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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
2.
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
3.
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
4.
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
5.
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
6.
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
7.
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
8.
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
9.
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
10.
Gene Ther ; 19(4): 425-34, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21850050

RESUMEN

Partial resistance of primary mouse hepatocytes to lentiviral (LV) vector transduction poses a challenge for ex vivo gene therapy protocols in models of monogenetic liver disease. We thus sought to optimize ex vivo LV gene transfer while preserving the hepatocyte integrity for subsequent transplantation into recipient animals. We found that culture media supplemented with epidermal growth factor (EGF) and, to a lesser extent, hepatocyte growth factor (HGF) markedly improved transduction efficacy at various multiplicities of infection. Up to 87% of primary hepatocytes were transduced in the presence of 10 ng EGF, compared with ~30% in standard culture medium (SCMs). The increased number of transgene-expressing cells correlated with increased nuclear import and more integrated pro-viral copies per cell. Higher LV transduction efficacy was not associated with proliferation, as transduction capacity of gammaretroviral vectors remained low (<1%). Finally, we developed an LV transduction protocol for short-term (maximum 24 h) adherent hepatocyte cultures. LV-transduced hepatocytes showed liver repopulation capacities similar to freshly isolated hepatocytes in alb-uPA mouse recipients. Our findings highlight the importance of EGF for efficient LV transduction of primary hepatocytes in culture and should facilitate studies of LV gene transfer in mouse models of monogenetic liver disease.


Asunto(s)
Factor de Crecimiento Epidérmico/farmacología , Vectores Genéticos , Hepatocitos/metabolismo , Lentivirus/genética , Transducción Genética , Animales , Células Cultivadas , Medios de Cultivo , Técnicas de Transferencia de Gen , Factor de Crecimiento de Hepatocito/farmacología , Hepatocitos/trasplante , Ratones , Ratones Endogámicos C57BL
11.
Gene Ther ; 19(3): 246-54, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21753795

RESUMEN

The need for γ-retroviral (gRV) vectors with a self-inactivating (SIN) design for clinical application has prompted a shift in methodology of vector manufacturing from the traditional use of stable producer lines to transient transfection-based techniques. Herein, we set out to define and optimize a scalable manufacturing process for the production of gRV vectors using transfection in a closed-system bioreactor in compliance with current good manufacturing practices (cGMP). The process was based on transient transfection of 293T cells on Fibra-Cel disks in the Wave Bioreactor. Cells were harvested from tissue culture flasks and transferred to the bioreactor containing Fibra-Cel in the presence of vector plasmid, packaging plasmids and calcium-phosphate in Dulbecco's modified Eagle's medium and 10% fetal bovine serum. Virus supernatant was harvested at 10-14 h intervals. Using optimized procedures, a total of five ecotropic cGMP-grade gRV vectors were produced (9 liters each) with titers up to 3.6 × 10(7) infectious units per milliliter on 3T3 cells. One GMP preparation of vector-like particles was also produced. These results describe an optimized process for the generation of SIN viral vectors by transfection using a disposable platform that allows for the generation of clinical-grade viral vectors without the need for cleaning validation in a cost-effective manner.


Asunto(s)
Reactores Biológicos , Gammaretrovirus/genética , Vectores Genéticos/aislamiento & purificación , Vectores Genéticos/normas , Transfección/métodos , Animales , Técnicas de Cultivo Celular por Lotes/métodos , Técnicas de Cultivo Celular por Lotes/normas , Biotecnología , Línea Celular , Gammaretrovirus/aislamiento & purificación , Humanos , Ratones , Control de Calidad
12.
Gene Ther ; 17(3): 400-11, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19847204

RESUMEN

Bidirectional lentiviral vectors mediate expression of two or more cDNAs from a single internal promoter. In this study, we examined mechanisms that control titer and expression properties of this vector system. To address whether the bidirectional design depends on lentiviral (LV) backbone components, especially the Rev/Rev responsive element (RRE) system, we constructed similar expression cassettes for LV and gammaretroviral (GV) vectors. Bidirectional expression levels could be adjusted by the use of different internal promoters. Furthermore, removal of the constitutive RNA transport element of Mason-Pfizer monkey virus, used in first generation bidirectional LV vectors, improved gene expression. Titers of bidirectional vectors were approximately 10-fold reduced in comparison to unidirectional vectors, independent of the Rev/RRE interaction. We reasoned that titer reductions were due to the formation of interfering double-stranded RNA in packaging cells. Indeed, cotransfection of Nodamuravirus B2 protein, an RNA interference suppressor, increased bidirectional vector titers at least fivefold. We validated the potential of high titer bidirectional vectors by coexpressing a fluorescent marker with O(6)-methylguanine-DNA methyltransferase from integrating, or with Cre recombinase from integrating and non-integrating GV and LV backbones. This allowed for the tracking of chemoprotected and recombined cells by fluorescence marker expression.


