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2.
Nature ; 481(7382): 480-3, 2012 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-22281596

RESUMO

The standard model for the origin of galactic magnetic fields is through the amplification of seed fields via dynamo or turbulent processes to the level consistent with present observations. Although other mechanisms may also operate, currents from misaligned pressure and temperature gradients (the Biermann battery process) inevitably accompany the formation of galaxies in the absence of a primordial field. Driven by geometrical asymmetries in shocks associated with the collapse of protogalactic structures, the Biermann battery is believed to generate tiny seed fields to a level of about 10(-21) gauss (refs 7, 8). With the advent of high-power laser systems in the past two decades, a new area of research has opened in which, using simple scaling relations, astrophysical environments can effectively be reproduced in the laboratory. Here we report the results of an experiment that produced seed magnetic fields by the Biermann battery effect. We show that these results can be scaled to the intergalactic medium, where turbulence, acting on timescales of around 700 million years, can amplify the seed fields sufficiently to affect galaxy evolution.

3.
Am J Transplant ; 16(9): 2532-44, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-26932352

RESUMO

Both acute and chronic kidney disease are common after liver transplantation and result in significant morbidity and mortality. The introduction of the Model for End-stage Liver Disease score has directly correlated with an increased prevalence of perioperative renal dysfunction and the number of simultaneous liver-kidney transplantations performed. Kidney dysfunction in this population is typically multifactorial and related to preexisting conditions, pretransplantation renal injury, perioperative events, and posttransplantation nephrotoxic immunosuppressive therapies. The management of kidney disease after liver transplantation is challenging, as by the time the serum creatinine level is significantly elevated, few interventions affect the course of progression. Also, immunological factors such as antibody-mediated kidney rejection have become of greater interest given the rising liver-kidney transplant population. Therefore, this review, assembled by experts in the field and endorsed by the American Society of Transplantation Liver and Intestine Community of Practice, provides a critical assessment of measures of renal function and interventions aimed at preserving renal function early and late after liver and simultaneous liver-kidney transplantation. Key points and practice-based recommendations for the prevention and management of kidney injury in this population are provided to offer guidance for clinicians and identify gaps in knowledge for future investigations.


Assuntos
Intestinos/transplante , Falência Renal Crônica/prevenção & controle , Transplante de Fígado/efeitos adversos , Guias de Prática Clínica como Assunto/normas , Humanos , Falência Renal Crônica/etiologia , Sociedades Médicas
5.
J Thromb Thrombolysis ; 41(2): 312-20, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26091712

RESUMO

Bleeding-prediction scores may help guiding management of patients with pulmonary embolism (PE), although no such score has been validated. We aimed to externally validate and compare two bleeding-prediction scores for venous thromboembolism to three scores developed for patients with atrial fibrillation in a real-world cohort of PE patients. We performed a prospective observational cohort study in 448 consecutive PE patients who were treated with heparins followed by vitamin-K-antagonists. The Kuijer, RIETE, HEMORR2HAGES, HAS-BLED and ATRIA scores were assessed at baseline. All patients were followed for the occurrence of major bleeding over a 30-day period. The accuracies of both the overall, original 3-level and newly defined optimal 2-level outcome of the scores were evaluated and compared, both for the 30-day period as well as for bleeding occurring in versus after the first week of treatment. 20 of 448 patients suffered major bleeding resulting in a cumulative incidence of 4.5 % (95 % CI 2.5-6.5). The predictive power of all five scores for bleeding was poor (c-statistics 0.57-0.64), both for the 3-level and 2-level score outcomes. No individual score was found to be superior. The HAS-BLED score had a good c-statistic for bleedings occurring after the first week of treatment (0.75, 95 % CI 0.47-1.0). Current available scoring systems have insufficient accuracy to predict overall anticoagulation-associated bleeding in patients treated for acute PE. To optimally target bleeding-prevention strategies, the development of a high quality PE-specific risk score is urgently needed.


Assuntos
Hemorragia , Heparina , Embolia Pulmonar , Sistema de Registros , Vitamina K/antagonistas & inibidores , Doença Aguda , Idoso , Idoso de 80 Anos ou mais , Feminino , Hemorragia/sangue , Hemorragia/induzido quimicamente , Hemorragia/mortalidade , Heparina/administração & dosagem , Heparina/efeitos adversos , Humanos , Masculino , Valor Preditivo dos Testes , Estudos Prospectivos , Embolia Pulmonar/sangue , Embolia Pulmonar/tratamento farmacológico , Embolia Pulmonar/mortalidade , Medição de Risco
6.
Am J Transplant ; 15(8): 2152-8, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25904248

