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Social relationships change across the lifespan as social networks narrow and motivational priorities shift to the present. Interestingly, aging is also associated with changes in executive function, including decision-making abilities, but it remains unclear how age-related changes in both domains interact to impact financial decisions involving other people. To study this problem, we recruited 50 human participants (Nyounger = 26, ages 18-34; Nolder = 24, ages 63-80) to play an economic trust game as the investor with three partners (friend, stranger, and computer) who played the role of investee. Investors underwent functional magnetic resonance imaging (fMRI) during the trust game while investees were seated outside of the scanner. Building on our previous work with younger adults showing both enhanced striatal responses and altered default-mode network (DMN) connectivity as a function of social closeness during reciprocated trust, we predicted that these relations would exhibit age-related differences. We found that striatal responses to reciprocated trust from friends relative to strangers and computers were blunted in older adults relative to younger adults, thus supporting our primary pre-registered hypothesis regarding social closeness. We also found that older adults exhibited enhanced DMN connectivity with the temporoparietal junction (TPJ) during reciprocated trust from friends compared to computers while younger adults exhibited the opposite pattern. Taken together, these results advance our understanding of age-related differences in sensitivity to social closeness in the context of trusting others.
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Red en Modo Predeterminado , Estriado Ventral , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Mapeo Encefálico , Red en Modo Predeterminado/diagnóstico por imagen , Función Ejecutiva , Humanos , Imagen por Resonancia Magnética , Persona de Mediana Edad , Confianza , Estriado Ventral/diagnóstico por imagen , Adulto JovenRESUMEN
We used a GIS analysis of sodium and chloride concentrations in private water wells in a southeastern New York township to describe the pattern of distribution of road salt in aquifers tapped for drinking water. The primary source of road salt was sodium chloride, and sodium and chloride concentrations were significantly correlated ( = 0.80, < 0.01). Chloride concentrations in wells increased as the percentage of impervious surface cover (ISC) within a 250-m radius around wells increased ( = 0.87, < 0.01) and declined with increasing distance to the nearest road ( = 0.76, < 0.01). Wells that were located lower in elevation than the nearest road had higher concentrations of chloride than wells that were higher than the nearest road, but this occurred only when the nearest road was >30 m from the wells ( < 0.01). Chloride concentrations were not affected by well depth or adjacent road type (major or minor roads). Surface geology and hydrologic soil class had significant effects ( < 0.01) on chloride concentrations in wells, with porous surface geology types and well-drained soils having higher concentrations; these effects may be confounded by the fact that ISC was more likely to occur on these permeable surface geology and soil types. Hot and cold spot analysis revealed substantial unevenness in chloride concentrations. Results for sodium were similar to those for chloride. Overall, these results indicate that road salt contamination of groundwater is unevenly distributed and is affected by landscape factors that can be used to guide well testing and best management practices of deicing salt distribution.
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Agua Potable , Cloruro de Sodio/análisis , Contaminantes Químicos del Agua/análisis , Monitoreo del Ambiente , New YorkRESUMEN
A new wave of emerging therapies for the treatment of autoimmune and inflammatory diseases is under development. These therapies interrupt intracellular signalling through kinase inhibition. By interrupting one or more kinases it is possible to modulate the function of cellular structures such as surface receptors, signalling proteins and transcription of nuclear proteins and thus influence the behaviour of the cell types targeted. With these advances comes the significant potential to develop highly effective orally bioavailable therapeutics. The targets generating the greatest enthusiasm at this time for the treatment of autoimmune and inflammatory diseases include Janus-associated kinase, spleen tyrosine kinase, phosphodiesterase-4, Bruton's tyrosine kinase and phosphatidylinositol-3 kinase. Ultimately human trials will help us understand the potential risks and benefits of these novel approaches across a number of diseases.
