Inhibition of proliferation of HT-29 colon adenocarcinorna cells by carboxylate NSAIDs and their acyl glucuronides

Many nonsteroidal anti-inflammatory drugs (NSAIDs) which have antiproliferative activity in colon cancer cells are carboxylate compounds forming acyl glucuronide metabolites. Acyl glucuronides are potentially reactive, able to hydrolyse, rearrange into isomers, and covalently modify proteins under physiological conditions. This study investigated whether the acyl glucuronides (and isomers) of the carboxylate NSAIDs diflunisal, zomepirac and diclofenac had antiproliferative activity on human adenocarcinoma. HT-29 cells in culture. Included as controls were the carboxylate NSAIDs themselves, the non-carboxylate NSAID piroxicam, and the carboxylate non-NSAID valproate, as well as its acyl glucuronide and isomers. The compounds were incubated at 1-3000 muM with HT-29 cells for 24 hr, with [H-3]-thymidine added for an additional 2 hr incubation. IC50 values were calculated from the concentration-inhibition response curves for thymidine uptake. The four NSAIDs inhibited thymidine uptake, with IC50 values about 200-500 muM. All of the NSAID acyl glucuronides (and isomers, tested in the case of diflunisal) showed antiproliferative activity broadly comparable to the parent drugs. This activity may stem from direct uptake of intact glucuronide/isomers followed by covalent modification of proteins critical in the cell replication process. However, hydrolysis during incubation and cellular uptake of liberated parent NSAID will play a role. In HT-29 cells incubated with zomepirac, covalently modified proteins in cytosol were detected by immunoblotting with a zomepirac antibody, suggesting that HT-29 cells do have the capacity to glucuronidate zomepirac. The anti-epileptic drug valproate had no effect on inhibition of thymidine uptake, though, surprisingly, its acyl glucuronide and isomers were active. The reasons for this are unclear at present. (C) 2001 Elsevier Science Inc. All rights reserved.

Activation of the peroxisome proliferator-activated receptor-alpha enhances cell death in cultured cerebellar granule cells

Peroxisome proliferator-activated receptor-alpha (PPAR alpha) is a member of the steroid hormone receptor superfamily. In rodents, PPAR alpha. alters genes involved in cell cycle regulation in hepatocytes. Some of these genes are implicated in neuronal cell death. Therefore, in this study, we examined the toxicological consequence of PPAR alpha activation in rat primary cultures of cerebellar granule neurons. Our studies demonstrated the presence of PPAR alpha mRNA in cultures by reverse transcriptase-polymerase chain reaction. After 10 days in vitro, cerebellar granule neuron cultures were incubated with the selective PPAR alpha activator 4-chloro-6-(2,3-xylidino)2-pyrimidinylthioacetic acid (Wy-14,643). The inherent toxicity of Wy-14,643 and the effect of PPAR alpha activation following toxic stimuli were assessed. In these studies, neurotoxicity was induced through reduction of extracellular [KCl] from 25 mM to 5.36 mM. We observed no inherent toxicity of Wy-1 4,643 (24 hr) in cultured cerebellar granule cells. However, after reduction of [KCl], cerebellar granule cell cultures incubated with Wy-14,643 showed significantly greater toxicity than controls. These results suggest a posssible role for PPAR(x in augmentation of cerebellar granule neuronal death after toxic stimuli. (C) 2001 Wiley-Liss, Inc.

The changing face of ciguatera

Ciguatera is a global disease caused by the consumption of certain warm-water fish (ciguateric fish) that have accumulated orally effective levels of sodium channel activator toxins (ciguatoxins) through the marine food chain. Symptoms of ciguatera include a range of gastrointestinal, neurological and cardiovascular disturbances. This review examines progress in our understanding of ciguatera from the work of Banner in the late 1950s to the present. Similarities and differences in ciguatera in the Pacific Ocean, Indian Ocean and Caribbean Sea are highlighted, and future research directions are suggested. (C) 2000 Elsevier Science Ltd. All rights reserved.