RESUMO

Our objective was to evaluate the impact of hydroxyethyl starch (HES) use in organ donors after neurologic determination of death (DNDD) on recipient renal graft outcomes. The following data elements were prospectively collected for every DNDD managed by a single organ procurement organization from June 2011 to July 2013: demographics; critical care endpoints; treatments, including the use of HES; graft cold ischemia time (CIT); and the occurrence of recipient delayed graft function (DGF, dialysis in the first week after transplantation). Logistic regression was performed to identify independent predictors of DGF with a p-value <0.05. The results were then adjusted for each donor's calculated propensity to receive HES. Nine hundred eighty-six kidneys were transplanted from 529 donors. Forty-two percent received HES (1217 ± 528 mL) and 35% developed DGF. Kidneys from DNDDs who received HES had a higher crude rate of DGF (41% vs. 31%, p < 0.001). After accounting for the propensity to receive HES, independent predictors of DGF were age (OR 1.02 [1.01-1.04] per year), CIT (OR 1.04[1.02-1.06] per hour), creatinine (OR 1.5 [1.32-1.72] per mg/dL) and HES use (OR 1.41 [1.02-1.95]). HES use during donor management was independently associated with a 41% increase in the risk of DGF in kidney transplant recipients.


Assuntos
Derivados de Hidroxietil Amido/administração & dosagem , Transplante de Rim , Doadores de Tecidos , Adulto , Humanos , Testes de Função Renal
7.
Am J Transplant ; 13(1): 184-91, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23126562

RESUMO

Over the last decade the age of liver transplant (LT) recipients and the likelihood of coronary artery disease (CAD) in this population have increased. There are no multicenter studies that have examined the impact of CAD on LT outcomes. In this historical cohort study, we identified adult LT recipients who underwent angiography prior to transplantation at seven institutions over a 12-year period. For each patient we recorded demographic data, recipient and donor risk factors, duration of follow-up, the presence of angiographically proven obstructive CAD (≥50% stenosis) and post-LT survival. Obstructive CAD was present in 151 of 630 patients, the CAD(+) group. Nonobstructive CAD was found in 479 patients, the CAD(-) group. Patient survival was similar for the CAD(+) group (adjusted HR 1.13, CI = [0.79, 1.62], p = 0.493) compared to the CAD(-) group. The CAD(+) patients were further stratified into severe (CADsev, >70% stenosis, n = 96), and moderate CAD (CADmod, 50-70% stenosis, n = 55) groups. Survival for the CADsev (adjusted HR = 1.26, CI = [0.83, 1.91], p = 0.277) and CADmod (adjusted HR = 0.93, CI = [0.52, 1.66], p = 0.797) groups were similar to the CAD(-) group. We conclude that when current CAD treatment strategies are employed prior to transplant, post-LT survival is not significantly different between patients with and without obstructive CAD.


Assuntos
Angiografia Coronária , Doença da Artéria Coronariana/complicações , Transplante de Fígado , Resultado do Tratamento , Idoso , Doença da Artéria Coronariana/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco
8.
Acta Anaesthesiol Scand ; 57(4): 518-25, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23336265

RESUMO

AIMS: This prospective, cross-sectional study aimed to assess cancer pain and its management in an inpatient setting at a comprehensive cancer centre in Denmark. METHODS: One hundred and eighty-eight inpatients with cancer were invited to participate (May/June 2011). Demographics, diagnoses, World Health Organization performance status, health-related quality of life, pain and data regarding analgesic treatment were registered. RESULTS: One hundred and thirty-four (71.3%) patients agreed to participate in the study. Most frequent diagnoses were leukaemia (27.6%) and lung cancer (14.2%). A high prevalence of pain was observed, 65.7%. Thirty-two per cent reported moderate to severe pain when it was at its worst, 96% reported no or mild pain when it was at its least. Nearly 22% reported moderate to severe pain when the pain was categorised as average. Breakthrough pain episodes were reported by 30.5%. Adjuvant medication was sparsely used and not always correctly indicated. Out of 88 patients with pain, 62.5% were left untreated according to the Electronic Medication System. Higher health-related quality of life was associated with lower pain intensity. The use of opioids with or without adjuvants was associated with higher pain intensity and higher number of breakthrough pain episodes. CONCLUSIONS: Approximately two thirds of inpatients reported pain and one third had breakthrough pain. A substantial number of patients with pain were left untreated. Opioid-treated patients reported highest pain intensity and number of breakthrough episodes; however, analgesic medication seemed to be underused. Measures to improve pain assessment and management are highly required.


