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1.
Public Health ; 216: 30-32, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36773386

RESUMEN

OBJECTIVES: Although there is growing evidence that in utero exposure to power plants increases the risk of adverse birth outcomes, studies have focused on coal-fired plants and single US locations, limiting generalizability. We used birth certificate data from 50 states and DC to examine the associations between prenatal exposure to power plants and birth outcomes overall and by race/ethnicity. METHODS: We linked 2009-2018 county-level microdata natality files on 34,674,911 singleton births from 50 states and DC with 9-month county-level averages of power plant fuel consumption based on month/year of birth. We estimated linear regression models for birth weight and gestational age and probit models for the dichotomous outcomes of low birth weight, small for gestational age (SGA), and preterm birth. We subsequently examined interactions between plant fuel consumption and race/ethnicity. RESULTS: Overall, 69.1% of counties had any power plant fuel consumption. Although we found no overall effects of prenatal exposure to power plants on birth weight or SGA, a significant interaction (both P < 0.01) revealed that a 10% increase in fuel consumption was associated with infants born to White women having slightly lower birth weights (1.76 g; 95% confidence interval = -2.87, -0.65) and higher risk of being born SGA (0.0002; 95% confidence interval = 0.0002, 0.0002). CONCLUSION: Power plants have negative effects on infant health, which exist independent of locality.


Asunto(s)
Nacimiento Prematuro , Efectos Tardíos de la Exposición Prenatal , Embarazo , Lactante , Recién Nacido , Humanos , Estados Unidos , Femenino , Resultado del Embarazo , Peso al Nacer , Centrales Eléctricas
3.
Geriatr Orthop Surg Rehabil ; 10: 2151459319876859, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31579528

RESUMEN

INTRODUCTION: The Vancouver algorithm recommends revision arthroplasty (RA) for Vancouver type B2 (VTB2) fractures. However, open reduction and internal fixation (ORIF) using locking compression plates (LCP) may be a valid and less invasive alternative treatment. MATERIALS AND METHODS: Between January 2007 and March 2017, we retrospectively recruited all patients treated with either ORIF with LCP or RA for VTB2 fractures in our clinic. All of the following were reviewed: the length of hospital stay, the operating time, the need for blood transfusions during and/or after surgery, implant-related and patient-related complications, need for revision surgery, and the radiological outcome. Additionally, the functional outcome was investigated. RESULTS: Fifty-nine patients were recruited. Thirty-five (59.3%) patients underwent RA, while 24 (40.7%) patients received ORIF with LCP. The median surgical time was 137.50 minutes in the LCP group compared to 160.00 minutes in the RA group (P = .051). Three (12.5%) patients in the LCP group and 10 (28.6%) patients in the RA group experienced an implant-associated complication (P = .131). Patient-related complications occurred in 3 (12.5%) patients in the LCP group versus 6 (17.1%) patients in the RA group (P = .628). The mean preoperative Parker mobility score was 9 points in both groups and decreased in both groups to a mean of 5 points in the LCP and 7 points in the RA group. DISCUSSION: Open reduction and internal fixation with LCP seems to be a less invasive procedure for VTB2 fractures in comparison to RA. It is a bone-sparing procedure that can be advantageous for further revision operations. Moreover, some fractures can only be anatomically reduced by ORIF with LCP, whereas for proximal fractures with a radiologically unambiguously loosened stem RA might be advantageous. CONCLUSION: In line with previously published studies, our data suggest that ORIF using LCP is a valid treatment option for VTB2 fractures.