Inhibition of tubulin assembly and covalent binding to microtubular protein by valproic acid glucuronide in vitro

Acyl glucuronides are reactive metabolites of carboxylate drugs, able to undergo a number of reactions in vitro and in vivo, including isomerization via intramolecular rearrangement and covalent adduct formation with proteins. The intrinsic reactivity of a particular acyl glucuronide depends upon the chemical makeup of the drug moiety. The least reactive acyl glucuronide yet reported is valproic acid acyl glucuronide (VPA-G), which is the major metabolite of the antiepileptic agent valproic acid (VPA). In this study, we showed that both VPA-G and its rearrangement isomers (iso-VPA-G) interacted with bovine brain microtubular protein (MTP, comprised of 85% tubulin and 15% microtubule associated proteins {MAPs}). MTP was incubated with VPA, VPA-G and iso-VPA-G for 2 h at room temperature and pH 7.5 at various concentrations up to 4 mM. VPA-G and iso-VPA-G caused dose-dependent inhibition of assembly of MTP into microtubules, with 50% inhibition (IC50) values of 1.0 and 0.2 mM respectively, suggesting that iso-VPA-G has five times more inhibitory potential than VPA-G. VPA itself did not inhibit microtubule formation except at very high concentrations (greater than or equal to2 mM). Dialysis to remove unbound VPA-G and iso-VPA-G (prior to the assembly assay) diminished inhibition while not removing it. Comparison of covalent binding of VPA-G and iso-VPA-G (using [C-14]-labelled species) showed that adduct formation was much greater for iso-vTA-G. When [C-14]-iso-VPA-G was reacted with MTP in the presence of sodium cyanide (to stabilize glycation adducts), subsequent separation into tubulin and MAPs fractions by ion exchange chromatography revealed that 78 and 22% of the covalent binding occurred with the MAPs and tubulin fractions respectively. These experiments support the notion of both covalent and reversible binding playing parts in the inhibition of microtubule formation from MTP (though the acyl glucuronide of VPA is less important than its rearrangement isomers in this regard), and that both tubulin and (perhaps more importantly) MAPs form adducts with acyl glucuronides. (C) 2002 Elsevier Science Inc. All rights reserved.

Hepatic covalent adduct formation with zomepirac in the CD26-deficient mouse

Background and Aims: Zomepirac (ZP), a non-steroidal anti-inflammatory drug (NSAID), has been reported to cause immune-mediated liver injury. In vivo, ZP is metabolized to a chemically reactive acyl glucuronide conjugate (ZAG) which can undergo covalent adduct formation with proteins. Such acyl glucuronide-derived drug-protein adducts may be important in the development of immune and toxic responses caused by NSAID. We have shown using immunoabsorptions that the 110 kDa CD26 (dipeptidyl peptidase IV) is one of the hepatic target proteins for covalent modification by ZAG. In the present study, a CD26-deficient mouse strain was used to examine protein targets for covalent modification by ZP/metabolites in the liver. Methods and Results: The CD26-deficient phenotype was confirmed by immunohistochemistry, flow cytometry analysis, RT-PCR, enzyme assay and immunoblotting. Moreover, by using monoclonal antibody immunoblots, CD26 was not detected in the livers of ZP-treated CD26-deficient mice. Immunoblots using a polyclonal antiserum to ZP on liver from ZP-treated mice showed three major sizes of protein bands, in the 70, 110 and 140 kDa regions. Most, but not all, of the anti-ZP immunoreactivity in the 110 kDa region was absent from ZP-treated CD26-deficient mice. Conclusion: These data definitively showed that CD26 was a component of ZP-modified proteins in vivo. In addition, the data suggested that at least one other protein of approximately 110 kDa was modified by covalent adduct formation with ZAG. (C) 2002 Blackwell Science Asia Pty Ltd.