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Artritis Reumatoide/tratamiento farmacológico , Inhibidores de Proteínas Quinasas/uso terapéutico , Agammaglobulinemia Tirosina Quinasa , Fosfatidilinositol 3-Quinasas Clase II , Humanos , Péptidos y Proteínas de Señalización Intracelular/antagonistas & inhibidores , Quinasas Janus/antagonistas & inhibidores , Inhibidores de Fosfodiesterasa 4 , Inhibidores de las Quinasa Fosfoinosítidos-3 , Proteínas Tirosina Quinasas/antagonistas & inhibidores , Quinasa SykRESUMEN
PURPOSE: Although speech-language pathologists have provided gender-affirming voice training for trans women since the 1970s, evidence for this training's effectiveness remains weak. Our study aimed to redress limitations of earlier studies and evaluate voice training effects on outcomes important to trans women. METHOD: Seventy-four trans women (19-54 years old) who wanted a more female-sounding voice were recruited through two health facilities and provided with an eight- to 12-session voice training program based on contemporary literature, usual clinical practice, and client-centered care principles. Self-reported outcomes and an audio-recorded reading sample were collected 3 months before, immediately before and after, and 3 months after training. Forty cisgender speakers were audio-recorded reading the same sample material as comparison voices. Seventy-nine naive listeners made gender-related voice ratings of an extract from these audio recordings. Training effectiveness was evaluated using group-level analyses (linear mixed-effects models) and individual-level analyses to establish what proportion of participants improved to a predetermined relevant degree. RESULTS: Group-level analyses demonstrated positive training effects, maintained 3 months posttraining, for trans women's vocal satisfaction, perceptions of voice-related social participation, and self- and listener perceptions of their voices. Individual-level analyses also demonstrated positive effects. Two thirds of trans women increased vocal satisfaction to a relevant degree, one third who reported restricted social participation before training reduced this restriction to a relevant degree, and all were rated more female-sounding after training (although not all to a relevant degree). CONCLUSIONS: All trans women participants made progress toward their voice goals and maintained those gains at follow-up. These findings provide evidence that gender-affirming speech-language pathology services warrant prioritization. Further research is warranted to investigate factors predicting outcomes of voice training for trans women.
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Transexualidad , Voz , Humanos , Femenino , Adulto Joven , Adulto , Persona de Mediana Edad , Entrenamiento de la Voz , Identidad de Género , Medición de Resultados Informados por el PacienteRESUMEN
Tumor evolution from a single cell into a malignant, heterogeneous tissue remains poorly understood. Here, we profile single-cell transcriptomes of genetically engineered mouse lung tumors at seven stages, from pre-neoplastic hyperplasia to adenocarcinoma. The diversity of transcriptional states increases over time and is reproducible across tumors and mice. Cancer cells progressively adopt alternate lineage identities, computationally predicted to be mediated through a common transitional, high-plasticity cell state (HPCS). Accordingly, HPCS cells prospectively isolated from mouse tumors and human patient-derived xenografts display high capacity for differentiation and proliferation. The HPCS program is associated with poor survival across human cancers and demonstrates chemoresistance in mice. Our study reveals a central principle underpinning intra-tumoral heterogeneity and motivates therapeutic targeting of the HPCS.
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Plasticidad de la Célula/genética , Células Epiteliales/metabolismo , Transición Epitelial-Mesenquimal/genética , Neoplasias Pulmonares/genética , Células Madre Neoplásicas/metabolismo , Animales , Diferenciación Celular/genética , Línea Celular Tumoral , Proliferación Celular/genética , Células Cultivadas , Modelos Animales de Enfermedad , Células Epiteliales/citología , Heterogeneidad Genética , Humanos , Neoplasias Pulmonares/patología , Ratones , Análisis de la Célula Individual/métodos , Transcriptoma/genéticaRESUMEN
OBJECTIVES: Transgender women often seek to feminize their voice so that it becomes congruent with their gender identity. Many receive voice therapy (VT) with good results. Some also need pitch-raising surgery. The purpose of this study was to investigate long-term effects and to compare outcomes between cricothyroid approximation (CTA) and glottoplasty (GP). METHODS: This study included retrospective data from 24 patients (35-67 years). Eleven patients had undergone CTA and 13 had undergone GP. Audio recordings were performed in a sound-treated booth and patients answered questionnaires before and after VT, post surgery, and at 1-year follow-up. Fundamental frequency (fo) measures were extracted from voice range profiles (VRPs) and speech range profiles (SRPs) and were compared with cisgender data. RESULTS: Minimum fo in VRP increased significantly only after CTA (95 to 123 Hz). Maximum fo in VRP was significantly lowered after GP (765 to 652 Hz), even more after CTA (677 to 475 Hz). Speaking mean fo increased significantly after VT and post surgery, and was thereafter stable (CTA 167 Hz, GP 169 Hz). The maximum fo in the SRP increased only after VT. The frequency ranges were strongly reduced after CTA. Patients were in general satisfied at follow-up and rated the GP outcomes more favorably than CTA. CONCLUSIONS: Both surgical methods have advantages and disadvantages. The very restricted speaking and physiological frequency ranges, which do not favor an optimal female voice, were mainly found after the irreversible CTA. Thus, CTA is no longer performed at our hospital, whereas surgical techniques based on GP are being developed further. We strongly recommend the use of VRPs to evaluate treatment effects.