4.
Epidemiol Infect ; 146(16): 2122-2130, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30173679

RESUMEN

The objective was to compare the performance of the updated Charlson comorbidity index (uCCI) and classical CCI (cCCI) in predicting 30-day mortality in patients with Staphylococcus aureus bacteraemia (SAB). All cases of SAB in patients aged ⩾14 years identified at the Microbiology Unit were included prospectively and followed. Comorbidity was evaluated using the cCCI and uCCI. Relevant variables associated with SAB-related mortality, along with cCCI or uCCI scores, were entered into multivariate logistic regression models. Global model fit, model calibration and predictive validity of each model were evaluated and compared. In total, 257 episodes of SAB in 239 patients were included (mean age 74 years; 65% were male). The mean cCCI and uCCI scores were 3.6 (standard deviation, 2.4) and 2.9 (2.3), respectively; 161 (63%) cases had cCCI score ⩾3 and 89 (35%) cases had uCCI score ⩾4. Sixty-five (25%) patients died within 30 days. The cCCI score was not related to mortality in any model, but uCCI score ⩾4 was an independent factor of 30-day mortality (odds ratio, 1.98; 95% confidence interval, 1.05-3.74). The uCCI is a more up-to-date, refined and parsimonious prognostic mortality score than the cCCI; it may thus serve better than the latter in the identification of patients with SAB with worse prognoses.


Asunto(s)
Bacteriemia/diagnóstico , Bacteriemia/mortalidad , Técnicas de Apoyo para la Decisión , Infecciones Estafilocócicas/diagnóstico , Infecciones Estafilocócicas/mortalidad , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Comorbilidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Prospectivos , Adulto Joven
5.
Arch Clin Neuropsychol ; 32(5): 555-573, 2017 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-28334392

RESUMEN

OBJECTIVE: Individuals with spinal cord injury (SCI), traumatic brain injury (TBI), and stroke experience a variety of neurologically related deficits across multiple domains of function. The NIH Toolbox for the Assessment of Neurological and Behavioral Function (NIHTB) examines motor, sensation, cognition, and emotional functioning. The purpose of this paper is to establish the validity of the NIHTB in individuals with neurologic conditions. METHODS: Community-dwelling individuals with SCI (n = 209), TBI (n = 184), or stroke (n = 211) completed the NIHTB. Relative risks for impaired performance were examined relative to a matched control groups. RESULTS: The largest group differences were observed on the Motor domain and for the Fluid Cognition measures. All groups were at increased risk for motor impairment relative to normative standards and matched controls. Fluid cognitive abilities varied across groups such that individuals with stroke and TBI performed more poorly than individuals with SCI; increased relative risks for impaired fluid cognition were seen for individuals in the stroke and TBI groups, but not for those in the SCI group. All three neurologic groups performed normally on most measures in the Sensation Battery, although TBI participants evidenced increased risk for impaired odor identification and the stroke group showed more vision difficulties. On the Emotion Battery, participants in all three groups showed comparably poor psychological well-being, social satisfaction, and self-efficacy, whereas the TBI group also evidenced slightly increased negative affect. CONCLUSIONS: Data provide support for the validity of the NIHTB in individuals with neurologic conditions.


Asunto(s)
Síntomas Afectivos/diagnóstico , Lesiones Traumáticas del Encéfalo/diagnóstico , Disfunción Cognitiva/diagnóstico , Técnicas de Diagnóstico Neurológico/normas , Trastornos del Movimiento/diagnóstico , Pruebas Neuropsicológicas/normas , Escalas de Valoración Psiquiátrica/normas , Trastornos de la Sensación/diagnóstico , Conducta Social , Traumatismos de la Médula Espinal/diagnóstico , Accidente Cerebrovascular/diagnóstico , Adulto , Síntomas Afectivos/etiología , Anciano , Lesiones Traumáticas del Encéfalo/complicaciones , Disfunción Cognitiva/etiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Trastornos del Movimiento/etiología , National Institutes of Health (U.S.) , Reproducibilidad de los Resultados , Trastornos de la Sensación/etiología , Traumatismos de la Médula Espinal/complicaciones , Accidente Cerebrovascular/complicaciones , Estados Unidos , Adulto Joven
6.
Int J Phytoremediation ; 19(7): 597-604, 2017 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-27739900