Asunto(s)
Gammaretrovirus/genética , Regulación Viral de la Expresión Génica , Vectores Genéticos/genética , Lentivirus/genética , Carga Viral/genética , Animales , Línea Celular , Genes env , Humanos , Virus del Mono Mason-Pfizer/genética , Ratones , O(6)-Metilguanina-ADN Metiltransferasa/genética , Regiones Promotoras Genéticas , ARN Bicatenario/genética
13.
Gene Ther ; 17(2): 272-80, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19865181

RESUMEN

The clinical application of self-inactivating (SIN) retroviral vectors has been hampered by the lack of reliable and efficient vector production technologies. To enable production of SIN gamma-retroviral vectors from stable producer clones, a new PG13-based packaging cell, known as PG368, was developed. Viral vector expression constructs can be reliably inserted at a predefined genomic locus of PG368 packaging cells by an Flp-recombinase-mediated targeted cassette exchange (RMCE) reaction. A new, carefully designed vector-targeting construct, pEMTAR-1, eliminated the co-packaging of the selectable marker gene used for the identification of successful recombination at the predefined genomic locus and thus, improved the safety of the production system. Selected clones produced vector supernatants at consistent titers. The targeted insertion of therapeutically relevant SIN vectors for chronic granulomatous disease and X-linked severe combined immunodeficiency into PG368 cells results in stable titers within the range necessary for clinical application. The production of retroviral SIN vectors from stable clinical-grade producer cells is feasible and will contribute to the safe production and application of SIN gamma-retroviral vectors for clinical trials.


Asunto(s)
ADN Nucleotidiltransferasas , Técnicas de Transferencia de Gen , Vectores Genéticos , Retroviridae/genética , Línea Celular , Estudios de Factibilidad , Marcación de Gen , Terapia Genética/métodos , Enfermedad Granulomatosa Crónica/terapia , Humanos , Inmunodeficiencia Combinada Grave/terapia
14.
J Exp Med ; 162(1): 282-96, 1985 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-3159826

RESUMEN

Analysis of mouse IgG binding to Fc receptors on mouse B cells indicates that the IgG1, IgG2a, and IgGb subclasses bind to the same receptor. No differences in affinity were detected among subclass or between mouse strains. This same receptor bound rat IgG with an affinity that differed between mouse strains. This polymorphism in affinity for rat IgG maps to chromosome 12 distal to the Igh locus.


Asunto(s)
Linfocitos B/inmunología , Cadenas Pesadas de Inmunoglobulina/genética , Polimorfismo Genético , Receptores Fc/genética , Animales , Mapeo Cromosómico , Genes , Ligamiento Genético , Inmunoglobulina G/metabolismo , Ratones , Ratones Endogámicos , Receptores Fc/metabolismo , Receptores de IgG , Recombinación Genética
15.
J Exp Med ; 174(5): 1283-6, 1991 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-1719121

RESUMEN

The search for human hematopoietic stem cells has been hampered by the lack of appropriate assay systems. Demonstration of the ability of precursor cell candidates to give rise to T cells is of significant difficulty since dissociated in vitro cultured thymus stroma cells lose their ability to sustain thymocyte maturation. To define further the differentiative capacities of the rare human fetal liver and bone marrow cells that express the CD34 surface antigen and exhibit in vitro myeloid and pre-B cell activities, we have microinjected them into HLA-mismatched fetal thymus fragments, partially depleted of hematopoietic cells by low temperature culture. In vitro colonized thymuses have then been allowed to develop upon engraftment into immunodeficient SCID mice. Using this modification of the SCID-hu system, we show that low numbers of fetal CD34+ progenitor cells can repopulate the lymphoid compartment in the human thymus.