Effect of tamoxifen on the enzymatic activity of human cytochrome CYP2B6

Tamoxifen is primarily used in the treatment of breast cancer. It has been approved as a chemopreventive agent for individuals at high risk for this disease. Tamoxifen is metabolized to a number of different products by cytochrome P450 enzymes. The effect of tamoxifen on the enzymatic activity of bacterially expressed human cytochrome CYP2B6 in a reconstituted system has been investigated. The 7-ethoxy-4-(trifluoromethyl) coumarin O-deethylation activity of purified CYP2B6 was inactivated by tamoxifen in a time- and concentration-dependent manner. Enzymatic activity was lost only in samples that were incubated with both tamoxifen and NADPH. The inactivation was characterized by a K-l of 0.9 muM, a k(inact) of 0.02 min(-1), and a t(1/2) of 34 min. The loss in the 7-ethoxy-4-(trifluoromethyl) coumarin O-deethylation activity did not result in a similar percentage loss in the reduced carbon monoxide spectrum, suggesting that the heme moiety was not the major site of modification. The activity of CYP2B6 was not recovered after removal of free tamoxifen using spin column gel filtration. The loss in activity seemed to be due to a modification of the CYP2B6 and not reductase because adding fresh reductase back to the inactivated samples did not restore enzymatic activity. A reconstituted system containing purified CYP2B6, NADPH-reductase, and NADPH-generating system was found to catalyze tamoxifen metabolism to 4-OH-tamoxifen, 4'-OH-tamoxifen, and N-desmethyl-tamoxifen as analyzed by high-performance liquid chromatography analysis. Preliminary studies showed that tamoxifen had no effect on the activities of CYP1B1 and CYP3A4, whereas CYP2D6 and CYP2C9 exhibited a 25% loss in enzymatic activity.

Invertebrate D2 type dopamine receptor exhibits age-based plasticity of expression in the mushroom bodies of the honeybee brain

We have isolated a cDNA clone from the honeybee brain encoding a dopamine receptor, AmDop2, which is positively coupled to adenylyl cyclase. The transmembrane domains of this receptor are 88% identical to the orthologous Drosophila D2 dopamine receptor, DmDop2, though phylogenetic analysis and sequence homology both indicate that invertebrate and vertebrate D2 receptors are quite distinct. In situ hybridization to mRNA in whole-mount preparations of honeybee brains reveals gene expression in the mushroom bodies, a primary site of associative learning. Furthermore, two anatomically distinct cell types in the mushroom bodies exhibit differential regulation of AmDop2 expression. In all nonreproductive females (worker caste) and reproductive males (drones) the receptor gene is strongly and constitutively expressed in all mushroom body interneurons with small cell bodies. In contrast, the large cell-bodied interneurons exhibit dramatic plasticity of AmDop2 gene expression. In newly emerged worker bees (cell-cleaning specialists) and newly emerged drones, no AmDop2 transcript is observed in the large interneurons whereas this transcript is abundant in these cells in the oldest worker bees (resource foragers) and older drones. Differentiation of the mushroom body interneurons into two distinct classes (i.e., plastic or nonplastic with respect to AmDop2 gene expression) indicates that this receptor contributes to the differential regulation of distinct neural circuits. Moreover, the plasticity of expression observed in the large cells implicates this receptor in the behavioral maturation of the bee.

Estudio retrospectivo de pacientes con Gammapatía Monoclonal de Significado Incierto en el área de salud 6 de Valencia

L’objectiu del present estudi va ser estudiar a la població afecta de GMSI en l’àrea de salut 6 de València, així com la incidència de la mateixa. Es tracta d’un estudi descriptiu transversal retrospectiu observacional dels pacients amb aquesta patologia que van acudir al servei d’Hematologia de l’hospital de referència. Quant als resultats, encara que les dades analítiques i evolutives van ser similars a sèries anteriors (subtipus predominant IgG, 7.5% de progressió), el nombre de pacients i la incidència va ser menor de l'esperada, la qual cosa va restar pes estadístic a l'extrapolació dels resultats.

The expression level of BAALC-associated microRNA miR-3151 is an independent prognostic factor in younger patients with cytogenetic intermediate-risk acute myeloid leukemia.

