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1.
Phys Rev Lett ; 132(13): 131001, 2024 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-38613296

RESUMEN

We searched for antideuterons (d[over ¯]'s) in the 4.7×10^{9} cosmic-ray events observed during the BESS-Polar II flight at solar minimum in 2007-2008 but found no candidates. The resulting 95% C.L. upper limit on the d[over ¯] flux is 6.7×10^{-5} (m^{2} s sr GeV/n)^{-1} in an energy range from 0.163 to 1.100 GeV/n. The result has improved by more than a factor of 14 from the upper limit of BESS97, which had a potential comparable to that of BESS-Polar II in the search for cosmic-origin d[over ¯]'s and was conducted during the former solar minimum. The upper limit of d[over ¯] flux from BESS-Polar II is the first result achieving the sensitivity to constrain the latest theoretical predictions.

2.
Nature ; 456(7220): 362-5, 2008 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-19020615

RESUMEN

Galactic cosmic rays consist of protons, electrons and ions, most of which are believed to be accelerated to relativistic speeds in supernova remnants. All components of the cosmic rays show an intensity that decreases as a power law with increasing energy (for example as E(-2.7)). Electrons in particular lose energy rapidly through synchrotron and inverse Compton processes, resulting in a relatively short lifetime (about 10(5) years) and a rapidly falling intensity, which raises the possibility of seeing the contribution from individual nearby sources (less than one kiloparsec away). Here we report an excess of galactic cosmic-ray electrons at energies of approximately 300-800 GeV, which indicates a nearby source of energetic electrons. Such a source could be an unseen astrophysical object (such as a pulsar or micro-quasar) that accelerates electrons to those energies, or the electrons could arise from the annihilation of dark matter particles (such as a Kaluza-Klein particle with a mass of about 620 GeV).

3.
J Obstet Gynaecol ; 34(2): 153-5, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24456436

RESUMEN

Cervical length was measured at 34-36 weeks' gestation by transvaginal ultrasound. The purpose of measurement of cervical length before term was to reveal the association with the onset of term labour. This was a retrospective study of 362 women who were delivered at term at Mizmedi hospital, between August 2006 and November 2011. There was significant linear correlation between cervical length and the scan-to-labour interval in women with labour before 41 weeks. The measurement of cervical length at 34-36 weeks' gestation might be helpful in predicting the onset of term labour before 41 weeks.


Asunto(s)
Medición de Longitud Cervical , Inicio del Trabajo de Parto , Nacimiento a Término , Adulto , Femenino , Humanos , Valor Predictivo de las Pruebas , Embarazo , Estudios Retrospectivos
4.
Br J Surg ; 100(5): 668-73, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23334982

RESUMEN

BACKGROUND: Endoscopic submucosal dissection (ESD) is not considered appropriate for all submucosal cancers owing to the risk of lymph node metastasis and difficulty estimating the deep margin status. This study aimed to determine predictive factors for lymph node metastases in submucosal cancer and to explore in which patients ESD might be feasible. METHODS: Details of patients who had curative gastrectomy for submucosal gastric cancer at Asan Medical Centre from 2007 to 2011 were reviewed retrospectively to determine the relationship between lymph node metastasis and clinicopathological characteristics, including age, sex, tumour location, size, gross appearance, depth of invasion, histological type/differentiation, presence of lymphovascular/perineural invasion, and immunohistochemical staining results for p53, human epidermal growth factor receptor (HER) 1 and HER2. RESULTS: A total of 1773 patients were analysed. The presence of lymphovascular invasion was related most strongly to lymph node metastasis. Multivariable analysis revealed that depth of invasion, tumour size, differentiation, gross appearance and perineural invasion were also related. Metastatic lymph nodes were found in four of 105 patients who met the classical criteria for ESD; all showed a moderately differentiated histological appearance. No lymph node metastases were observed in well differentiated SM1 tumours of any size (infiltration into upper third of submucosa), or in well differentiated SM2 (infiltration into middle third of submucosa) tumours of 2 cm or less without lymphovascular invasion. CONCLUSION: Patients with well differentiated SM1 cancer of any size and those with well differentiated SM2 cancer of 2 cm or less without lymphovascular invasion may be suitable candidates for ESD.