Assuntos
Neoplasias/fisiopatologia , Dor Intratável/tratamento farmacológico , Adulto , Idoso , Analgésicos Opioides/uso terapêutico , Dor Irruptiva/tratamento farmacológico , Estudos Transversais , Feminino , Humanos , Pacientes Internados , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
9.
Rev Sci Instrum ; 93(10): 103518, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-36319323

RESUMO

We present measurements of ion velocity distribution profiles obtained by laser induced fluorescence (LIF) on an explosive laser produced plasma. The spatiotemporal evolution of the resulting carbon ion velocity distribution was mapped by scanning through the Doppler-shifted absorption wavelengths using a tunable, diode-pumped laser. The acquisition of these data was facilitated by the high repetition rate capability of the ablation laser (1 Hz), which allowed for the accumulation of thousands of laser shots in short experimental times. By varying the intensity of the LIF beam, we were able to explore the effects of fluorescence power against the laser irradiance in the context of evaluating the saturation vs the non-saturation regime. The small size of the LIF beam led to high spatial resolution of the measurement compared to other ion velocity distribution measurement techniques, while the fast-gate operation mode of the camera detector enabled the measurement of the relevant electron transitions.

10.
Rev Sci Instrum ; 93(8): 083514, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-36050046

RESUMO

We have developed a non-collective Thomson scattering diagnostic for measurements of electron density and temperature on the Large Plasma Device. A triple grating spectrometer with a tunable notch filter is used to discriminate the faint scattering signal from the stray light. In this paper, we describe the diagnostic and its calibration via Raman scattering and present the first measurements performed with the fully commissioned system. Depending on the discharge conditions, the measured densities and temperatures range from 4.0 × 1012 to 2.8 × 1013 cm-3 and from 1.2 to 6.8 eV, respectively. The variation of the measurement error with plasma parameters and discharges averaged is also discussed.

11.
Rev Sci Instrum ; 92(9): 093102, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34598480

RESUMO

We present optical Thomson scattering measurements of electron density and temperature in a large-scale (∼2 cm) exploding laser plasma produced by irradiating a solid target with a high-energy (5-10 J) laser pulse at a high repetition rate (1 Hz). The Thomson scattering diagnostic matches this high repetition rate. Unlike previous work performed in single shots at much higher energies, the instrument allows for point measurements anywhere inside the plasma by automatically translating the scattering volume using motorized stages as the experiment is repeated at 1 Hz. Measured densities around 4 × 1016 cm-3 and temperatures around 7 eV result in a scattering parameter near unity, depending on the distance from the target. The measured spectra show the transition from collective scattering close to the target to non-collective scattering at larger distances. Densities obtained by fitting the weakly collective spectra agree to within 10% with an irradiance calibration performed via Raman scattering in nitrogen.

12.
Bone Marrow Transplant ; 56(6): 1413-1421, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33452448

RESUMO

We report the 12-year follow-up of the prospective randomized EBMT LYM1 trial to determine whether the benefit of brief duration rituximab maintenance (RM) on progression-free survival (PFS) in patients with relapsed follicular lymphoma (FL) receiving an autologous stem cell transplant (ASCT) is sustained. One hundred and thirty-eight patients received RM with or without purging. The median follow-up after random assignment is 12 years (range 10-13) for the whole series. The 10-year PFS after ASCT is 47% (95% CI 40-54) with only 4 patients relapsing after 7.5 years. RM continues to significantly improve 10-year PFS after ASCT in comparison with NM [P = 0.002; HR 0.548 (95% CI 0.38-0.80)]. Ten-year non-relapse mortality (NRM) was not significantly different between treatment groups (7% overall). 10-year overall survival (OS) after ASCT was 75% (69-81) for the whole series, with no significant differences according to treatment sub-groups. 10-year OS for patients who progressed within 24 months (POD24T) was 60%, in comparison with 85% for patients without progression. Thus the benefit of rituximab maintenance after ASCT on relapse prevention is sustained at 12 years, suggesting that RM adds to ASCT-mediated disease eradication and may enhance the curative potential of ASCT.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Linfoma Folicular , Protocolos de Quimioterapia Combinada Antineoplásica , Autoenxertos , Terapia Combinada , Seguimentos , Humanos , Linfoma Folicular/tratamento farmacológico , Recidiva Local de Neoplasia , Estudos Prospectivos , Estudos Retrospectivos , Rituximab/uso terapêutico , Transplante Autólogo
13.
Phys Rev Lett ; 105(7): 075003, 2010 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-20868053

RESUMO

We present the first measurements of the plasmon dispersion and damping in laser shock-compressed solid matter. Petawatt laser produced K-α radiation scatters on boron targets compressed by a 10 ns-long 400 J laser pulse. In the vicinity of the Fermi momentum, the scattering spectra show dispersionless, collisionally damped plasmons, indicating a strongly coupled electron liquid. These observations agree with calculations that include the Born-Mermin approximation to account for electron-ion collisional damping and local field corrections reflecting electron-electron correlations.