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Laringe/cirugía , Procedimientos Quirúrgicos Otorrinolaringológicos , Acústica del Lenguaje , Personas Transgénero , Voz , Adulto , Anciano , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Medición de Resultados Informados por el Paciente , Estudios RetrospectivosRESUMEN
We assessed the ability of preschool children to assign the most difficult tasks to a symbolic helper. First, children were taught that a toy "helper" could aid them in remembering the location of a hidden item. Children preferentially assigned the helper to the objectively most difficult locations to remember. Each child then completed eight more tests, assessing a range of different skills such as counting, object identification, and word reading. Children again could assign some stimuli in each task to the helper, leaving the remaining stimuli for themselves to respond to in the given tasks. They were not explicitly told to assign the hardest stimulus to the helper. However, children consistently still did so in most tasks, although some tasks showed an effect of age where older children were more proficient in assigning the objectively more difficult stimuli to the helper. These results highlight a potential form of metacognition in young children in which they can monitor difficulty across varied kinds of assessments and use a generalized tool for asking for help that does not require verbal responding.
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Recuerdo Mental/fisiología , Metacognición/fisiología , Niño , Preescolar , Femenino , Humanos , MasculinoRESUMEN
OBJECTIVE: This investigation comprehensively assessed the technology use, preferences, and capacity of diverse injured trauma survivors with posttraumatic stress disorder (PTSD) symptoms. METHOD: A total of 121 patients participating in a randomized clinical trial (RCT) of stepped collaborative care targeting PTSD symptoms were administered baseline one-, three-, and six-month interviews that assessed technology use. Longitudinal data about the instability of patient cell phone ownership and phone numbers were collected from follow-up interviews. PTSD symptoms were also assessed over the course of the six months after injury. Regression analyses explored the associations between cell phone instability and PTSD symptoms. RESULTS: At baseline, 71.9% (n = 87) of patients reported current cell phone ownership, and over half (58.2%, n = 46) of these patients possessed basic cell phones. Only 19.0% (n = 23) of patients had no change in cell phone number or physical phone over the course of the six months postinjury. In regression models that adjusted for relevant clinical and demographic characteristics, cell phone instability was associated with higher six-month postinjury PTSD symptom levels (p < 0.001). CONCLUSIONS: Diverse injured patients at risk for the development of PTSD have unique technology use patterns, including high rates of cell phone instability. These observations should be strongly considered when developing technology-supported interventions for injured patients with PTSD.
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Teléfono Celular/estadística & datos numéricos , Aplicaciones Móviles/estadística & datos numéricos , Prioridad del Paciente/estadística & datos numéricos , Teléfono Inteligente/estadística & datos numéricos , Trastornos por Estrés Postraumático/epidemiología , Sobrevivientes/estadística & datos numéricos , Heridas y Lesiones/epidemiología , Adulto , Femenino , Estudios de Seguimiento , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Trastornos por Estrés Postraumático/etiología , Heridas y Lesiones/complicacionesAsunto(s)
Aneurisma Falso/diagnóstico , Duodeno/irrigación sanguínea , Pancreatitis Alcohólica/complicaciones , Estómago/irrigación sanguínea , Dolor Abdominal/etiología , Aneurisma Falso/diagnóstico por imagen , Aneurisma Falso/etiología , Aneurisma Falso/terapia , Embolización Terapéutica , Dilatación Gástrica/etiología , Obstrucción de la Salida Gástrica/etiología , Humanos , Masculino , Persona de Mediana Edad , Pancreatitis Alcohólica/diagnóstico por imagen , Tomografía Computarizada por Rayos XRESUMEN
Ammonium (NH(4)(+)) concentrations in air and precipitation at the Institute of Ecosystem Studies (IES) in southeastern New York, USA declined over an 11-year period from 1988 to 1999, but increased from 1999 to 2001. These trends in particulate NH(4)(+) correlated well with trends in particulate SO(4)(2-) over the 1988-2001 period. The NH(4)(+) trends were not as well correlated with local cattle and milk production, which declined continuously throughout the period. This suggests that regional transport of SO(4)(2-) may have a greater impact on concentrations of NH(4)(+) and subsequent deposition than local agricultural emissions of NH(3). Ammonium concentrations in precipitation correlated significantly with precipitation SO(4)(2-) concentrations for the 1984-2001 period although NH(4)(+) in precipitation increased after 1999 and SO(4)(2-) in precipitation continued to decline after 1999. The correlation between NH(4)(+) and SO(4)(2-) was stronger for particulates than for precipitation. Particulate NH(4)(+) concentrations were also correlated with particulate SO(4)(2-) concentrations at 31 of 35 eastern U.S. CASTNet sites that had at least 10 years of data. Air concentrations of NH(4)(+) and SO(4)(2-) were more strongly correlated at the sites that were located within an agricultural landscape than in forested sites. At most of the sites there was either no trend or a decrease in NH(4)(+) dry deposition during the 1988-2001 period. The sites that showed an increasing trend in NH(4)(+) dry deposition were generally located in the southeastern U.S. The results of this study suggest that, in the northeastern U.S., air concentrations of NH(4)(+) and subsequent deposition may be more closely linked to SO(4)(2-) and thus SO(2) emissions than with NH(3) emissions. These results also suggest that reductions in S emissions have reduced NH(4)(+) transport to and NH(4)(+)-N deposition in the Northeast.