RESUMEN

The test strains Bacteroidetes bacterium (Ba), Pseudomonas fluorescens (Pf) and Variovorax sp. (Va) were selected in advance for their in vitro capability for growth promotion of rapeseed in the presence of increased concentrations of Cd, Cu, Pb and Zn in the medium. In the pot experiment, the strains were used for single Ba, Pf, Va or combined Ba + Pf, Ba + Va, Pf + Va, and Ba + Pf + Va inoculation of B. napus growing in contaminated soil from alluvial deposits. The positive effect of bacterial strains on plant growth was observed in vitro, but was not confirmed in situ in the contaminated soil, where the tested strains inhibited biomass production, rather than stimulating it. However, single inoculation with Ba significantly increased the chlorophyll content and K+ concentration in the leaves. The inoculation of rapeseed with Ba and Va strains was indicated to be the most promising combination for phytoextraction of Cd and Zn from contaminated soil. Combined inoculation with Pf+Va and Pf + Ba+Va significantly decreased the concentration of heavy metals in the roots of rapeseed. We conclude that suitable combinations of PGPR can control the metal uptake of B. napus, selectively increasing either metal extraction or metal stabilization in the rhizosphere and offering promising applications in soil remediation.


Asunto(s)
Biodegradación Ambiental , Brassica napus , Cadmio/metabolismo , Micorrizas/fisiología , Zinc/metabolismo , Metales Pesados , Contaminantes del Suelo
8.
Neuropsychol Rehabil ; 27(5): 603-617, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27150506

RESUMEN

This study examined the relationships between the Executive Function Performance Test (EFPT), the NIH Toolbox Cognitive Function tests, and neuropsychological executive function measures in 182 persons with traumatic brain injury (TBI) and 46 controls to evaluate construct, discriminant, and predictive validity. Construct validity: There were moderate correlations between the EFPT and the NIH Toolbox Crystallized (r = -.479), Fluid Tests (r = -.420), and Total Composite Scores (r = -.496). Discriminant validity: Significant differences were found in the EFPT total and sequence scores across control, complicated mild/moderate, and severe TBI groups. We found differences in the organisation score between control and severe, and between mild and severe TBI groups. Both TBI groups had significantly lower scores in safety and judgement than controls. Compared to the controls, the severe TBI group demonstrated significantly lower performance on all instrumental activities of daily living (IADL) tasks. Compared to the mild TBI group, the controls performed better on the medication task, the severe TBI group performed worse in the cooking and telephone tasks. Predictive validity: The EFPT predicted the self-perception of independence measured by the TBI-QOL (beta = -0.49, p < .001) for the severe TBI group. Overall, these data support the validity of the EFPT for use in individuals with TBI.


Asunto(s)
Lesiones Traumáticas del Encéfalo/complicaciones , Trastornos del Conocimiento/etiología , Función Ejecutiva/fisiología , Pruebas Neuropsicológicas , Adulto , Trastornos del Conocimiento/diagnóstico , Estudios Transversales , Femenino , Humanos , Juicio/fisiología , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Autoimagen , Estadísticas no Paramétricas , Índices de Gravedad del Trauma
9.
Int J Behav Med ; 24(2): 260-271, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-27481106

RESUMEN

PURPOSE: The way individuals attend to pain is known to have a considerable impact on the experience and chronification of pain. One method to assess the habitual "attention to pain" is the Pain Vigilance and Awareness Questionnaire (PVAQ). With the present study, we aimed to test the psychometric properties of the German version of the PVAQ across pain-free samples and across patients with acute and chronic pain. METHOD: Two samples of pain-free individuals (student sample (N = 255)/non-student sample (N = 362)) and two clinical pain samples (acute pain patients (N = 105)/chronic pain patients (N = 36)) were included in this cross-sectional evaluation of the German PVAQ. Factor structure was assessed using exploratory and confirmatory factor analyses. Reliability was assessed using internal consistency (Cronbach's alpha). Construct validity was tested by assessing correlations between PVAQ and theoretically related constructs. RESULTS: Exploratory factor analysis (non-student sample) and confirmatory factor analysis (student sample, acute pain patient sample) suggested that a two-factor solution best fitted our data ("attention to pain," "attention to changes in pain"). Internal consistency ranged from acceptable to good in all four samples. As hypothesized, the PVAQ correlated significantly with theoretically related constructs in all four samples, suggesting good construct validity in pain-free individuals and in pain patients. CONCLUSION: The German PVAQ shows good psychometric properties across samples of pain-free individuals and patients suffering from pain that are comparable to PVAQ versions of other languages. Thus, the German PVAQ seems to be a measure of pain vigilance equally valid as found in other countries.


