measure the chloride concentration are presented. Pilocarpine, which was forced into de skin by means of iontophoresis, has been used to stimulate the sweat glands. Chloride concentration has been directly measured on the skin by potentiometry. The performance of the devices has been tested in synthetic samples, obtaining good agreement with the Nernst equation. Sensors reproducibility has been analyzed in terms of residual standard deviation (RSD), obtaining a value of 8% (n=6 and alpha=0.05). Finally, the application of these sensors in several volunteers has been carried out. The results were compared with the method generally used in hospitals, obtaining deviations minor than 8%.


Asunto(s)
Técnicas Biosensibles/instrumentación , Cloruros/análisis , Fibrosis Quística/diagnóstico , Fibrosis Quística/metabolismo , Equipos Desechables , Electroquímica/instrumentación , Sudor/química , Adulto , Biomarcadores/análisis , Diseño de Equipo , Análisis de Falla de Equipo , Femenino , Humanos , Masculino , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Adulto Joven
6.
Biophys J ; 95(3): 1336-48, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18456829

RESUMEN

The bacterial PEP:sugar PTS consists of a cascade of several proteins involved in the uptake and phosphorylation of carbohydrates, and in signal transduction pathways. Its uniqueness in bacteria makes the PTS a target for new antibacterial drugs. These drugs can be obtained from peptides or protein fragments able to interfere with the first reaction of the protein cascade: the phosphorylation of the HPr by the first enzyme, the so-called enzyme EI. To that end, we designed a peptide, HPr(9-30), spanning residues 9 to 30 of the intact HPr protein, containing the active site histidine (His-15) and the first alpha-helix of HPr of Streptomyces coelicolor, HPr(sc). By using fluorescence and circular dichroism, we first determined qualitatively that HPr(sc) and HPr(9-30) did bind to EI(sc), the enzyme EI from S. coelicolor. Then, we determined quantitatively the binding affinities of HPr(9-30) and HPr(sc) for EI(sc) by using ITC and STD-NMR. The STD-NMR experiments indicate that the epitope region of HPr(9-30) was formed by residues Leu-14, His-15, Ile-21, and Val-23. The binding reaction between EI(sc) and HPr(sc) is enthalpy driven and in other species is entropy driven; further, the affinity of HPr(sc) for EI(sc) was smaller than in other species. However, the affinity of HPr(9-30) for EI(sc) was only moderately lower than that of EI(sc) for HPr(sc), suggesting that this peptide could be considered a promising hit compound for designing new inhibitors against the PTS.


Asunto(s)
Mapeo Epitopo/métodos , Epítopos/química , Péptidos/química , Sistema de Fosfotransferasa de Azúcar del Fosfoenolpiruvato/química , Fosfotransferasas (Aceptor del Grupo Nitrogenado)/química , Streptomyces coelicolor/enzimología , Sitios de Unión , Unión Proteica
7.
Glycoconj J ; 25(7): 633-46, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18347977

RESUMEN

The emerging role of glycans as versatile biochemical signals in diverse aspects of cellular sociology calls for establishment of sensitive methods to monitor carbohydrate recognition by receptors such as lectins. Most of these techniques involve the immobilization of one of the binding partners on a surface, e.g. atomic force microscopy, glycan array and Surface Plasmon Resonance (SPR), hereby simulating cell surface presentation. Here, we report the synthesis of fluorescent glycoconjugates, with a functionalization strategy which avoids the frequently occurring ring opening at the reducing end for further immobilization on a surface or derivatization with biotin. In order to improve the versatility of these derivatized glycans for biological studies, a new approach for the synthesis of biotinylated and fluorescent glycans has also been realized. Finally, to illustrate their usefulness the neoglycoconjugates were immobilized on different surfaces, and the interaction analysis with a model lectin, the toxin from mistletoe, proved them to act as potent ligands, underscoring the merit of the presented synthetic approach.


Asunto(s)
Biotina/química , Lectinas de Plantas/metabolismo , Polisacáridos/síntesis química , Análisis por Matrices de Proteínas , Resonancia por Plasmón de Superficie/métodos , Aminación , Biotinilación , Conformación de Carbohidratos , Colorantes Fluorescentes , Glicoconjugados/síntesis química , Glicoconjugados/química , Cinética , Espectroscopía de Resonancia Magnética , Muérdago/química , Modelos Moleculares , Lectinas de Plantas/química , Polisacáridos/química
8.
Lung Cancer ; 59(2): 246-54, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17889402

