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1.
Nature ; 628(8008): 511-514, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38632480

RESUMEN

Beyond our Solar System, aurorae have been inferred from radio observations of isolated brown dwarfs1,2. Within our Solar System, giant planets have auroral emission with signatures across the electromagnetic spectrum including infrared emission of H3+ and methane. Isolated brown dwarfs with auroral signatures in the radio have been searched for corresponding infrared features, but only null detections have been reported3. CWISEP J193518.59-154620.3. (W1935 for short) is an isolated brown dwarf with a temperature of approximately 482 K. Here we report James Webb Space Telescope observations of strong methane emission from W1935 at 3.326 µm. Atmospheric modelling leads us to conclude that a temperature inversion of approximately 300 K centred at 1-10 mbar replicates the feature. This represents an atmospheric temperature inversion for a Jupiter-like atmosphere without irradiation from a host star. A plausible explanation for the strong inversion is heating by auroral processes, although other internal and external dynamical processes cannot be ruled out. The best-fitting model rules out the contribution of H3+ emission, which is prominent in Solar System gas giants. However, this is consistent with rapid destruction of H3+ at the higher pressure where the W1935 emission originates4.

2.
Brain ; 142(2): 334-343, 2019 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-30535170

RESUMEN

Males with adrenoleukodystrophy develop progressive myelopathy causing severe disability later in life. No treatment is currently available, but new disease-modifying therapies are under development. Knowledge of the natural history of the myelopathy is of paramount importance for evaluation of these therapies in clinical trials, but prospective data on disease progression are lacking. We performed a prospective observational cohort study to quantify disease progression over 2 years of follow-up. Signs and symptoms, functional outcome measures and patient-reported outcomes were assessed at baseline, 1 and 2 years of follow-up. We included 46 male adrenoleukodystrophy patients (median age 45.5 years, range 16-71). Frequency of myelopathy at baseline increased with age from 30.8% (<30 years) to 94.7% (>50 years). Disease progression was measured in the patients who were symptomatic at baseline (n = 24) or became symptomatic during follow-up (n = 1). Significant progression was detected with the functional outcome measures and quantitative vibration measurements. Over 2 years of follow-up, Expanded Disability Status Score increased by 0.34 points (P = 0.034), Severity Scoring system for Progressive Myelopathy decreased by 2.78 points (P = 0.013), timed up-and-go increased by 0.82 s (P = 0.032) and quantitative vibration measurement at the hallux decreased by 0.57 points (P = 0.040). Changes over 1-year follow-up were not significant, except for the 6-minute walk test that decreased by 19.67 meters over 1 year (P = 0.019). None of the patient-reported outcomes were able to detect disease progression. Our data show that progression of myelopathy in adrenoleukodystrophy can be quantified using practical and clinically relevant outcome measures. These results will help in the design of clinical trials and the development of new biomarkers for the myelopathy of adrenoleukodystrophy.10.1093/brain/awy299_video1awy299media15995811923001.


Asunto(s)
Adrenoleucodistrofia/diagnóstico por imagen , Adrenoleucodistrofia/fisiopatología , Progresión de la Enfermedad , Enfermedades de la Médula Espinal/diagnóstico por imagen , Enfermedades de la Médula Espinal/fisiopatología , Adolescente , Adrenoleucodistrofia/epidemiología , Adulto , Anciano , Estudios de Cohortes , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Enfermedades de la Médula Espinal/epidemiología , Adulto Joven
3.
Clin Infect Dis ; 65(6): 1026-1032, 2017 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-28520858

RESUMEN

Rapid diagnosis of respiratory virus infections contributes to patient care. This systematic review evaluates the diagnostic accuracy of rapid tests for the detection of respiratory viruses. We searched Medline and EMBASE for studies evaluating these tests against polymerase chain reaction as the reference standard. Of 179 studies included, 134 evaluated rapid tests for influenza viruses, 32 for respiratory syncytial virus (RSV), and 13 for other respiratory viruses. We used the bivariate random effects model for quantitative meta-analysis of the results. Most tests detected only influenza viruses or RSV. Summary sensitivity and specificity estimates of tests for influenza were 61.1% and 98.9%. For RSV, summary sensitivity was 75.3%, and specificity, 98.7%. We assessed the quality of studies using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) checklist. Because of incomplete reporting, the risk of bias was often unclear. Despite their intended use at the point of care, 26.3% of tests were evaluated in a laboratory setting. Although newly developed tests seem more sensitive, high-quality evaluations of these tests are lacking.