Asunto(s)
Gastrectomía/métodos , Mucosa Gástrica/cirugía , Gastroscopía/métodos , Neoplasias Gástricas/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Algoritmos , Disección/métodos , Estudios de Factibilidad , Femenino , Mucosa Gástrica/patología , Humanos , Metástasis Linfática , Masculino , Persona de Mediana Edad , Análisis Multivariante , Invasividad Neoplásica/patología , Estudios Retrospectivos , Neoplasias Gástricas/patología
5.
Phys Rev Lett ; 108(5): 051102, 2012 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-22400920

RESUMEN

The energy spectrum of cosmic-ray antiprotons (p's) from 0.17 to 3.5 GeV has been measured using 7886 p's detected by BESS-Polar II during a long-duration flight over Antarctica near solar minimum in December 2007 and January 2008. This shows good consistency with secondary p calculations. Cosmologically primary p's have been investigated by comparing measured and calculated p spectra. BESS-Polar II data show no evidence of primary p's from the evaporation of primordial black holes.

6.
Phys Rev Lett ; 108(13): 131301, 2012 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-22540691

RESUMEN

In two long-duration balloon flights over Antarctica, the Balloon-borne Experiment with a Superconducting Spectrometer (BESS) collaboration has searched for antihelium in the cosmic radiation with the highest sensitivity reported. BESS-Polar I flew in 2004, observing for 8.5 days. BESS-Polar II flew in 2007-2008, observing for 24.5 days. No antihelium candidate was found in BESS-Polar I data among 8.4×10(6) |Z|=2 nuclei from 1.0 to 20 GV or in BESS-Polar II data among 4.0×10(7) |Z|=2 nuclei from 1.0 to 14 GV. Assuming antihelium to have the same spectral shape as helium, a 95% confidence upper limit to the possible abundance of antihelium relative to helium of 6.9×10(-8)} was determined combining all BESS data, including the two BESS-Polar flights. With no assumed antihelium spectrum and a weighted average of the lowest antihelium efficiencies for each flight, an upper limit of 1.0×10(-7) from 1.6 to 14 GV was determined for the combined BESS-Polar data. Under both antihelium spectral assumptions, these are the lowest limits obtained to date.

7.
Int J Sports Med ; 33(1): 76-80, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22134884

RESUMEN

Mitochondrial DNA (mtDNA) variation has recently been suggested to have an association with athletic performance or physical endurance. Since mtDNA is haploid and lacks recombination, specific mutations in the mtDNA genome associated with human exercise tolerance or intolerance arise and remain in particular genetic backgrounds referred to as haplogroups. To assess the possible contribution of mtDNA haplogroup-specific variants to differences in elite athletic performance, we performed a population-based study of 152 Korean elite athletes [77 sprint/power athletes (SPA) and 75 endurance/middle-power athletes (EMA)] and 265 non-athletic controls (CON). The overall haplogroup distribution of EMA differed significantly from CON (p<0.01), but that of SPA did not. The EMA have an excess of haplogroups M* (OR 4.38, 95% CI 1.63-11.79, p=0.003) and N9 (OR 2.32, 95% CI 0.92-5.81, p=0.042), but a dearth of haplogroup B (OR 0.26, 95% CI 0.09-0.75, p=0.003) compared with the CON. Thus, our data imply that specific mtDNA lineages may provide a significant effect on elite Korean endurance status, although functional studies with larger sample sizes are necessary to further substantiate these findings.


