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1.
Rev Sci Instrum ; 87(11): 11E309, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27910500

RESUMO

The present work concerns the development of a W sources assessment system in the framework of the tungsten-W environment in steady state tokamak project that aims at equipping the existing Tore Supra device with a tungsten divertor in order to test actively cooled tungsten Plasma Facing Components (PFCs) in view of preparing ITER operation. The goal is to assess W sources and D recycling with spectral, spatial, and temporal resolution adapted to the PFCs observed. The originality of the system is that all optical elements are installed in the vacuum vessel and compatible with steady state operation. Our system is optimized to measure radiance as low as 1016 Ph/(m2 s sr). A total of 240 optical fibers will be deployed to the detection systems such as the "Filterscope," developed by Oak Ridge National Laboratory (USA) and consisting of photomultiplier tubes and filters, or imaging spectrometers dedicated to Multiview analysis.

2.
Ann Oncol ; 27(5): 902-7, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26787238

RESUMO

BACKGROUND: The IFM2009-02 trial studied pomalidomide (4 mg daily, 21/28 versus 28/28) and dexamethasone in very advanced relapsed or refractory multiple myeloma (RRMM). We observed that 40% of patients had a prolonged progression-free survival (PFS) and subsequently overall survival (OS). We sought to analyze the characteristics of these patients and study the effect of long exposure to pomalidomide. DESIGN: We separated the studied population into two groups: 3 months to 1 year (<1 year) and more than 1 year (≥1 year) of treatment with pomalidomide and dexamethasone based on clinical judgment and historical control studies. We then analyzed the characteristics of patients according to duration of treatment. RESULTS: The overall response rate (ORR) for the <1-year group was 43%, the median PFS 4.6 months [95% confidence interval (95% CI) 3.8-6.4] with only 6% at 12 months, and the median OS was 15 months (11.7-20.3) and 40% at 18 months. For the ≥1-year group, the response rate and survival were strikingly different, ORR at 83%, median PFS 20.7 months (14.7-35.4), median OS not reached, and 91% at 18 months. CONCLUSION: Pomalidomide and dexamethasone favored prolonged and safe exposure to treatment in 40% of heavily treated and end-stage RRMM, a paradigm shift in the natural history of RRMM characterized with a succession of shorter disease-free intervals and ultimately shorter survival. Although an optimization of pomalidomide-dexamethasone regimen is warranted in advanced RRMM, we claim that pomalidomide has proven once more to change the natural history of myeloma in this series, which should be confirmed in a larger study.


Assuntos
Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Mieloma Múltiplo/tratamento farmacológico , Recidiva Local de Neoplasia/tratamento farmacológico , Talidomida/análogos & derivados , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Bortezomib/administração & dosagem , Bortezomib/efeitos adversos , Dexametasona/administração & dosagem , Dexametasona/efeitos adversos , Intervalo Livre de Doença , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/patologia , Recidiva Local de Neoplasia/patologia , Talidomida/administração & dosagem , Talidomida/efeitos adversos
3.
Rev Sci Instrum ; 85(11): 11E301, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25430306

RESUMO

An exploratory study was carried out in the long-pulse tokamak Tore Supra, to determine if electric fields in the plasma around high-power, RF wave launchers could be measured with non-intrusive, passive, optical emission spectroscopy. The focus was in particular on the use of the external electric field Stark effect. The feasibility was found to be strongly dependent on the spatial extent of the electric fields and overlap between regions of strong (>∼1 kV/cm) electric fields and regions of plasma particle recycling and plasma-induced, spectral line emission. Most amenable to the measurement was the RF electric field in edge plasma, in front of a lower hybrid heating and current drive launcher. Electric field strengths and direction, derived from fitting the acquired spectra to a model including time-dependent Stark effect and the tokamak-range magnetic field Zeeman-effect, were found to be in good agreement with full-wave modeling of the observed launcher.