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Agricultura , Contaminantes Atmosféricos/análisis , Atmósfera/análisis , Compuestos de Amonio Cuaternario/análisis , Sulfatos/análisis , Animales , Bovinos , Precipitación Química , Monitoreo del Ambiente/métodos , Leche , New YorkRESUMEN
Integrin signaling relies on multiple, distinct pathways to impact a diverse set of cell behaviors. The Rho family of GTPases are well-established downstream signaling partners of integrins that regulate cell shape, polarity, and migration. The nematode C. elegans provides a simple in vivo system for studying both integrins and the Rho family. Our previous work showed that the C. elegans α integrin cytoplasmic tails have tissue-specific functions during development. Here, we use chimeric α integrins to show that the cytoplasmic tails can rescue the loss of the Rho family of GTPases in three cell types in the somatic gonad. Knockdown of rho-1 by RNAi causes defects in sheath cell actin organization, ovulation, and vulva morphology. Chimeric α integrin ina-1 with the pat-2 cytoplasmic tail can rescue both actin organization and ovulation after rho-1 RNAi, yet cannot restore vulva morphology. Knockdown of cdc-42 by RNAi causes defects in sheath cell actin organization, ovulation, vulva morphology, and distal tip cell migration. Chimeric α integrin pat-2 with the ina-1 cytoplasmic tail can rescue vulva morphology defects and distal tip cell migration after cdc-42 RNAi, yet cannot restore sheath cell actin organization or ovulation. Disruption of Rac yields the same phenotype in distal tip cells regardless of α integrin cytoplasmic tail composition. Taken together, the cytoplasmic tails of α integrins can bypass signaling from members of the Rho family of GTPases during development.
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Proteínas de Caenorhabditis elegans/metabolismo , Gónadas/metabolismo , Cadenas alfa de Integrinas/metabolismo , Transducción de Señal/genética , Proteínas de Unión al GTP rho/metabolismo , Actinas/metabolismo , Animales , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Movimiento Celular/genética , Femenino , Cadenas alfa de Integrinas/genética , Ovulación/genética , Ovulación/metabolismo , Interferencia de ARN , Proteínas de Unión al GTP rho/genéticaAsunto(s)
Mastocitosis Cutánea/diagnóstico , Preescolar , Femenino , Humanos , Lactante , Mastocitoma Cutáneo/complicaciones , Mastocitoma Cutáneo/diagnóstico , Mastocitosis Cutánea/complicaciones , Examen Físico/métodos , Urticaria Pigmentosa/complicaciones , Urticaria Pigmentosa/diagnóstico , Heridas y Lesiones/complicacionesRESUMEN
Biorepository processing includes nucleic acid extractions in batch mode from a large number of blood samples from many different donors. Handling such a large number of biospecimens presents the challenge of ensuring that samples are not switched or mislabeled during processing. One approach for confirming donor identity from DNA samples is the use of multiplexed fluorescent PCR for detecting Short Tandem Repeat (STR) allelic-size polymorphisms for a set of common autosomal loci. While donor identity of DNA extracted directly from blood collected in standard tubes containing anticoagulants can be easily verified by generating STR profiles, RNA from blood collected in PAXgene Blood RNA tubes (PAXgene RNA tubes) is depleted of DNA and is not amenable to STR fingerprinting for donor identity verification. We investigated the feasibility of isolating DNA directly from blood collected in PAXgene RNA tubes for use as template for STR DNA fingerprinting for blood donor identity verification. We determined that DNA extraction can be performed manually with the QIAamp DNA Blood Minikit or on the QIAxtractor instrument with minimal pre-processing protocol additions, and that DNA isolated from blood collected in PAXgene RNA tubes is of sufficient quantity and quality for successful STR fingerprint analysis. Adaptation of quality assurance methods such as the PAXgene RNA tube DNA extraction/STR fingerprinting assay described here is a good practice that ensures that biobanking collections provide scientists with high quality, donor-verified biomaterial.