Asunto(s)
Atletas , Rendimiento Atlético/fisiología , ADN Mitocondrial/genética , Resistencia Física/genética , Adolescente , Adulto , Pueblo Asiatico , Femenino , Haplotipos , Humanos , Masculino , República de Corea , Adulto Joven
8.
J Air Waste Manag Assoc ; 61(11): 1174-82, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22168101

RESUMEN

In order to better understand the characteristics of atmospheric carbonaceous aerosol at a background site in Northeast Asia, semicontinuous organic carbon (OC) and elemental carbon (EC), and time-resolved water-soluble organic carbon (WSOC) were measured by a Sunset OC/ EC and a PILS-TOC (particle-into-liquid sampler coupled with an online total organic carbon) analyzer, respectively, at the Gosan supersite on Jeju Island, Korea, in the summer (May 28-June 17) and fall (August 24-September 30) of 2009. Hourly average OC concentration varied in the range of approximately 0.87-28.38 microgC m-3, with a mean of 4.07+/- 2.60 microgC m-3, while the hourly average EC concentration ranged approximately from 0.04 to 8.19 .microgC m-3, with a mean of 1.35 +/- 0.71 microgC m-3, from May 28 to June 17, 2009. During the fall season, OC varied in the approximate range 0.9-9.6 microgC m-3, with a mean of 2.30 +/-0.80 microgC m-3, whereas EC ranged approximately from 0.01 to 5.40 microgC m-3, with a mean of 0.66 +/- 0.38 microgC m-3. Average contributions of EC to TC and WSOC to OC were 26.0% +/- 9.7% and 20.6% +/-7.4%, and 37.6% +/- 23.5% and 57.2% +/- 22.2% during summer and fall seasons, respectively. As expected, clear diurnal variation of WSOC/OC was found in summer, varying from 0.22 during the nighttime up to 0.72 during the daytime, mainly due to the photo-oxidation process. In order to investigate the effect of air mass pathway on the characteristics of carbonaceous aerosol, 5-day back-trajectory analysis was conducted using the HYSPLIT model. The air mass pathways were classified into four types: Continental (CC), Marine (M), East Sea (ES) and Korean Peninsula (KP). The highest OC/EC ratio of 3.63 was observed when air mass originated from the Continental area (CC). The lowest OC/EC ratio of 0.79 was measured when air mass originated from the Marine area (M). A high OC concentration was occasionally observed at Gosan due to local biomass burning activities. The contribution of secondary OC to total OC varied approximately between 8.4% and 32.2% and depended on air mass type.


Asunto(s)
Aerosoles/química , Contaminantes Atmosféricos/química , Carbono/química , Tamaño de la Partícula , Material Particulado/química , Ritmo Circadiano , Monitoreo del Ambiente , República de Corea , Factores de Tiempo
9.
Biochemistry ; 48(13): 2849-57, 2009 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-19290668

RESUMEN

Aberrant chromosomal fusion of the Ewings sarcoma oncogene (EWS) to several different cellular partners gives rise to the Ewing's family of oncogenic proteins [EWS fusion proteins (EFPs)] and associated tumors (EFTs). EFPs are potent transcriptional activators dependent on the N-terminal region of EWS [the EWS activation domain (EAD)], and this function is thought to be central to EFT oncogenesis and maintenance. Thus, EFPs are promising therapeutic targets, and detailed molecular studies of the EAD will be pivotal for exploring this potential. For many reasons, the molecular mechanism of EAD action is poorly understood and one major obstacle to progress is the lack of an in vitro transcription assay. Using well-characterized EAD-dependent activators and soluble nuclear extracts, we have attempted to recapitulate EAD transcriptional activity in vitro. We report that while the EAD activates transcription strongly in vitro, the effect of EAD mutations is strikingly different from that observed in vivo. Our results therefore suggest that crude soluble extracts do not support bona fide EAD activity in vitro, and we discuss our findings in relation to future assay development and potential mechanisms of EAD action.


Asunto(s)
Proteína EWS de Unión a ARN/química , Proteína EWS de Unión a ARN/metabolismo , Activación Transcripcional , Bacterias , Bioensayo , ADN/metabolismo , Células HeLa , Humanos , Proteínas Mutantes/aislamiento & purificación , Proteínas Mutantes/metabolismo , Unión Proteica , Estructura Terciaria de Proteína , Relación Estructura-Actividad
10.
J Cell Biol ; 103(4): 1405-14, 1986 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-3771643