Asunto(s)
Diagnóstico Precoz , Gripe Humana/diagnóstico , Pruebas en el Punto de Atención , Infecciones por Virus Sincitial Respiratorio/diagnóstico , Técnicas de Diagnóstico del Sistema Respiratorio , Humanos , Reacción en Cadena de la Polimerasa , Enfermedades Respiratorias/diagnóstico , Enfermedades Respiratorias/virología , Sensibilidad y Especificidad , Factores de Tiempo
4.
Blood ; 113(10): 2312-23, 2009 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-19074734

RESUMEN

CD8(+) T cells recognizing minor histocompatibility antigens (MiHAs) on leukemic stem and progenitor cells play a pivotal role in effective graft-versus-leukemia reactivity after allogeneic stem cell transplantation (SCT). Previously, we identified a hematopoiesis-restricted MiHA, designated LRH-1, which is presented by HLA-B7 and encoded by the P2X5 purinergic receptor gene. We found that P2X5 is significantly expressed in CD34(+) leukemic subpopulations from chronic myeloid leukemia (CML) and acute myeloid leukemia (AML) patients. Here, we demonstrate that LRH-1-specific CD8(+) T-cell responses are frequently induced in myeloid leukemia patients following donor lymphocyte infusions. Patients with high percentages of circulating LRH-1-specific CD8(+) T cells had no or only mild graft-versus-host disease. Functional analysis showed that LRH-1-specific cytotoxic T lymphocytes (CTLs) isolated from 2 different patients efficiently target LRH-1-positive leukemic CD34(+) progenitor cells from both CML and AML patients, whereas mature CML cells are only marginally lysed due to down-regulation of P2X5. Furthermore, we observed that relative resistance to LRH-1 CTL-mediated cell death due to elevated levels of antiapoptotic XIAP could be overcome by IFN-gamma prestimulation and increased CTL-target ratios. These findings provide a rationale for use of LRH-1 as immunotherapeutic target antigen to treat residual or persisting myeloid malignancies after allogeneic SCT.


Asunto(s)
Proteínas de Unión al ADN/inmunología , Leucemia Mieloide/inmunología , Células Madre Neoplásicas/inmunología , Linfocitos T Citotóxicos/inmunología , Factores de Transcripción/inmunología , Adulto , Antígenos CD34/inmunología , Antígenos CD34/metabolismo , Femenino , Citometría de Flujo , Expresión Génica , Enfermedad Injerto contra Huésped/inmunología , Trasplante de Células Madre Hematopoyéticas , Humanos , Leucemia Mieloide/genética , Masculino , Persona de Mediana Edad , ARN Mensajero/análisis , Receptores Purinérgicos P2/genética , Receptores Purinérgicos P2X5 , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Proteína Inhibidora de la Apoptosis Ligada a X/biosíntesis , Proteína Inhibidora de la Apoptosis Ligada a X/genética
5.
Science ; 368(6487): 169-172, 2020 04 10.
Artículo en Inglés | MEDLINE | ID: mdl-32273464

RESUMEN

Zonal (latitudinal) winds dominate the bulk flow of planetary atmospheres. For gas giant planets such as Jupiter, the motion of clouds can be compared with radio emissions from the magnetosphere, which is connected to the planet's interior, to determine the wind speed. In principle, this technique can be applied to brown dwarfs and/or directly imaged exoplanets if periods can be determined for both the infrared and radio emissions. We apply this method to measure the wind speeds on the brown dwarf 2MASS J10475385+2124234. The difference between the radio period of 1.751 to 1.765 hours and infrared period of 1.741 ± 0.007 hours implies a strong wind (+650 ± 310 meters per second) proceeding eastward. This could be due to atmospheric jet streams and/or low frictional drag at the bottom of the atmosphere.

6.
Cancer Immunol Immunother ; 58(3): 429-39, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18719914

RESUMEN

CD8(+) T cells recognizing minor histocompatibility antigens (MiHA) on solid tumor cells may mediate effective graft-versus-tumor (GVT) reactivity after allogeneic stem cell transplantation (SCT). Previously, we identified LRH-1 as a hematopoietic-restricted MiHA encoded by the P2X5 gene. Here, we report that LRH-1 is aberrantly expressed on solid tumor cells. P2X5 mRNA expression is demonstrated in a significant portion of solid tumor cell lines, including renal cell carcinoma (RCC), melanoma, colorectal carcinoma, brain cancer and breast cancer. Importantly, P2X5 gene expression was also detected in a subset of primary solid tumor specimens derived from RCC, brain cancer and breast cancer patients. Furthermore, P2X5 expressing solid tumor cells can be effectively targeted by LRH-1-specific cytotoxic T lymphocytes under inflammatory conditions. The expression of HLA-B7 and CD54 on tumor cells increases upon cytokine stimulation resulting in improved T cell activation as observed by higher levels of degranulation and enhanced tumor cell lysis. Overall, hematopoietic-restricted MiHA LRH-1 is aberrantly expressed on solid tumor cells and may be used as target in GVT-specific immunotherapy after SCT.