Asunto(s)
Dolor Agudo/psicología , Dolor Crónico/psicología , Encuestas y Cuestionarios , Adolescente , Adulto , Concienciación , Estudios Transversales , Análisis Factorial , Femenino , Humanos , Lenguaje , Masculino , Persona de Mediana Edad , Dimensión del Dolor/métodos , Psicometría/métodos , Reproducibilidad de los Resultados , Adulto Joven
10.
Gene Ther ; 22(11): 883-92, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26125609

RESUMEN

Successful application of gene therapy strategies may require stringently regulated transgene expression. Along this line, we describe a doxycycline (Dox)-inducible 'all-in-one' lentiviral vector design using the pTET-T11 (TII) minimal-promoter and a reverse transactivator protein (rtTA2S-M2) driven by the phosphoglycerate kinase promoter allowing for tight regulation of transgene expression (Lv.TII vectors). Vector design was evaluated in human hematopoietic cells in the context of cytidine deaminase (hCDD)-based myeloprotective gene therapy. Upon Dox administration, a rapid (16-24 h) and dose-dependent (>0.04 µg ml(-1) Dox) onset of transgene expression was detected in Lv.TII.CDD gene-modified K562 cells as well as in primary human CD34(+) hematopoietic cells. Importantly, in both cell models low background transgene expression was observed in the absence of Dox. Functionality of Dox-inducible hCDD expression was demonstrated by >10-fold increase in cytosine arabinoside (1-ß-d-arabinofuranosylcytosine, Ara-C) resistance of Lv.TII.CDD-transduced K562 cells. In addition, Lv.TII.CDD-transduced CD34(+)-derived myeloid cells were protected from up to 300 nm Ara-C (control affected from 50 nm onwards). These data clearly demonstrate the suitability of our self-inactivating lentiviral vector to induce robust, tightly regulated transgene expression in human hematopoietic cells with minimal background activity and highlight the potential of our construct in myeloprotective gene therapy strategies.


Asunto(s)
Terapia Genética/métodos , Células Madre Hematopoyéticas/efectos de los fármacos , Células Madre Hematopoyéticas/fisiología , Lentivirus/genética , Antimetabolitos Antineoplásicos/toxicidad , Citarabina/toxicidad , Citidina Desaminasa/biosíntesis , Citidina Desaminasa/genética , Doxiciclina/farmacología , Vectores Genéticos/administración & dosificación , Vectores Genéticos/genética , Células Madre Hematopoyéticas/virología , Humanos , Células K562 , Cultivo Primario de Células , Regiones Promotoras Genéticas , Transgenes
11.
Oncogene ; 34(27): 3593-604, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25241901

RESUMEN

High activation of the PI3K-AKT-mTOR pathway is characteristic for T-cell acute lymphoblastic leukemia (T-ALL). The activity of the master regulator of this pathway, PTEN, is often impaired in T-ALL. However, experimental evidence suggests that input from receptor tyrosine kinases (RTKs) is required for sustained mTOR activation, even in the absence of PTEN. We previously reported the expression of Neurotrophin receptor tyrosine kinases (TRKs) and their respective ligands in primary human leukemia samples. In the present study we aimed to dissect the downstream signaling cascades of TRK-induced T-ALL in a murine model and show that T-ALLs induced by deregulated receptor tyrosine kinase signaling acquire activating mutations in Notch1 and lose PTEN during clonal evolution. Some clones additionally lost one allele of the homeodomain transcription factor Cux1. All events independently led to a gradual hyperactivation of both mTORC1 and mTORC2 signaling. We dissected the role of the individual mTOR complexes by shRNA knockdown and found that the separate depletion of mTORC1 or mTORC2 reduced the growth of T-ALL blasts, but was not sufficient to induce apoptosis. In contrast, knockdown of the mTOR downstream effector eIF4E caused a striking cytotoxic effect, demonstrating a critical addiction to cap-dependent mRNA-translation. Although high mTORC2-AKT activation is commonly associated with drug-resistance, we demonstrate that T-ALL displaying a strong mTORC2-AKT activation were specifically susceptible to 4EGI-1, an inhibitor of the eIF4E-eIF4G interaction. To decipher the mechanism of 4EGI-1, we performed a genome-wide analysis of mRNAs that are translationally regulated by 4EGI-1 in T-ALL. 4EGI-1 effectively reduced the ribosomal occupancy of mRNAs that were strongly upregulated in T-ALL blasts compared with normal thymocytes including transcripts important for translation, mitochondria and cell cycle progression, such as cyclins and ribosomal proteins. These data suggest that disrupting the eIF4E-eIF4G interaction constitutes a promising therapy strategy in mTOR-deregulated T-cell leukemia.