Acute myeloid leukemia (AML) is a heterogeneous disease whose prognosis is mainly related to the biological risk conferred by cytogenetics and molecular profiling. In elderly patients (60 years) with normal karyotype AML miR-3151 have been identified as a prognostic factor. However, miR-3151 prognostic value has not been examined in younger AML patients. In the present work, we have studied miR-3151 alone and in combination with BAALC, its host gene, in a cohort of 181 younger intermediate-risk AML (IR-AML) patients. Patients with higher expression of miR-3151 had shorter overall survival (P=0.0025), shorter leukemia-free survival (P=0.026) and higher cumulative incidence of relapse (P=0.082). Moreover, in the multivariate analysis miR-3151 emerged as independent prognostic marker in both the overall series and within the unfavorable molecular prognostic category. Interestingly, the combined determination of both miR-3151 and BAALC improved this prognostic stratification, with patients with low levels of both parameters showing a better outcome compared with those patients harboring increased levels of one or both markers (P=0.003). In addition, we studied the microRNA expression profile associated with miR-3151 identifying a six-microRNA signature. In conclusion, the analysis of miR-3151 and BAALC expression may well contribute to an improved prognostic stratification of younger patients with IR-AML.

Formación y aplicación de las terapias complementarias en los cuidados de enfermería al paciente oncológico

Objetivo general: Analizar la formación de las enfermeras y la aplicación de las terapias complementarias (TC) en los cuidados de enfermería al paciente oncológico. Ámbito de estudio: El estudio se realizó en el hospital Duran i Reynals de l"Hospitalet de Llobregat, en las unidades de: hematología clínica, terapia intensiva, tratamiento programado, hospital de día, oncología médica, cuidados paliativos, consultas externas, soporte de la atención continuada, servicio de oncología radioterápica y en el equipo de soporte hospitalario. Diseño: Estudio descriptivo transversal. Método: Aplicación de un cuestionario elaborado que consta de dos apartados, uno de datos demográficos y otro apartado con 8 preguntas especificas. Participantes: Enfermeras del área asistencial de todos los turnos que trabajen en las unidades mencionadas. Análisis de datos: Para el análisis de los datos se ha utilizado el paquete estadístico SPSS15.0 para Windows y se ha realizado un análisis descriptivo para todas las variables. Variables cualitativas: frecuencias y porcentajes. Variables cuantitativas: medidas de tendencia central y de dispersión. Resultados: El 58,8% de las enfermeras ha realizado algún tipo de formación en TC. Las intervenciones mente-cuerpo son las más efectuadas en cuanto a formación, seguidas de las terapias manuales y las terapias de base energética. La relajación-visualización es la terapia que más aplican las enfermeras oncológicas. Conclusiones: La formación de las enfermeras oncológicas en las TC es fundamental para poder informar y asesorar a sus pacientes y poder cuidarlos de una forma más holística. La falta de tiempo y de disposición del hospital al reconocimiento y valor de las TC son los principales factores de dificultad que se encuentran las enfermeras oncológicas.

Gestión de residuos sanitarios (y 2). Qué facilita y/o dificulta la correcta gestión

Para la protección de la salud pública y evitación de los riesgos laborales derivados de la gestión incorrecta de los residuos sanitarios (RS), es necesario identificar los elementos que facilitan o dificultan las actitudes de prevención frente a la gestión avanzada de los RS. Objetivo: Identificar la actitud de los profesionales de la salud frente a la gestión de los RS. Objetivos específicos: Definir los elementos que dificultan y/o facilitan la eliminación de los RS. Conocer la valoración global que hacen los profesionales de la gestión de los RS. Identificar propuestas para mejorar la gestión de los RS. Material y métodos: La muestra abarca a 108 profesionales sanitarios de 2 centros hospitalarios de Barcelona y 2 centros hospitalarios de L"Hospitalet de Llobregat. Las unidades asistenciales escogidas para el estudio son los servicios de enfermedades infecciosas, medicina interna, urgencias, obstetricia y ginecología, neumología, radiología, oncología, hematología, cuidados intensivos y laboratorio. Se trata de un estudio descriptivo, no probabilístico. Criterios de inclusión: profesionales del turno de mañana, tarde y 12 h con más de un año de experiencia profesional. Criterios de exclusión: profesionales del turno de noche y en período de prácticas. Como instrumento de medida se ha utilizado un cuestionario elaborado y administrado por el equipo investigador. Las variables de estudio son: actitud, valoración global y propuestas. Análisis de los datos: SPSS 12.0. Resultados: Como elementos facilitadores tenemos que el 19,2% considera la percepción de riesgo; el 14,6%, la disponibilidad de recursos; el 10,6%, la formación específica; el 10,6%, la obligación de cumplir la legislación vigente, y el 1,7%, otros. Como factores que dificultan una actitud preventiva en la gestión de RS tenemos: el 16,4%, el desconocimiento de la normativa; el 10,9%, la presión asistencial; el 7,4%, la falta de recursos, y el 4,6%, otros. En cuanto a la valoración global, la mitad de los encuestados están bastante de acuerdo en la gestión realizada en sus unidades asistenciales, y en las propuestas que plantean destaca, con el 54,9%, la necesidad de más formación específica. Conclusiones: La percepción de riesgo, la disponibilidad de recursos y la formación se consideran los factores que facilitan la gestión correcta; y el desconocimiento de la normativa es el elemento que dificulta la misma. La valoración que hacen de la gestión de los RS de los compañeros en sus unidades asistenciales es muy aceptable, y más de la mitad de los profesionales sugieren la formación como la mejor estrategia para la gestión avanzada de los RS.