Asunto(s)
Proteínas de Unión al ADN/metabolismo , Sistema Hematopoyético/metabolismo , Antígenos de Histocompatibilidad Menor/metabolismo , Neoplasias/inmunología , Receptores Purinérgicos P2/metabolismo , Linfocitos T/metabolismo , Factores de Transcripción/metabolismo , Linfocitos T CD8-positivos/inmunología , Proteínas de Unión al ADN/fisiología , Genotipo , Humanos , Inmunoterapia/métodos , Molécula 1 de Adhesión Intercelular/biosíntesis , Microscopía Fluorescente/métodos , Neoplasias/metabolismo , ARN Mensajero/metabolismo , Receptores Purinérgicos P2X5 , Trasplante de Células Madre , Factores de Transcripción/fisiología , Trasplante Homólogo
7.
Neurology ; 93(23): e2133-e2143, 2019 12 03.
Artículo en Inglés | MEDLINE | ID: mdl-31719133

RESUMEN

OBJECTIVE: To prospectively determine the potential of diffusion MRI (dMRI) of the cervical spinal cord and the corticospinal tracts in brain as surrogate outcome measure for progression of myelopathy in men with adrenoleukodystrophy, as better outcome measures to quantify progression of myelopathy would enable clinical trials with fewer patients and shorter follow-up. METHODS: Clinical assessment of myelopathy included Expanded Disability Status Scale (EDSS), Severity Scoring System for Progressive Myelopathy (SSPROM), Timed Up-and-Go, and 6-Minute Walk Test. Applied dMRI metrics included fractional anisotropy, mean diffusivity, axial diffusivity, and radial diffusivity. RESULTS: Data were available for 33 controls and 52 patients. First, cross-sectionally, differences between groups (controls vs patients; controls vs asymptomatic patients vs symptomatic patients) were statistically significant for fractional anisotropy, mean diffusivity, and radial diffusivity in spinal cord and brain corticospinal tracts (effect size 0.31-0.68). Correlations between dMRI metrics and clinical measures were moderate to strong (correlation coefficient 0.35-0.60). Second, longitudinally (n = 36), change on clinical measures was significant after 2-year follow-up for EDSS, SSPROM, and Timed Up-and-Go (p ≤ 0.021, effect size ≤0.14). Change on brain fractional anisotropy and radial diffusivity was slightly larger (p ≤ 0.002, effect sizes 0.16-0.28). In addition, a statistically significant change was detectable in asymptomatic patients using brain dMRI and not using the clinical measures. Change on clinical measures did not correlate to change on dMRI metrics. CONCLUSION: Although effect sizes were small, our prospective data illustrate the potential of dMRI as surrogate outcome measure for progression of myelopathy in men with adrenoleukodystrophy.


Asunto(s)
Adrenoleucodistrofia/diagnóstico por imagen , Adrenoleucodistrofia/patología , Neuroimagen/métodos , Enfermedades de la Médula Espinal/diagnóstico por imagen , Enfermedades de la Médula Espinal/patología , Adolescente , Adrenoleucodistrofia/complicaciones , Adulto , Anciano , Imagen de Difusión por Resonancia Magnética/métodos , Progresión de la Enfermedad , Humanos , Interpretación de Imagen Asistida por Computador/métodos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Tractos Piramidales/diagnóstico por imagen , Tractos Piramidales/patología , Enfermedades de la Médula Espinal/etiología , Adulto Joven
8.
Target Oncol ; 10(3): 439-43, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25529578

RESUMEN

Concerns have been raised about the development of heart failure in patients treated for cancer with angiogenesis inhibitors, such as the tyrosine kinase inhibitor sunitinib. Patients with previous coronary artery disease and hypertension have an increased risk of developing heart failure. Therefore, we studied the effect of sunitinib on the contractility of isolated human atrial trabeculae and the effect on recovery after ischemic stimulation. After informed consent, the atrial appendage of patients undergoing cardiac surgery was harvested and isolated trabeculae were placed in an organ bath with a force transducer. During electrical stimulation, contractile force was measured during normal pacing or after simulated ischemia. Of each patient, one trabecula was perfused with control and one with sunitinib. Contractile force (expressed as percentage of baseline force) declined over time to 57 ± 8 and 73 ± 20% after 150 min of stimulation for solvent- and sunitinib-treated trabeculae, respectively (mean ± SE; n = 8; p > 0.1). After simulated ischemia and reperfusion, contractile force was 40 ± 6% in the control compared to 39 ± 6% in the sunitinib-treated trabeculae during the last final 5 min of reperfusion (n = 12; p > 0.1). Sunitinib at low, but clinically relevant, concentrations does not have a direct effect on function of human atrial cardiomyocytes nor does it attenuate the recovery in contractile force of atrial cardiomyocytes after a period of ischemia. A direct and acute toxic effect on cardiomyocytes does not explain the development of heart failure in patients treated with sunitinib.