RESUMEN

A monoclonal antibody has been developed against the putative junctional protein or spanning protein (SP) from skeletal muscle triads. By immuno-affinity chromatography, we have purified this protein. The native protein has a molecular mass of 630-800 kD, as determined by gel filtration and rate zonal centrifugation. Within the limits of the methods used, the basic unit of the SP appears to be a dimer. In electron micrographs, it is shown to exhibit a circular profile with a diameter of approximately 100 A. In thin section analysis, the protein is frequently observed as parallel tracks of electron-dense particles bordering a translucent core. We suggest that the basic unit of the junctional structure is a dimer of 300-kD subunits and that four such entities constitute the intact SP. The purified protein has been used to develop polyclonal antibodies. By immunoelectron microscopy using immunogold probes, the SP has been localized to the junctional gap of the triad. By attaching the SP to an affinity resin, three proteins have been identified as forming associations with the SP. The Mrs of the proteins are 150, 62, and 38 kD; the 62-kD protein is calsequestrin.


Asunto(s)
Proteínas Musculares/aislamiento & purificación , Músculos/análisis , Animales , Anticuerpos Monoclonales/inmunología , Cromatografía de Afinidad , Cromatografía en Gel , Microscopía Electrónica , Proteínas Musculares/inmunología , Músculos/ultraestructura , Conejos
11.
Science ; 289(5476): 101-4, 2000 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-10884220

RESUMEN

A new superacid, H(CB11H6X6) (where X = chlorine or bromine), whose conjugate base is the exceptionally inert CB11H6X6- carborane anion, separates Bronsted acidity from oxidizing capacity and anion nucleophilicity in a manner not previously achieved. Reaction of this superacid with C60 gives HC60+ as a stable ion in solution and in the solid state. In a separate experiment, an oxidant was developed such that the long-sought C60.+ ion can be synthesized in solution. The preparation of these two fullerene carbocations is a notable departure from the prevalent chemistry of C60, which is dominated by the formation of anions or the addition of nucleophiles. The H(CB11H6X6) superacid overcomes the major limitations of presently known superacids and has potentially wide application.


Asunto(s)
Ácidos/química , Carbono/química , Fulerenos , Ácidos/síntesis química , Aniones/química , Cationes Monovalentes/química , Espectroscopía de Resonancia Magnética , Modelos Químicos , Estructura Molecular , Oxidantes , Oxidación-Reducción , Protones , Espectrofotometría Infrarroja , Análisis Espectral
12.
Protein Sci ; 27(3): 633-642, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29193371

RESUMEN

The FET sub-family (FUS/TLS, EWS, TAF15) of RNA-binding proteins have remarkably similar overall structure but diverse biological and pathological roles. The molecular basis for FET protein specialization is largely unknown. Gly-Arg-Rich regions (RGG-boxes) within FET proteins are targets for methylation by Protein-Arginine-Methyl-Transferase-1 (PRMT1) and substrate capture is thought to involve electrostatic attraction between positively charged polyRGG substrates and negatively charged surface channels of PRMT1. Unlike FUS and EWS, a high proportion of TAF15 RGG-boxes are embedded within neutrally charged YGGDR(S/G)G repeats, suggesting that they might not bind well to PRMT1. This notion runs contrary however to a report that YGGDR(S/G)G repeats are methylated by PRMT1. Using peptide-based polyRGG substrates and a novel 2-hybrid binding assay, we find that the Asp residue in YGGDR(S/G)G repeats confers poor binding to PRMT1. Our results therefore indicate that YGGDR(S/G)G repeats may contribute to TAF15 specialization by enabling differential interactions with PRMT1 and reduced overall levels of TAF15 methylation compared with other FET proteins. By analogy with molecular recognition of other disordered polyvalent ligands by globular protein partners, we also propose a dynamic polyelectrostatic model for substrate capture by PRMT1.