Asunto(s)
Factor 4E Eucariótico de Iniciación/fisiología , Leucemia de Células T/genética , Leucemia de Células T/metabolismo , Complejos Multiproteicos/metabolismo , Biosíntesis de Proteínas , Serina-Treonina Quinasas TOR/metabolismo , Animales , Transformación Celular Neoplásica/genética , Transformación Celular Neoplásica/metabolismo , Regulación Leucémica de la Expresión Génica , Humanos , Diana Mecanicista del Complejo 1 de la Rapamicina , Diana Mecanicista del Complejo 2 de la Rapamicina , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Biosíntesis de Proteínas/genética , Transducción de Señal , Células Tumorales Cultivadas
12.
Gene Ther ; 21(11): 938-49, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25102011

RESUMEN

Retroviral vectors are versatile gene transfer vehicles widely used in basic research and gene therapy. Mutation of retroviral integrase converts these vectors into transient, integration-deficient gene delivery vehicles associated with a high degree of biosafety. We explored the option to use integration-deficient retroviral vectors to achieve transient ectopic expression of transcription factors, which is considered an important tool for induced cell fate conversion. Stepwise optimization of the retroviral episome transfer as exemplified for the transcription factor Oct4 enabled to improve both expression magnitude and endurance. Long terminal repeat-driven γ-retroviral vectors were identified as the most suitable vector architecture. Episomal expression was enhanced by epigenetic modifiers, and Oct4 activity was increased following fusion to a minimal transactivation motif of herpes simplex virus VP16. Based on kinetic analyses, we identified optimal time intervals for repeated vector administration and established prolonged expression windows of choice. Providing proof-of-concept, episomal transfer of Oct4 was potent to mediate conversion of human fibroblasts stably expressing Klf4, Sox2 and c-Myc into induced pluripotent stem cells, which were mainly free of residual Oct4 vector integration. This study provides evidence for suitability of retroviral episome transfer of transcription factors for cell fate conversion, allowing the generation of distinct patient- or disease-specific cell types.


Asunto(s)
Plásmidos/genética , Retroviridae/genética , Factores de Transcripción/genética , Transducción Genética/métodos , Diferenciación Celular/genética , Línea Celular , Vectores Genéticos , Humanos , Células Madre Pluripotentes Inducidas/metabolismo , Integrasas/genética , Factor 4 Similar a Kruppel , Factor 3 de Transcripción de Unión a Octámeros/genética
14.
Gene Ther ; 20(3): 298-307, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22592598