14.
Phys Rev Lett ; 105(26): 265701, 2010 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-21231678

RESUMO

Laser-produced proton beams have been used to achieve ultrafast volumetric heating of carbon samples at solid density. The isochoric melting of carbon was probed by a scattering of x rays from a secondary laser-produced plasma. From the scattering signal, we have deduced the fraction of the material that was melted by the inhomogeneous heating. The results are compared to different theoretical approaches for the equation of state which suggests modifications from standard models.

15.
Rev Sci Instrum ; 91(10): 103103, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-33138584

RESUMO

Laser-produced plasma velocity distributions are an important, but difficult quantity to measure. We present a non-invasive technique for measuring individual charge state velocity distributions of laser-produced plasmas using a high temporal and spectral resolution monochromator. The novel application of this technique is its ability to detect particles up to 7 m from their inception (significantly larger than most laboratory plasma astrophysics experiments, which take place at or below the millimeter scale). The design and assembly of this diagnostic is discussed in terms of maximizing the signal to noise ratio, maximizing the spatial and temporal resolution, and other potential use cases. The analysis and results of this diagnostic are demonstrated by directly measuring the time-of-flight velocity of all ion charge states in a laser produced carbon plasma.

16.
J Cell Biol ; 143(2): 533-45, 1998 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-9786961

RESUMO

We have established a cell culture system that reproduces morphogenic processes in the developing mammary gland. EpH4 mouse mammary epithelial cells cultured in matrigel form branched tubules in the presence of hepatocyte growth factor/scatter factor (HGF/SF), the ligand of the c-met tyrosine kinase receptor. In contrast, alveolar structures are formed in the presence of neuregulin, a ligand of c-erbB tyrosine kinase receptors. These distinct morphogenic responses can also be observed with selected human mammary carcinoma tissue in explant culture. HGF/SF-induced branching was abrogated by the PI3 kinase inhibitors wortmannin and LY294002. In contrast, neuregulin- induced alveolar morphogenesis was inhibited by the MAPK kinase inhibitor PD98059. The c-met-mediated response could also be evoked by transfection of a c-met specific substrate, Gab1, which can activate the PI3 kinase pathway. An activated hybrid receptor that contained the intracellular domain of c-erbB2 receptor suffices to induce alveolar morphogenesis, and was observed in the presence of tyrosine residues Y1028, Y1144, Y1201, and Y1226/27 in the substrate-binding domain of c-erbB2. Our data demonstrate that c-met and c-erbB2 signaling elicit distinct morphogenic programs in mammary epithelial cells: formation of branched tubules relies on a pathway involving PI3 kinase, whereas alveolar morphogenesis requires MAPK kinase.


Assuntos
Glândulas Mamárias Animais/embriologia , Proteínas Proto-Oncogênicas c-met/fisiologia , Receptor ErbB-2/fisiologia , Transdução de Sinais/fisiologia , Androstadienos/farmacologia , Animais , Neoplasias da Mama , Proteínas Quinases Dependentes de Cálcio-Calmodulina/metabolismo , Moléculas de Adesão Celular/fisiologia , Cromonas/farmacologia , Inibidores Enzimáticos/farmacologia , Flavonoides/farmacologia , Glicoproteínas/fisiologia , Fator de Crescimento de Hepatócito/fisiologia , Humanos , Glândulas Mamárias Animais/citologia , Glândulas Mamárias Animais/enzimologia , Camundongos , Microscopia Eletrônica , Morfogênese/fisiologia , Morfolinas/farmacologia , Neurregulinas , Fosfatidilinositol 3-Quinases/metabolismo , Transdução de Sinais/efeitos dos fármacos , Células Tumorais Cultivadas/citologia , Células Tumorais Cultivadas/enzimologia , Células Tumorais Cultivadas/ultraestrutura , Wortmanina
17.
J Cell Biol ; 131(1): 215-26, 1995 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7559778