Asunto(s)
Proteína-Arginina N-Metiltransferasas/metabolismo , Proteína EWS de Unión a ARN/metabolismo , Proteínas Represoras/metabolismo , Factores Asociados con la Proteína de Unión a TATA/metabolismo , Asparagina/metabolismo , Sitios de Unión , Línea Celular , Humanos , Metilación , Unión Proteica , Dominios y Motivos de Interacción de Proteínas , Proteína EWS de Unión a ARN/química , Factores Asociados con la Proteína de Unión a TATA/química
13.
J Geophys Res Atmos ; 123(10): 5560-5587, 2018 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-32661496

RESUMEN

Analysis of sun photometer measured and satellite retrieved aerosol optical depth (AOD) data has shown that major aerosol pollution events with very high fine mode AOD (>1.0 in mid-visible) in the China/Korea/Japan region are often observed to be associated with significant cloud cover. This makes remote sensing of these events difficult even for high temporal resolution sun photometer measurements. Possible physical mechanisms for these events that have high AOD include a combination of aerosol humidification, cloud processing, and meteorological co-variation with atmospheric stability and convergence. The new development of Aerosol Robotic network (AERONET) Version 3 Level 2 AOD with improved cloud screening algorithms now allow for unprecedented ability to monitor these extreme fine mode pollution events. Further, the Spectral Deconvolution Algorithm (SDA) applied to Level 1 data (L1; no cloud screening) provides an even more comprehensive assessment of fine mode AOD than L2 in current and previous data versions. Studying the 2012 winter-summer period, comparisons of AERONET L1 SDA daily average fine mode AOD data showed that Moderate Resolution Imaging Spectroradiometer (MODIS) satellite remote sensing of AOD often did not retrieve and/or identify some of the highest fine mode AOD events in this region. Also, compared to models that include data assimilation of satellite retrieved AOD, the L1 SDA fine mode AOD was significantly higher in magnitude, particularly for the highest AOD events that were often associated with significant cloudiness.

14.
Bone Joint J ; 99-B(6): 741-748, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28566392

RESUMEN

AIMS: We conducted a prospective study of a delta ceramic total hip arthroplasty (THA) to determine the rate of ceramic fracture, to characterise post-operative noise, and to evaluate the mid-term results and survivorship. PATIENTS AND METHODS: Between March 2009 and March 2011, 274 patients (310 hips) underwent cementless THA using a delta ceramic femoral head and liner. At each follow-up, clinical and radiological outcomes were recorded. A Kaplan-Meier analysis was undertaken to estimate survival. RESULTS: Four patients (four hips) died and 18 patients (20 hips) were lost to follow-up within five years. The remaining 252 patients (286 hips) were followed for a mean of 66.5 months (60 to 84). There were 144 men (166 hips) and 108 women (120 hips) with a mean age of 49.7 years (16 to 83) at surgery. The mean pre-operative Harris Hip Score of 47.1 points improved to 93.8 points at final follow-up. Six patients reported squeaking in seven hips; however, none were audible. Radiolucent lines involving Gruen zones one and/or seven were seen in 52 hips (18.2%). No hip had detectable wear, focal osteolysis or signs of loosening. One hip was revised because of fracture of the ceramic liner, which occurred due to an undetected malseating of the ceramic liner at the time of surgery. One hip was revised for a periprosthetic fracture of the femur, and one hip was treated for periprosthetic joint infection. The six-year survivorship with re-operation for any reason as the endpoint was 99.0% (95% confidence interval 97.8% to 100%). DISCUSSION: The rate of delta ceramic fracture was 0.3% (one of 286). While ceramic head fracture was dominant in previous ceramic-on-ceramic THA, fracture of the delta ceramic liner due to malseating is a concern. Cite this article: Bone Joint J 2017;99-B:741-8.


Asunto(s)
Artroplastia de Reemplazo de Cadera/instrumentación , Cerámica , Prótesis de Cadera , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Artroplastia de Reemplazo de Cadera/efectos adversos , Artroplastia de Reemplazo de Cadera/métodos , Cerámica/efectos adversos , Femenino , Necrosis de la Cabeza Femoral/diagnóstico por imagen , Necrosis de la Cabeza Femoral/cirugía , Articulación de la Cadera/diagnóstico por imagen , Prótesis de Cadera/efectos adversos , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Ruido , Estudios Prospectivos , Diseño de Prótesis , Falla de Prótesis/etiología , Radiografía , Reoperación , Resultado del Tratamiento , Adulto Joven
15.
Cytogenet Genome Res ; 112(1-2): 170-5, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16276108