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Bancos de Muestras Biológicas , Recolección de Muestras de Sangre/instrumentación , Dermatoglifia del ADN/métodos , ADN/aislamiento & purificación , Donantes de Sangre , Recolección de Muestras de Sangre/métodos , ADN/sangre , Humanos , Repeticiones de Microsatélite , Reacción en Cadena de la Polimerasa MultiplexRESUMEN
When a biological specimen is donated to a biobank such as the nonprofit Coriell Institute for Medical Research, regardless of whether that submission is sent directly or through a physician, scientist, foundation, or patient-centered advocacy organization, the donor expects their biomaterial to be processed effectively and stored in proper conditions until distribution to researchers answering scientific questions. The donor and scientific researchers rarely, if ever, consider what might happen to those specimens if the biobank experiences an adverse event, such as a disaster that compromises its business operations, including handling of samples. Management of biomaterials is not simply a laboratory process; their long-term survival is dependent on both the laboratory preparation and the infrastructure designed for maintenance, safety, and security. Coriell Institute has documented disaster preparedness plans since its inception in 1953, and currently manages hundreds of thousands of cell lines and DNA samples under ISO 9001 quality management standards, complete with a robust Emergency Operations Plan. The Institute's recent approach to preparing for Hurricane Sandy, a Category 1 hurricane that struck the East Coast of the United States in late October 2012, was two-fold. It included the validation of its long-term strategies focused on emergency back-up systems, communication solutions, and employee training, and implementation of short-term tactics such as confirming on-call emergency response personnel and safe storage options for working biomaterials and reagents. The purpose of this article is to review several best practices in use at Coriell Institute associated with disaster planning and to identify and evaluate the effectiveness of those elements in coping with Hurricane Sandy.
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Bancos de Muestras Biológicas/organización & administración , Planificación en Desastres/métodos , Planificación en Desastres/tendencias , Tormentas Ciclónicas , Humanos , Guías de Práctica Clínica como Asunto , Estados UnidosRESUMEN
OBJECTIVE: We sought to develop a list of 5 tests, treatments, or services commonly used in rheumatology practice whose necessity or value should be questioned and discussed by physicians and patients. METHODS: We used a multistage process combining consensus methodology and literature reviews to arrive at the American College of Rheumatology's (ACR) Top 5 list. Rheumatologists from diverse practice settings generated items using the Delphi method. Items with high content agreement and perceived high prevalence advanced to a survey of ACR members, who comprise >90% of the US rheumatology workforce. To increase the response rate, a nested random sample of 390 rheumatologists received more intensive survey followup. The samples were combined and weighting procedures were applied to ensure generalizability. Items with high ratings underwent literature review. Final items were then selected and formulated by the task force. RESULTS: One hundred five unique items were proposed and narrowed down to 22 items during the Delphi rounds. A total of 1,052 rheumatologists (17% of those contacted) participated in the member-wide survey, whereas 33% of those in the nested random sample participated; respondent characteristics were similar in both samples. Based on survey results and available scientific evidence, 5 items (relating to antinuclear antibodies, Lyme disease, magnetic resonance imaging, bone absorptiometry, and biologic therapy for rheumatoid arthritis) were selected for inclusion. CONCLUSION: The ACR Top 5 list is intended to promote discussions between physicians and patients about health care practices in rheumatology whose use should be questioned and to assist rheumatologists in providing high-value care.