RESUMO

We have examined the role of two mesenchymal ligands of epithelial tyrosine kinase receptors in mouse mammary gland morphogenesis. In organ cultures of mammary glands, hepatocyte growth factor (HGF, scatter factor) promoted branching of the ductal trees but inhibited the production of secretory proteins. Neuregulin (NRG, neu differentiation factor) stimulated lobulo-alveolar budding and the production of milk proteins. These functional effects are paralleled by the expression of the two factors in vivo: HGF is produced in mesenchymal cells during ductal branching in the virgin animal; NRG is expressed in the mesenchyme during lobulo-alveolar development at pregnancy. The receptors of HGF and NRG (c-met, c-erbB3, and c-erbB4), which are expressed in the epithelial cells, are not regulated. In organ culture, branching morphogenesis and lobulo-alveolar differentiation of the mammary gland could be abolished by blocking expression of endogenous HGF and NRG by the respective antisense oligonucleotides; in antisense oligonucleotide-treated glands, morphogenesis could again be induced by the addition of recombinant HGF and NRG. We thus show that two major postnatal morphogenic periods of mammary gland development are dependent on sequential mesenchymal-epithelial interactions mediated by HGF and NRG.


Assuntos
Glicoproteínas/fisiologia , Fator de Crescimento de Hepatócito/fisiologia , Glândulas Mamárias Animais/citologia , Animais , Sequência de Bases , Diferenciação Celular/fisiologia , Células Epiteliais , Feminino , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Hibridização In Situ , Glândulas Mamárias Animais/embriologia , Camundongos , Camundongos Endogâmicos BALB C , Dados de Sequência Molecular , Morfogênese/fisiologia , Neurregulinas , Oligonucleotídeos Antissenso/farmacologia , Técnicas de Cultura de Órgãos
18.
Sci Rep ; 8(1): 8432, 2018 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-29849052

RESUMO

We present the first experimental measurement of temperature and density of a warm dense plasma produced by a pulsed power driver at the Nevada Terawatt Facility (NTF). In the early phases of discharge, most of the mass remains in the core, and it has been challenging to diagnose with traditional methods, e.g. optical probing, because of the high density and low temperature. Accurate knowledge of the transport coefficients as well as the thermodynamic state of the plasma is important to precisely test or develop theoretical models. Here, we have used spectrally resolved non-collective X-ray Thomson scattering to characterize the dense core region. We used a graphite load driven by the Zebra current generator (0.6 MA in 200 ns rise time) and the Ti He-α line produced by irradiating a Ti target with the Leopard laser (30 J, 0.8 ns) as an X-ray probing source. Using this configuration, we obtained a signal-to-noise ratio ~2.5 for the scattered signal. By fitting the experimental data with predicted spectra, we measured T = 2±1.9 eV, ρ = 0.6±0.5 gr/cc, 70 ns into the current pulse. The complexity of the dense core is revealed by the electrons in the dense core that are found to be degenerate and weakly coupled, while the ions remain highly coupled.

19.
Leukemia ; 32(5): 1070-1080, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29467486

RESUMO

In chronic lymphocytic leukemia (CLL), TP53 gene defects, due to deletion of the 17p13 locus and/or mutation(s) within the TP53 gene, are associated with resistance to chemoimmunotherapy and a particularly dismal clinical outcome. On these grounds, analysis of TP53 aberrations has been incorporated into routine clinical diagnostics to improve patient stratification and optimize therapeutic decisions. The predictive implications of TP53 aberrations have increasing significance in the era of novel targeted therapies, i.e., inhibitors of B-cell receptor (BcR) signaling and anti-apoptotic BCL2 family members, owing to their efficacy in patients with TP53 defects. In this report, the TP53 Network of the European Research Initiative on Chronic Lymphocytic Leukemia (ERIC) presents updated recommendations on the methodological approaches for TP53 mutation analysis. Moreover, it provides guidance to ensure that the analysis is performed in a timely manner for all patients requiring treatment and that the data is interpreted and reported in a consistent, standardized, and accurate way. Since next-generation sequencing technologies are gaining prominence within diagnostic laboratories, this report also offers advice and recommendations for the interpretation of TP53 mutation data generated by this methodology.


Assuntos
Análise Mutacional de DNA/métodos , Genes p53/genética , Leucemia Linfocítica Crônica de Células B/genética , Europa (Continente) , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos
20.
Rev Sci Instrum ; 87(11): 11E701, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27910524

RESUMO

We present optical Thomson scattering results that image for the first time in a single measurement the spatial transition from collective to non-collective scattering. Data were taken in the Phoenix laser laboratory at the University of California, Los Angeles. The Raptor laser was used to ablate a carbon plasma, which was diagnosed with the frequency-doubled Phoenix laser serving as a Thomson scattering probe. Scattered light was collected from the laser plasma up to 10 cm from the target surface and up to 10 us after ablation, and imaged with high spatial and spectral resolutions. The results show a strong Thomson collective feature close to the target surface that smoothly transitions to a non-collective feature over several mm.

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