Gestión de residuos sanitarios (y 2). Qué facilita y/o dificulta la correcta gestión

Para la protección de la salud pública y evitación de los riesgos laborales derivados de la gestión incorrecta de los residuos sanitarios (RS), es necesario identificar los elementos que facilitan o dificultan las actitudes de prevención frente a la gestión avanzada de los RS. Objetivo: Identificar la actitud de los profesionales de la salud frente a la gestión de los RS. Objetivos específicos: Definir los elementos que dificultan y/o facilitan la eliminación de los RS. Conocer la valoración global que hacen los profesionales de la gestión de los RS. Identificar propuestas para mejorar la gestión de los RS. Material y métodos: La muestra abarca a 108 profesionales sanitarios de 2 centros hospitalarios de Barcelona y 2 centros hospitalarios de L"Hospitalet de Llobregat. Las unidades asistenciales escogidas para el estudio son los servicios de enfermedades infecciosas, medicina interna, urgencias, obstetricia y ginecología, neumología, radiología, oncología, hematología, cuidados intensivos y laboratorio. Se trata de un estudio descriptivo, no probabilístico. Criterios de inclusión: profesionales del turno de mañana, tarde y 12 h con más de un año de experiencia profesional. Criterios de exclusión: profesionales del turno de noche y en período de prácticas. Como instrumento de medida se ha utilizado un cuestionario elaborado y administrado por el equipo investigador. Las variables de estudio son: actitud, valoración global y propuestas. Análisis de los datos: SPSS 12.0. Resultados: Como elementos facilitadores tenemos que el 19,2% considera la percepción de riesgo; el 14,6%, la disponibilidad de recursos; el 10,6%, la formación específica; el 10,6%, la obligación de cumplir la legislación vigente, y el 1,7%, otros. Como factores que dificultan una actitud preventiva en la gestión de RS tenemos: el 16,4%, el desconocimiento de la normativa; el 10,9%, la presión asistencial; el 7,4%, la falta de recursos, y el 4,6%, otros. En cuanto a la valoración global, la mitad de los encuestados están bastante de acuerdo en la gestión realizada en sus unidades asistenciales, y en las propuestas que plantean destaca, con el 54,9%, la necesidad de más formación específica. Conclusiones: La percepción de riesgo, la disponibilidad de recursos y la formación se consideran los factores que facilitan la gestión correcta; y el desconocimiento de la normativa es el elemento que dificulta la misma. La valoración que hacen de la gestión de los RS de los compañeros en sus unidades asistenciales es muy aceptable, y más de la mitad de los profesionales sugieren la formación como la mejor estrategia para la gestión avanzada de los RS.

Implementación de una técnica para el desarrollo de los cultivos celulares en muestras de células de cordón umbilical del Banco de cordón del Hospital Universitario.

Tesis (Especialidad en el Laboratorio de Hematología) UANL, 2010.

La importancia en la cuenta leucocitaria y del volumen de la muestra para la decisión de criopreservar células de cordón umbilical

Tesis (Especialista en el Laboratorio de Hematología) U.A.N.L., 2006.