Asunto(s)
Atrios Cardíacos/efectos de los fármacos , Indoles/uso terapéutico , Isquemia/tratamiento farmacológico , Contracción Miocárdica/efectos de los fármacos , Miocardio/patología , Pirroles/uso terapéutico , Adulto , Anciano , Puente de Arteria Coronaria , Estimulación Eléctrica , Femenino , Insuficiencia Cardíaca/inducido químicamente , Insuficiencia Cardíaca/fisiopatología , Humanos , Indoles/efectos adversos , Masculino , Persona de Mediana Edad , Pirroles/efectos adversos , Daño por Reperfusión , Solventes/química , Sunitinib , Factor A de Crecimiento Endotelial Vascular/metabolismo
9.
PLoS One ; 6(6): e21699, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21738768

RESUMEN

Nonmyeloablative allogeneic stem cell transplantation (SCT) can induce remission in patients with renal cell carcinoma (RCC), but this graft-versus-tumor (GVT) effect is often accompanied by graft-versus-host disease (GVHD). Here, we evaluated minor histocompatibility antigen (MiHA)-specific T cell responses in two patients with metastatic RCC who were treated with reduced-intensity conditioning SCT followed by donor lymphocyte infusion (DLI). One patient had stable disease and emergence of SMCY.A2-specific CD8+ T cells was observed after DLI with the potential of targeting SMCY-expressing RCC tumor cells. The second patient experienced partial regression of lung metastases from whom we isolated a MiHA-specific CTL clone with the capability of targeting RCC cell lines. Whole genome association scanning revealed that this CTL recognizes a novel HLA-B7-restricted MiHA, designated ZAPHIR, resulting from a polymorphism in the splice donor site of the ZNF419 gene. Tetramer analysis showed that emergence of ZAPHIR-specific CD8+ T cells in peripheral blood occurred in the absence of GVHD. Furthermore, the expression of ZAPHIR in solid tumor cell lines indicates the involvement of ZAPHIR-specific CD8+ T cell responses in selective GVT immunity. These findings illustrate that the ZNF419-encoded MiHA ZAPHIR is an attractive target for specific immunotherapy after allogeneic SCT.


Asunto(s)
Carcinoma de Células Renales/genética , Antígenos de Histocompatibilidad Menor/genética , Polimorfismo Genético/genética , Sitios de Empalme de ARN/genética , Carcinoma de Células Renales/terapia , Células Cultivadas , Citometría de Flujo , Humanos , Masculino , Trasplante de Células Madre , Trasplante Homólogo
10.
J Immunol ; 178(3): 1405-14, 2007 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-17237388

RESUMEN

Signaling by the BCR involves activation of several members of the Ras superfamily of small GTPases, among which is Ras itself. Ras can control the activity of multiple effectors, including Raf, PI3K, and guanine nucleotide exchange factors for the small GTPase Ral. Ras, Raf, and PI3K have been implicated in a variety of processes underlying B cell development, differentiation, and function; however, the role of Ral in B lymphocytes remains to be established. In this study, we show that Ral is activated upon BCR stimulation in human tonsillar and mouse splenic B lymphocytes and in B cell lines. Using signaling molecule-deficient B cells, we demonstrate that this activation is mediated by Lyn and Syk, Btk, phospholipase C-gamma2, and inositol-1,4,5-trisphosphate receptor-mediated Ca(2+) release. In addition, although Ral can be activated by Ras-independent mechanisms, we demonstrate that BCR-controlled activation of Ral is dependent on Ras. By means of expression of the dominant-negative mutants RasN17 and RalN28, or of RalBPDeltaGAP, a Ral effector mutant which sequesters active Ral, we show that Ras and Ral mediate BCR-controlled transcription of c-fos. Furthermore, while not involved in NF-kappaB activation, Ras and Ral mediate BCR-controlled activation of JUN/ATF2 and NFAT transcription factors. Taken together, our data show that Ral is activated upon BCR stimulation and mediates BCR-controlled activation of AP-1 and NFAT transcription factors. These findings suggest that Ral plays an important role in B cell development and function.


Asunto(s)
Factores de Transcripción NFATC/metabolismo , Receptores de Antígenos de Linfocitos B/fisiología , Factor de Transcripción AP-1/metabolismo , Proteínas de Unión al GTP ral/metabolismo , Proteínas ras/metabolismo , Linfocitos B/citología , Linfocitos B/fisiología , Línea Celular Tumoral , Células Cultivadas , Humanos , Mutación , Tonsila Palatina/citología , Proteínas de Unión al GTP ral/genética
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