RESUMEN

Regulated transgene expression may reduce transgene-specific and genotoxic risks associated with gene therapy. To prove this concept, we have investigated the suitability of doxycycline (Dox)-inducible human cytidine deaminase (hCDD) overexpression from lentiviral vectors to mediate effective myeloprotection while circumventing the lymphotoxicity observed with constitutive CDD activity. Rapid Dox-mediated transgene induction associated with a 6-17-fold increase in drug resistance was observed in 32D and primary murine bone marrow (BM) cells. Moreover, robust Dox-regulated transgene expression in the entire haematopoietic system was demonstrated for primary and secondary recipients of hCDD-transduced R26-M2rtTA transgenic BM cells. Furthermore, mice were significantly protected from myelosuppressive chemotherapy as evidenced by accelerated recovery of granulocytes (1.9±0.6 vs 1.3±0.3, P=0.034) and platelets (883±194 vs 584±160 10(3) per µl, P=0.011). Minimal transgene expression in the non-induced state and no overt cellular toxicities including lymphotoxicity were detected. Thus, using a relevant murine transplant model our data provide conclusive evidence that drug-resistance transgenes can be expressed in a regulated fashion in the lymphohaematopoietic system, and that Dox-inducible systems may be used to reduce myelotoxic side effect of anticancer chemotherapy or to avoid side effects of high constitutive transgene expression.


Asunto(s)
Citidina Desaminasa/genética , Doxiciclina/farmacología , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Sistema Hematopoyético/metabolismo , Lentivirus/genética , Animales , Western Blotting , Células de la Médula Ósea/efectos de los fármacos , Células de la Médula Ósea/metabolismo , Trasplante de Médula Ósea , Línea Celular , Células Cultivadas , Citarabina/farmacología , Citidina Desaminasa/metabolismo , Relación Dosis-Respuesta a Droga , Femenino , Vectores Genéticos/genética , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Sistema Hematopoyético/citología , Humanos , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Microscopía Fluorescente , Bazo/citología , Bazo/efectos de los fármacos , Bazo/metabolismo , Timo/citología , Timo/efectos de los fármacos , Timo/metabolismo , Imagen de Lapso de Tiempo/métodos , Transgenes/genética
15.
Oncogene ; 32(25): 3028-38, 2013 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-22847614

RESUMEN

Activation of NRas signaling is frequently found in human myeloid leukemia and can be induced by activating mutations as well as by mutations in receptors or signaling molecules upstream of NRas. To study NRas-induced leukemogenesis, we retrovirally overexpressed wild-type NRas in a murine bone marrow transplantation (BMT) model in C57BL/6J mice. Overexpression of wild-type NRas caused myelomonocytic leukemias ∼3 months after BMT in the majority of mice. A subset of mice (30%) developed malignant histiocytosis similar to mice that received mutationally activated NRas(G12D)-expressing bone marrow. Aberrant Ras signaling was demonstrated in cells expressing mutationally active or wild-type NRas, as increased activation of Erk and Akt was observed in both models. However, more NRas(G12D) were found to be in the activated, GTP-bound state in comparison with wild-type NRas. Consistent with observations reported for primary human myelomonocytic leukemia cells, Stat5 activation was also detected in murine leukemic cells. Furthermore, clonal evolution was detected in NRas wild-type-induced leukemias, including expansion of clones containing activating vector insertions in known oncogenes, such as Evi1 and Prdm16. In vitro cooperation of NRas and Evi1 improved long-term expansion of primary murine bone marrow cells. Evi1-positive cells upregulated Bcl-2 and may, therefore, provide anti-apoptotic signals that collaborate with the NRas-induced proliferative effects. As activation of Evi1 has been shown to coincide with NRAS mutations in human acute myeloid leukemia, our murine model recapitulates crucial events in human leukemogenesis.


Asunto(s)
Proteínas de Unión al ADN/metabolismo , Leucemia Mielomonocítica Aguda/metabolismo , Factores de Transcripción/metabolismo , Proteínas ras/metabolismo , Animales , Apoptosis , Trasplante de Médula Ósea , Línea Celular Tumoral , Proliferación Celular , Activación Enzimática , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Genes ras , Humanos , Leucemia Mielomonocítica Aguda/genética , Proteína del Locus del Complejo MDS1 y EV11 , Ratones , Ratones Endogámicos C57BL , Proteínas Proto-Oncogénicas c-akt/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Proto-Oncogenes , Factor de Transcripción STAT5/metabolismo , Transducción de Señal , Proteínas ras/genética
16.
Leukemia ; 27(1): 56-65, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22828445