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Artritis Reumatoide/diagnóstico , Artritis Reumatoide/terapia , Conducta de Elección , Participación del Paciente , Médicos/normas , Reumatología/normas , Antirreumáticos/uso terapéutico , Productos Biológicos/uso terapéutico , Técnica Delphi , Pruebas Diagnósticas de Rutina/normas , Estudios de Seguimiento , Encuestas Epidemiológicas/métodos , Humanos , Enfermedad de Lyme/diagnóstico , Enfermedad de Lyme/terapia , Imagen por Resonancia Magnética/estadística & datos numéricos , Participación del Paciente/métodos , Guías de Práctica Clínica como Asunto/normas , Reumatología/métodos , Estados UnidosRESUMEN
OBJECTIVES: Grading of Recommendations Assessment, Development and Evaluation (GRADE) is a system for rating the confidence in estimates of effect and grading guideline recommendations. It promotes evaluation of the quality of the evidence for each outcome and an assessment of balance between desirable and undesirable outcomes leading to a judgment about the strength of the recommendation. In 2007, the National Institute for Health and Clinical Excellence began introducing GRADE across its clinical guideline program to enable separation of judgments about the evidence quality from judgments about the strength of the recommendation. STUDY DESIGN AND SETTING: We describe the process of implementing GRADE across guidelines. RESULTS: Use of GRADE has been positively received by both technical staff and guideline development group members. CONCLUSION: A shift in thinking about confidence in the evidence was required leading to a more structured and transparent approach to decision making. Practical problems were also encountered; these have largely been resolved, but some areas require further work, including the application of imprecision and presenting results from analyses considering more than two alternative interventions. The use of GRADE for nonrandomized and diagnostic accuracy studies needs to be refined.
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Epidemiología/normas , Práctica Clínica Basada en la Evidencia/organización & administración , Adhesión a Directriz/normas , Guías de Práctica Clínica como Asunto , Garantía de la Calidad de Atención de Salud/normas , Humanos , Desarrollo de Programa , Evaluación de Programas y Proyectos de Salud , Ensayos Clínicos Controlados Aleatorios como Asunto , Estados UnidosRESUMEN
Gout is an inflammatory arthritis characterized by sudden, painful inflammation. Gout can affect any joint in an asymmetric distribution. Gouty attacks may be isolated or can be followed by years of recurrent flares. Over time, elevated serum urate levels and tophaceous deposits can lead to deformity and disability from underlying bony erosion. The concept of 'treatment-failure gout' describes a unique population that has been either unable to tolerate allopurinol or who have not experienced normalization of serum urate levels on allopurinol. It is estimated that approximately 1-1.5% of the estimated 3-8 million people with gout in the USA have treatment-failure gout. Pegloticase is an US FDA-approved intravenous medication that is a mammalian recombinant uricase conjugated to monomethoxy polyethylene glycol. Two recent Phase III trials have found pegloticase to be effective in the management of treatment-failure gout. These studies also highlight safety concerns regarding the drug's immunogenicity.
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Enzimas Inmovilizadas/uso terapéutico , Supresores de la Gota/uso terapéutico , Gota/tratamiento farmacológico , Polietilenglicoles/uso terapéutico , Urato Oxidasa/uso terapéutico , Alopurinol/uso terapéutico , Femenino , Humanos , Infusiones Intravenosas , Masculino , Ensayos Clínicos Controlados Aleatorios como Asunto , Insuficiencia del Tratamiento , Resultado del Tratamiento , Ácido Úrico/sangreRESUMEN
Dax1, an atypical orphan nuclear receptor expressed in steroidogenic tissues, has recently been shown to be expressed in mouse embryonic stem (mES) cells and is required for pluripotency. While the mechanisms of transcriptional regulation of Dax1 in steroidogenic organs have been well characterized, those in mES cells have not. Here we report that 500 bp of the Dax1 gene promoter sequence are sufficient to drive expression in mES cells. In steroidogenic tissues, NR5A1 (Sf1) binds to nuclear receptor binding sites within this sequence to regulate Dax1 expression. In mES cells, while NR5A1 (Sf1) is not expressed, NR5A2 (LRH-1) expression is robust. Luciferase assays, EMSA and overexpression/knockdown studies demonstrate that LRH-1 binds the -128 site and regulates Dax1 in mES cells. Predicated on recent work indicating that Nanog binds to the Dax1 intron, we have used chromatin immunoprecipitation experiments (ChIP) to define an intronic site that is bound by Nanog. Overexpression and knockdown of Nanog in mES cells result in alteration of Dax1 expression, and luciferase assays reveal that this sequence can enhance transcription of a Dax1 reporter construct. These data indicate that LRH-1 and Nanog cooperate to regulate Dax1 expression in mES cells.