Asunto(s)
Antígenos CD/análisis , Feto/inmunología , Células Madre Hematopoyéticas/fisiología , Ratones SCID/inmunología , Linfocitos T/fisiología , Timo/citología , Animales , Antígenos CD34 , Médula Ósea/fisiología , Humanos , Ratones , Técnicas de Cultivo de Órganos , Reacción en Cadena de la Polimerasa
16.
Gene Ther ; 16(1): 111-8, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18784749

RESUMEN

Gene therapy has proven to be of potential value for the correction of inherited hematopoietic disorders. However, the occurrence of severe side effects in some of the clinical trials has questioned the safety of this approach and has hampered the use of long terminal repeat-driven vectors for the treatment of a large number of patients. The development of self-inactivating (SIN) vectors with reduced genotoxicity provides an alternative to the currently used vectors. Our initial attempts to use SIN vectors for the correction of a myeloid disorder, chronic granulomatous disease, failed due to low vector titers and poor transgene expression. The optimization of the transgene cDNA (gp91(phox)) resulted in substantially increased titers and transgene expression. Most notably, transgene optimization significantly improved expression of a second cistron located downstream of gp91(phox). Thus, optimization of the transgene sequence results in higher expression levels and increased therapeutic index allowing the use of low vector copy numbers per transduced cell and weaker internal promoters.


Asunto(s)
Terapia Genética/métodos , Enfermedad Granulomatosa Crónica/terapia , Células Madre Hematopoyéticas/metabolismo , Glicoproteínas de Membrana/genética , NADPH Oxidasas/genética , Animales , Línea Celular Tumoral , Expresión Génica , Vectores Genéticos/administración & dosificación , Vectores Genéticos/genética , Enfermedad Granulomatosa Crónica/metabolismo , Células Madre Hematopoyéticas/virología , Humanos , Separación Inmunomagnética , Glicoproteínas de Membrana/metabolismo , Ratones , Ratones Noqueados , NADPH Oxidasa 2 , NADPH Oxidasas/metabolismo , Retroviridae/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Superóxidos/análisis , Transducción Genética/métodos , Transgenes , Inactivación de Virus
17.
Handb Exp Pharmacol ; (189): 265-97, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19048204

RESUMEN

This chapter describes the major gene therapeutic approaches for viral infections. The vast majority of published approaches target severe chronic viral infections such as hepatitis B or C and HIV infection. Two basic gene therapy strategies are introduced here. The first involves the expression of a protein or an RNA that inhibits viral replication by targeting crucial steps of the viral life cycle or by interfering with a cellular factor required for virus replication. The major limitation of this approach is that primary levels of gene modification have generally not been sufficient to reduce the availability of target cells permissive for virus replication to a level that significantly decreases overall viral load. Thus, investigators have banked on the expectation that gene-protected cells have a sufficient selective advantage to accumulate and gain prevalence over time, a prediction that so far could not be confirmed in clinical trials. In vivo levels of gene modification can be improved, however, by introducing an additional selectable marker. In addition, a secreted antiviral gene product that exerts a bystander effect could significantly reduce overall virus replication despite relatively low levels of gene modification. In addition to these direct antiviral approaches, several strategies have been developed that employ or aim to enhance host immune responses. The innate immune response has been enhanced, for example, by the in vivo expression of interferons. Alternatively, T cells can be grafted with recombinant receptors to boost adaptive virus-specific immunity. These approaches are especially promising for chronic virus infection, where natural immune responses are evidently not sufficient to effectively control virus replication.


Asunto(s)
Terapia Genética , Virosis/terapia , Virus/genética , Traslado Adoptivo , Animales , Ensayos Clínicos como Asunto , Marcadores Genéticos , Vectores Genéticos/química , Humanos , Inmunidad/genética , Inmunidad/fisiología , Linfocitos T/inmunología , Virosis/genética , Replicación Viral/efectos de los fármacos
19.
Artículo en Alemán | MEDLINE | ID: mdl-19626282

RESUMEN

The medical doctorate and the subsequent advanced research qualification in medicine have an exceptional position within the natural sciences. While, in the German system, graduation to the degree of a medical doctor is often an initiation into scientific practice, the in-depth scientific education of medical doctors may be achieved in various configurations. In recent years, structured programs for doctorates in medicine and natural sciences have found increasing acceptance, following recommendations of national scientific councils ("Deutsche Forschungsgemeinschaft" and "Hochschulrat"). Hannover Medical School has been offering such programs for a number of years. The StrucMed program increases the quality of medical doctorate studies, typically performed in the third and fourth years of university studies. The Hannover Biomedical Research School (HBRS) combines several programs for a doctorate in natural sciences, creating a platform for an internationally oriented education of post-graduates in various disciplines of life sciences. Evaluating the achievements and career paths of the trainees will contribute to the successful integration of research work in an efficiency-oriented clinical environment.


Asunto(s)
Disciplinas de las Ciencias Biológicas/educación , Selección de Profesión , Movilidad Laboral , Educación de Postgrado en Medicina/organización & administración , Investigación/educación , Curriculum , Alemania , Humanos , Garantía de la Calidad de Atención de Salud
20.
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.

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