RESUMEN

We have studied a male patient with significant developmental delay, growth failure, hypotonia, girdle weakness, microcephaly, and multiple congenital anomalies including atrial (ASD) and ventricular (VSD) septal defects. Detailed cytogenetic and molecular analyses revealed three de novo X chromosome aberrations and a karyotype 46,Y,der(X)inv(X) (p11.4q11.2)inv(X)(q11.2q21.32 approximately q22.2)del(X)(q22.3q22.3) was determined. The three X chromosome aberrations in the patient include: a pericentric inversion (inv 1) that disrupted the Duchenne muscular dystrophy (DMD) gene, dystrophin, at Xp11.4; an Xq11.2q21.32 approximately q22.2 paracentric inversion (inv 2) putatively affecting no genes; and an interstitial deletion at Xq22.3 that results in functional nullisomy of several known genes, including a gene previously associated with X-linked nonsyndromic mental retardation, acyl-CoA synthetase long chain family member 4 (ACSL4). These findings suggest that the disruption of DMD and the absence of ACSL4 in the patient are responsible for neuromuscular disease and cognitive impairment.


Asunto(s)
Anomalías Múltiples/genética , Coenzima A Ligasas/genética , Discapacidades del Desarrollo/genética , Distrofina/genética , Discapacidad Intelectual/genética , Hipotonía Muscular/genética , Peso al Nacer , Niño , Aberraciones Cromosómicas , Cromosomas Humanos X , Femenino , Humanos , Recién Nacido , Masculino , Eliminación de Secuencia
16.
J Bone Joint Surg Br ; 88(10): 1390-2, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17012434

RESUMEN

In a 41-year-old man, right-sided infraspinatus muscle weakness was associated with compression of the suprascapular nerve caused by a spinoglenoid ganglion cyst. The lesion was confirmed using electromyography and MRI. In addition, arthroscopy showed an incomplete discoid labrum. The free inner edge of the labrum was removed as in a meniscectomy of a discoid meniscus in the knee joint. Arthroscopic decompression of the cyst was performed through a juxtaglenoid capsulotomy which was left open. Neurological function recovered completely.


Asunto(s)
Ganglión/patología , Síndromes de Compresión Nerviosa/patología , Escápula/anomalías , Articulación del Hombro/patología , Adulto , Artroscopía/métodos , Ganglión/complicaciones , Ganglión/cirugía , Humanos , Masculino , Síndromes de Compresión Nerviosa/complicaciones , Síndromes de Compresión Nerviosa/cirugía , Resultado del Tratamiento
17.
Beijing Da Xue Xue Bao Yi Xue Ban ; 38(1): 92-3, 2006 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-16415976

RESUMEN

We report an apparently benign familial 9p subtelomere deletion identified using chromosome-arm-specific subtelomere probes in a patient with multiple congenital anomalies. Our experience demonstrated that the discovery of a subtelomeric deletion and/or duplication does not always guarantee the identification of the etiology for the patients phenotype and a positive finding with subtelomere probes should always be followed by parental study with the same probe in order to distinguish a disease causing alteration from a benign familial polymorphism.


Asunto(s)
Deleción Cromosómica , Telómero/genética , Anomalías Congénitas/genética , Humanos , Recién Nacido , Recien Nacido Prematuro , Masculino , Eliminación de Secuencia
18.
Transcription ; 7(4): 141-51, 2016 08 07.
Artículo en Inglés | MEDLINE | ID: mdl-27159574

RESUMEN

The multi-functional TET (TAF15/EWS/TLS) or FET (FUS/EWS/TLS) protein family of higher organisms harbor a transcriptional-activation domain (EAD) and an RNA-binding domain (RBD). The transcriptional activation function is, however, only revealed in oncogenic TET-fusion proteins because in native TET proteins it is auto-repressed by RGG-boxes within the TET RBD. Auto-repression is suggested to involve direct cation-pi interactions between multiple Arg residues within RGG boxes and EAD aromatics. Via analysis of TET transcriptional activity in different organisms, we report herein that repression is not autonomous but instead requires additional trans-acting factors. This finding is not supportive of a proposed model whereby repression occurs via a simple intramolecular EAD/RGG-box interaction. We also show that RGG-boxes present within reiterated YGGDRGG repeats that are unique to TAF15, are defective for repression due to the conserved Asp residue. Thus, RGG boxes within TET proteins can be functionally distinguished. While our results show that YGGDRGG repeats are not involved in TAF15 auto-repression, their remarkable number and conservation strongly suggest that they may confer specialized properties to TAF15 and thus contribute to functional differentiation within the TET/FET protein family.