RESUMEN

The transcriptional regulator ecotropic viral integration site-1 (EVI-1) has mainly been studied for its role in myeloid malignancies, in which high EVI-1 levels are associated with particularly aggressive disease. The role of EVI-1 in lymphoid cells, however, is largely unknown. Here we show that EVI-1 is indeed expressed in lymphoid malignancies such as acute lymphoblastic leukemia (ALL) and a subset of chronic lymphocytic leukemia. Expression data from pediatric ALL further suggest that high EVI-1 levels are associated with poor prognosis. Suppression of EVI-1 expression by RNA interference reduces cell growth and enhances apoptosis sensitivity in response to various stimuli in lymphoblastic leukemia cells. At the molecular level, EVI-1 modulates expression of several apoptosis-related genes (such as BCL2, BCL-x, XIAP, NOXA, PUMA, TRAIL-R1). Furthermore, EVI-1 knockdown strongly impairs in vivo engraftment of lymphoblastic leukemia cells upon transplantation in immune-permissive NOD/SCID/IL2Rγ(null) mice, conferring a survival benefit when compared with mice transplanted with control cells. Thus, our data show that EVI-1 is expressed not only in myeloid but also in lymphoid leukemias, and contributes to the leukemogenic potential and apoptosis resistance of ALL cells.


Asunto(s)
Apoptosis , Proteínas de Unión al ADN/metabolismo , Leucemia Linfocítica Crónica de Células B/patología , Leucemia Mieloide Aguda/patología , Leucemia-Linfoma Linfoblástico de Células Precursoras/patología , Factores de Transcripción/metabolismo , Adulto , Animales , Western Blotting , Estudios de Casos y Controles , Ciclo Celular , Proliferación Celular , Niño , Proteínas de Unión al ADN/antagonistas & inhibidores , Proteínas de Unión al ADN/genética , Técnica del Anticuerpo Fluorescente , Humanos , Subunidad gamma Común de Receptores de Interleucina/fisiología , Leucemia Linfocítica Crónica de Células B/genética , Leucemia Linfocítica Crónica de Células B/metabolismo , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Proteína del Locus del Complejo MDS1 y EV11 , Ratones , Ratones Endogámicos NOD , Ratones SCID , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Proto-Oncogenes/genética , ARN Interferente Pequeño/genética , Factores de Transcripción/antagonistas & inhibidores , Factores de Transcripción/genética , Células Tumorales Cultivadas
17.
Leukemia ; 27(5): 1127-38, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23212151

RESUMEN

The transcription factor Evi1 has an outstanding role in the formation and transformation of hematopoietic cells. Its activation by chromosomal rearrangement induces a myelodysplastic syndrome with progression to acute myeloid leukemia of poor prognosis. Similarly, retroviral insertion-mediated upregulation confers a competitive advantage to transplanted hematopoietic cells, triggering clonal dominance or even leukemia. To study the molecular and functional response of primary murine hematopoietic progenitor cells to the activation of Evi1, we established an inducible lentiviral expression system. EVI1 had a biphasic effect with initial growth inhibition and retarded myeloid differentiation linked to enhanced survival of myeloblasts in long-term cultures. Gene expression microarray analysis revealed that within 24 h EVI1 upregulated 'stemness' genes characteristic for long-term hematopoietic stem cells (Aldh1a1, Abca1, Cdkn1b, Cdkn1c, Epcam, among others) but downregulated genes involved in DNA replication (Cyclins and their kinases, among others) and DNA repair (including Brca1, Brca2, Rad51). Cell cycle analysis demonstrated EVI1's anti-proliferative effect to be strictly dose-dependent with accumulation of cells in G0/G1, but preservation of a small fraction of long-term proliferating cells. Although confined to cultured cells, our study contributes to new hypotheses addressing the mechanisms and molecular targets involved in preleukemic clonal dominance or leukemic transformation by Evi1.