RESUMEN

Lung cancer survival varies greatly from one European country to another. Differences in data collection may account for some of the variations observed. The aim of this work was to ascertain the survival rate in diverse Spanish regions and to analyse the influence of age and other prognostic factors. This was a prospective, observational, multiregional study carried out in 10 hospitals from 8 different Spanish regions. Epidemiological and clinical data, diagnostic and therapeutic procedures, and 3-year survival were recorded according to a common protocol and uniform criteria in 1027 patients with lung cancer diagnosed in 2003. Thirteen (1.26%) were lost to follow-up. The average 3-year survival rate in the remaining 1014 patients was 13.8% with regional rates varying from 6.7% to 19.7%. The resection rate also varied greatly. Early TNM stage, surgical treatment, and asymptomatic status at diagnosis were good independent prognostic factors. Cardiovascular comorbidity and weight loss had an adverse influence on survival. Patients over the age of 70 years were more often asymptomatic at diagnosis; they had less advanced disease and more comorbidity, received less active treatment and had worse survival. The average long-term survival rate in this Spanish series was similar to that reported for other European countries. It varied widely between regions depending on the resection rate. We conclude that although older patients are diagnosed at less advanced stages of disease, they have worse survival because they are less likely to receive effective therapy.


Asunto(s)
Neoplasias Pulmonares/mortalidad , Factores de Edad , Anciano , Terapia Combinada , Femenino , Estudios de Seguimiento , Humanos , Neoplasias Pulmonares/terapia , Masculino , Pronóstico , Estudios Prospectivos , Distribución por Sexo , España/epidemiología , Tasa de Supervivencia/tendencias
9.
Nano Lett ; 7(6): 1603-8, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17489639

RESUMEN

Multiwalled carbon nanotubes grown on gold electrodes manufactured by microtechnology techniques have been used as a platform for oriented and stable immobilization of a Ni-Fe hydrogenase. Microscopic and electrochemical characterization of the system are presented. High-density currents due to H2 oxidation electrocatalysis, stable for over a month under continuous operational conditions, were measured. The functional properties of this nanostructured hydrogenase electrode are suitable for hydrogen biosensing and biofuel applications.


Asunto(s)
Cristalización/métodos , Electroquímica/métodos , Hidrógeno/química , Hidrogenasas/química , Microelectrodos , Nanotecnología/métodos , Nanotubos de Carbono/química , Adsorción , Electroquímica/instrumentación , Hidrogenasas/ultraestructura , Sustancias Macromoleculares/química , Ensayo de Materiales , Conformación Molecular , Nanotecnología/instrumentación , Nanotubos de Carbono/ultraestructura , Oxidación-Reducción , Tamaño de la Partícula , Unión Proteica , Propiedades de Superficie
10.
Salud pública Méx ; 37(supl): 77-87, 1995. ilus
Artículo en Español | LILACS | ID: lil-167491

RESUMEN

Las Organizaciones Inteligentes (OI) son un instrumento de gran ayuda para organizar y conducir acciones de vigilancia, prevención y control. Son tecnología de punta en la administración; permiten generar esquemas del comportamiento de estructuras y políticas de organizaciones, describen sistématicamente problemas e integran modelos computalizados. Con esto se desarrollan pensamientos sistématicos; producen una visión compartida; crean modelos mentales de aprendizaje y superación continuos; se aprende en equipo; y se mejora el dominio personal. El avance científico-tecnológico ha producido una información impresionante en medicina, concomitante crecimiento de sus organizaciones y dificultad en las respuestas debido a cambios e innovaciones repentinos y constantes por ello se justifican las OI. Este trabajo está orientado a probar la utilidad de la tecnología de OI en el ordenamiento y sistematización de la información sobre los acontecimientos de las ciencias médicas. Se seleccionó el dengue para ejemplificar la aplicación de dicha tecnología porque representa un problema de crecimiento, importancia en el continente y en México, es complejo, puede evolucionar a formas de mayor gravedad en la población y es factible de analizarse en forma sistémica


Intelligent organizations (IO) represent a valuable tool to organize and guide dengue fever surveillance, prevention and control interventions. IO entail state of the art technology in managerial science to generate behavioral frameworks of organizational structures and policies. They present a systematic description of problems and construct computerized models to develop systemic thinking; they produce a shared vision and build progressive mental learning and advancement models. Also, IO promote team building and personal control skills. Scientific-technological advances have produced a wealth of information in medicine, with the corresponding growth of organizations and difficulty of responses because of sudden and incessant change. This new environment calls for the application of IO know-how. This article is oriented to prove the usefulness of the IO technology in the ordering and systematization of the reports about the medical sciences facts. Dengue was chosen to exemplify the use of IO technology as it represents an increasing health problem in America, as well as in Mexico; it is so complex that it can evolve to a more serious problem, besides it can be analized within a systemic method.


Asunto(s)
Organización y Administración , Toma de Decisiones Asistida por Computador , Sistemas de Salud , Modelos Organizacionales , Dengue/prevención & control , México , Política Organizacional , Monitoreo Epidemiológico
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