Asunto(s)
Secuencias de Aminoácidos , Dominios y Motivos de Interacción de Proteínas , Proteína EWS de Unión a ARN/metabolismo , Proteína FUS de Unión a ARN/metabolismo , Factores Asociados con la Proteína de Unión a TATA/metabolismo , Secuencia de Aminoácidos , Animales , Sitios de Unión , Línea Celular , Expresión Génica , Regulación de la Expresión Génica , Genes Reporteros , Unión Proteica , Proteína EWS de Unión a ARN/química , Proteína FUS de Unión a ARN/química , Factores Asociados con la Proteína de Unión a TATA/química , Transactivadores/metabolismo , Activación Transcripcional
19.
Astrophys J ; 822(2)2016 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-32713958

RESUMEN

The BESS-Polar Collaboration measured the energy spectra of cosmic-ray protons and helium during two long-duration balloon flights over Antarctica in December 2004 and December 2007, at substantially different levels of solar modulation. Proton and helium spectra probe the origin and propagation history of cosmic rays in the galaxy, and are essential to calculations of the expected spectra of cosmic-ray antiprotons, positrons, and electrons from interactions of primary cosmic-ray nuclei with the interstellar gas, and to calculations of atmospheric muons and neutrinos. We report absolute spectra at the top of the atmosphere for cosmic-ray protons in the kinetic energy range 0.2-160 GeV and helium nuclei 0.15-80 GeV/nucleon. The corresponding magnetic rigidity ranges are 0.6-160 GV for protons and 1.1-160 GV for helium. These spectra are compared to measurements from previous BESS flights and from ATIC-2, PAMELA, and AMS-02. We also report the ratio of the proton and helium fluxes from 1.1 GV to 160 GV and compare to ratios from PAMELA and AMS-02.

20.
Oncogene ; 20(46): 6689-99, 2001 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-11709703

RESUMEN

p73 is a nuclear protein that is similar in structure and function to p53. Notably, the C-terminal region of p73 has a regulatory function, through interactions with a positive or negative regulator. In this study, we use the yeast two-hybrid technique to identify a novel p73beta binding protein, designated amphiphysin IIb-1. Amphiphysin IIb-1 is one of the splicing variants of amphiphysin II, and has a shorter protein product than amphiphysin IIb, which has been previously reported. We confirmed that amphiphysin IIb-1 binds full-length p73beta, both in vitro and in vivo. This association is mediated via the SH3 domain of amphiphysin IIb-1 and C-terminal amino acids 321-376 of p73beta. Double immunofluorescence patterns revealed that p73beta is relocalized to the cytoplasm in the presence of amphiphysin IIb-1. Overexpression of amphiphysin IIb-1 was found to significantly inhibit the transcriptional activity of p73beta in a dose-dependent manner. In addition, the cell death function of p73beta was inhibited by amphiphysin IIb-1. These findings offer a new insight into the regulation mechanism of p73beta, and suggest that amphiphysin IIb-1 modulates p73beta function by direct binding.


Asunto(s)
Empalme Alternativo , Proteínas de Unión al ADN/metabolismo , Proteínas del Tejido Nervioso/química , Proteínas Nucleares/metabolismo , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Células COS , Muerte Celular , Citoplasma/metabolismo , Relación Dosis-Respuesta a Droga , Genes Supresores de Tumor , Luciferasas/metabolismo , Microscopía Fluorescente , Modelos Genéticos , Datos de Secuencia Molecular , Proteínas del Tejido Nervioso/genética , Plásmidos/metabolismo , Mutación Puntual , Unión Proteica , Estructura Terciaria de Proteína , Transcripción Genética , Proteína Tumoral p73 , Proteínas Supresoras de Tumor , Técnicas del Sistema de Dos Híbridos
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