Asunto(s)
Ciclo Celular , Proteínas de Unión al ADN/fisiología , Células Madre Hematopoyéticas/citología , Proto-Oncogenes/fisiología , Factores de Transcripción/fisiología , Animales , Diferenciación Celular , Línea Celular , Supervivencia Celular , Células Precursoras de Granulocitos/fisiología , Humanos , Proteína del Locus del Complejo MDS1 y EV11 , Ratones , Ratones Endogámicos C57BL
19.
Gene Ther ; 19(1): 15-24, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21562592

RESUMEN

Gene transfer-based therapeutic approaches have greatly benefited from the ability of some viral vectors to efficiently integrate within the cell genome and ensure persistent transmission of newly acquired transgenes to the target cell progeny. However, integration of provirus has been associated with epigenetic repercussions that may influence the expression of both the transgene and cellular genes close to vector integration loci. The exploitation of genetic insulator elements may overcome both issues through their ability to act as barriers that limit transgene silencing and/or as enhancer-blockers preventing the activation of endogenous genes by the vector enhancer. We established quantitative plasmid-based assay systems to screen enhancer-blocker and barrier genetic elements. Short synthetic insulators that bind to nuclear factor-I protein family transcription factors were identified to exert both enhancer-blocker and barrier functions, and were compared to binding sites for the insulator protein CTCF (CCCTC-binding factor). Gamma-retroviral vectors enclosing these insulator elements were produced at titers similar to their non-insulated counterparts and proved to be less genotoxic in an in vitro immortalization assay, yielding lower activation of Evi1 oncogene expression and reduced clonal expansion of bone marrow cells.


Asunto(s)
Técnicas de Transferencia de Gen , Vectores Genéticos/metabolismo , Elementos Aisladores , Factores de Transcripción NFI/metabolismo , Animales , Sitios de Unión , Células de la Médula Ósea/citología , Células de la Médula Ósea/metabolismo , Factor de Unión a CCCTC , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Elementos de Facilitación Genéticos , Virus de la Leucemia Murina de Friend/genética , Virus de la Leucemia Murina de Friend/metabolismo , Silenciador del Gen , Vectores Genéticos/genética , Células HeLa , Humanos , Proteína del Locus del Complejo MDS1 y EV11 , Ratones , Ratones Endogámicos C57BL , Factores de Transcripción NFI/genética , Plásmidos/genética , Plásmidos/metabolismo , Proto-Oncogenes/genética , ARN Interferente Pequeño/genética , ARN Interferente Pequeño/metabolismo , Proteínas Represoras/genética , Proteínas Represoras/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Activación Transcripcional , Transfección , Transgenes , Integración Viral
20.
J Anim Sci ; 90 Suppl 4: 212-4, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23365333

RESUMEN

Two studies, arranged according to a 4 × 4 Latin square design, were conducted to assess effects of dietary acidification on fungal 3-phytase (PHY) efficacy in growing pigs. In Exp. 1, effects of supplementing 500 units/kg feed of PHY and 4.7 g/kg HCOOH either alone or in combination on the use of P and Zn in growing pigs fed a pelleted diet based on wheat (Triticum aestivum), barley (Hordeum vulgare), and soybean (Glycine max) meal were investigated. In Exp. 2 the same dietary treatments were fed except that PHY supplementation was increased to 1000 units/kg. In both experiments, PHY supplementation increased (P < 0.05) P digestibility and retention. A PHY × HCOOH supplementation interaction on P balance was observed (P < 0.05), indicating that the combination of the additives may increase P digestibility and retention. Effects of HCOOH and PHY on Zn use followed a similar pattern. Supplementation of 1000 units/kg of PHY further increased P and Zn retention compared to supplementation of 500 units/kg. In conclusion, the present study indicated that HCOOH supplementation to diets with microbial PHY may increase PHY efficacy.


Asunto(s)
6-Fitasa/farmacología , Digestión/efectos de los fármacos , Formiatos/farmacología , Fósforo/metabolismo , Porcinos/fisiología , Zinc/metabolismo , Alimentación Animal/análisis , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Dieta/veterinaria , Suplementos Dietéticos , Digestión/fisiología , Heces/química , Masculino
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