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1.
Science ; 341(6150): 1080-2, 2013 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-24009386

RESUMO

The journey of the Sun through the dynamically active local interstellar medium creates an evolving heliosphere environment. This motion drives a wind of interstellar material through the heliosphere that has been measured with Earth-orbiting and interplanetary spacecraft for 40 years. Recent results obtained by NASA's Interstellar Boundary Explorer mission during 2009-2010 suggest that neutral interstellar atoms flow into the solar system from a different direction than found previously. These prior measurements represent data collected from Ulysses and other spacecraft during 1992-2002 and a variety of older measurements acquired during 1972-1978. Consideration of all data types and their published results and uncertainties, over the three epochs of observations, indicates that the trend for the interstellar flow ecliptic longitude to increase linearly with time is statistically significant.

2.
Science ; 336(6086): 1291-3, 2012 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-22582011

RESUMO

As the Sun moves through the local interstellar medium, its supersonic, ionized solar wind carves out a cavity called the heliosphere. Recent observations from the Interstellar Boundary Explorer (IBEX) spacecraft show that the relative motion of the Sun with respect to the interstellar medium is slower and in a somewhat different direction than previously thought. Here, we provide combined consensus values for this velocity vector and show that they have important implications for the global interstellar interaction. In particular, the velocity is almost certainly slower than the fast magnetosonic speed, with no bow shock forming ahead of the heliosphere, as was widely expected in the past.

3.
Science ; 326(5955): 966-8, 2009 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-19833915

RESUMO

Simulations of energetic neutral atom (ENA) maps predict flux magnitudes that are, in some cases, similar to those observed by the Interstellar Boundary Explorer (IBEX) spacecraft, but they miss the ribbon. Our model of the heliosphere indicates that the local interstellar medium (LISM) magnetic field (B(LISM)) is transverse to the line of sight (LOS) along the ribbon, suggesting that the ribbon may carry its imprint. The force-per-unit area on the heliopause from field line draping and the LISM ram pressure is comparable with the ribbon pressure if the LOS approximately 30 to 60 astronomical units and B(LISM) approximately 2.5 microgauss. Although various models have advantages in accounting for some of the observations, no model can explain all the dominant features, which probably requires a substantial change in our understanding of the processes that shape our heliosphere.

4.
Science ; 326(5955): 969-71, 2009 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-19833917

RESUMO

Neutral gas of the local interstellar medium flows through the inner solar system while being deflected by solar gravity and depleted by ionization. The dominating feature in the energetic neutral atom Interstellar Boundary Explorer (IBEX) all-sky maps at low energies is the hydrogen, helium, and oxygen interstellar gas flow. The He and O flow peaked around 8 February 2009 in accordance with gravitational deflection, whereas H dominated after 26 March 2009, consistent with approximate balance of gravitational attraction by solar radiation pressure. The flow distributions arrive from a few degrees above the ecliptic plane and show the same temperature for He and O. An asymmetric O distribution in ecliptic latitude points to a secondary component from the outer heliosheath.

5.
Science ; 326(5955): 959-62, 2009 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-19833923

RESUMO

The Sun moves through the local interstellar medium, continuously emitting ionized, supersonic solar wind plasma and carving out a cavity in interstellar space called the heliosphere. The recently launched Interstellar Boundary Explorer (IBEX) spacecraft has completed its first all-sky maps of the interstellar interaction at the edge of the heliosphere by imaging energetic neutral atoms (ENAs) emanating from this region. We found a bright ribbon of ENA emission, unpredicted by prior models or theories, that may be ordered by the local interstellar magnetic field interacting with the heliosphere. This ribbon is superposed on globally distributed flux variations ordered by both the solar wind structure and the direction of motion through the interstellar medium. Our results indicate that the external galactic environment strongly imprints the heliosphere.

6.
Br J Cancer ; 85(6): 875-80, 2001 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-11556840

RESUMO

There is disagreement concerning the expression of thyroid peroxidase (TPO) in thyroid cancer, some studies finding qualitative as well as quantitative differences compared to normal tissue. To investigate TPO protein expression and its antigenic properties, TPO was captured from a solubilizate of thyroid microsomes by a panel of murine anti-TPO monoclonal antibodies and detected with a panel of anti-human TPO IgGkappa Fab. TPO protein expression in 30 samples of malignant thyroid tissue was compared with TPO from adjacent normal tissues. Virtual absence of TPO expression was observed in 8 cases. In the remaining 22 malignant thyroid tumours the TPO protein level varied considerably from normal to nearly absent when compared to normal thyroid tissue or tissues from patients with Graves' disease (range less than 0.5 to more than 12.5 microg mg(-1) of protein). When expressed TPO displayed similar epitopes, to that of TPO from Graves' disease tissue. The results obtained by the TPO capturing method were confirmed by SDS-PAGE and Western blot analysis with both microsomes and their solubilizates. The present results show that in about two-thirds of differentiated thyroid carcinomas, TPO protein is expressed, albeit to a more variable extent than normal; when present, TPO in malignant tissues is immunologically normal.


Assuntos
Adenocarcinoma Folicular/enzimologia , Carcinoma Papilar/enzimologia , Doença de Graves/enzimologia , Iodeto Peroxidase/metabolismo , Doenças da Glândula Tireoide/enzimologia , Glândula Tireoide/enzimologia , Neoplasias da Glândula Tireoide/enzimologia , Adenocarcinoma Folicular/imunologia , Adolescente , Adulto , Idoso , Anticorpos Monoclonais , Western Blotting , Carcinoma Papilar/imunologia , Eletroforese em Gel de Poliacrilamida , Mapeamento de Epitopos , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Técnicas Imunoenzimáticas , Masculino , Microssomos/enzimologia , Microssomos/imunologia , Pessoa de Meia-Idade , Neoplasias da Glândula Tireoide/imunologia
7.
J Clin Endocrinol Metab ; 82(8): 2639-44, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9253347

RESUMO

Patients with autoimmune thyroid disease frequently have high affinity antibodies to thyroid peroxidase (TPO), although the role they play in disease pathogenesis is not known. We have previously prepared 37 monoclonal anti-TPO IgG kappa Fab fragments from two patients with Hashimoto's thyroiditis and demonstrated the similarity of these Fab sequences to those published previously, mainly derived from patients with Graves' disease. In this paper, we described epitope mapping of these Fabs using a previously characterized panel of murine monoclonal antibody (mAb) and show that the Fabs bind to two neighboring epitopes on native TPO. Although the epitope-mapping method differs from that used to characterize previously published TPO-reactive Fab sequences, it indicates a similarly restricted response to neighboring epitopes in both Graves' disease and Hashimoto's thyroiditis. The epitope mapping included mAb 47, which binds to a linear TPO peptide of known sequence in addition to native TPO. Although TPO-reactive Fab did not inhibit the binding of mAb 47, mAb 47 did inhibit the binding of Fab, indicating the likely site of the immunodominant region on native TPO. These results confirm the restricted nature of TPO antibody and further delineate the immunodominant region of native TPO as defined by the mAb.


Assuntos
Autoanticorpos/imunologia , Mapeamento de Epitopos , Fragmentos Fab das Imunoglobulinas/imunologia , Iodeto Peroxidase/imunologia , Tireoidite Autoimune/imunologia , Animais , Anticorpos Monoclonais/imunologia , Especificidade de Anticorpos , Sítios de Ligação de Anticorpos , Antígenos HLA-DR/análise , Humanos , Camundongos
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