4.
Leukemia ; 28(3): 675-9, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23892719

RESUMO

Deletions of the 1p region appear as a pejorative prognostic factor in multiple myeloma patients (especially 1p22 and 1p32 deletions) but there is a lack of data on the real impact of 1p abnormalities on an important and homogeneous group of patients. To address this issue we studied by fluorescence in situ hybridization (FISH) the incidence and prognostic impact of 1p22 and 1p32 deletions in 1195 patients from the IFM (Institut Francophone du Myélome) cell collection. Chromosome 1p deletions were present in 23.3% of the patients (271): 15.1% (176) for 1p22 and 7.3% (85) for 1p32 regions. In univariate analyses, 1p22 and 1p32 appeared as negative prognostic factors for progression-free survival (PFS): 1p22: 19.8 months vs 33.6 months (P<0.001) and 1p32: 14.4 months vs 33.6 months (P<0.001); and overall survival (OS): 1p22: 44.2 months vs 96.8 months (P=0.002) and 1p32: 26.7 months vs 96.8 months (P<0.001). In multivariate analyses, 1p22 and 1p32 deletions still appear as independent negative prognostic factors for PFS and OS. In conclusion, our data show that 1p22 and 1p32 deletions are major negative prognostic factors for PFS and OS for patients with MM. We thus suggest that 1p32 deletion should be tested for all patients at diagnosis.


Assuntos
Deleção Cromossômica , Cromossomos Humanos Par 1 , Mieloma Múltiplo/genética , Estudos de Coortes , Feminino , Humanos , Hibridização in Situ Fluorescente , Masculino , Mieloma Múltiplo/patologia , Prognóstico
5.
Phys Rev Lett ; 110(21): 215005, 2013 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-23901403

RESUMO

Fully dynamic Stark effect visible spectroscopy was used for the first time to directly measure the local rf electric field in the boundary plasma near a high-power antenna in high-performance, magnetically confined, fusion energy experiment. The measurement was performed in the superconducting tokamak Tore Supra, in the near field of a 1­3 MW, lower-hybrid, 3.7 GHz wave-launch antenna, and combined with modeling of neutral atom transport to estimate the local rf electric field amplitude (as low as 1­2 kV/cm) and direction in this region. The measurement was then shown to be consistent with the predicted values from a 2D full-wave propagation model. Notably the measurement confirmed that the electric field direction deviates substantially from the direction in which it is launched by the waveguides as it penetrates only a few cm radially inward into the plasma from the waveguides, consistent with the model.

7.
Rev Sci Instrum ; 81(10): 10E104, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21033969

RESUMO

A shielded residual gas analyzer (RGA) system on Tore Supra can function during plasma operation and is set up to monitor the composition of the neutral gas in one of the pumping ducts of the toroidal pumped limited. This "diagnostic RGA" has been used in long-pulse (up to 6 min) discharges for continuous monitoring of up to 15 masses simultaneously. Comparison of the RGA-measured evolution of the H(2)/D(2) isotopic ratio in the exhaust gas to that measured by an energetic neutral particle analyzer in the plasma core provides a way to monitor the evolution of particle balance. RGA monitoring of corrective H(2) injection to maintain proper minority heating is providing a database for improved ion cyclotron resonance heating, potentially with RGA-base feedback control. In very long pulses (>4 min) absence of significant changes in the RGA-monitored, hydrocarbon particle pressures is an indication of proper operation of the actively cooled, carbon-based plasma facing components. Also H(2) could increase due to thermodesorption of overheated plasma facing components.

9.
Phys Rev Lett ; 91(20): 205002, 2003 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-14683368

RESUMO

A pellet penetrating the inner region of a tokamak discharge, where the safety factor drops below unity, triggers an instability analogous to a sawtooth crash. Because of the simultaneity of the crash and pellet crossing, the latter is an appropriate probe for investigating the current distribution during reconnection. In this Letter, pellet deflection is used to characterize the associated electron distribution function. The perturbation compatible with the observed trajectory requires a negative current layer on the q=1 magnetic surface between 3 and 12 times the equilibrium current density and an expulsion of high energy electrons from the plasma core.

10.
Phys Rev Lett ; 90(15): 155002, 2003 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-12732041

RESUMO

Recently, plasmas exceeding 4 min have been obtained with lower hybrid current drive (LHCD) in Tore Supra. These LHCD plasmas extend for over 80 times the resistive current diffusion time with zero loop voltage. Under such unique conditions the neoclassical particle pinch driven by the toroidal electric field vanishes. Nevertheless, the density profile remains peaked for more than 4 min. For the first time, the existence of an inward particle pinch in steady-state plasma without toroidal electric field, much larger than the value predicted by the collisional neoclassical theory, is experimentally demonstrated.

11.
Phys Rev Lett ; 84(24): 5532-5, 2000 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-10990987

RESUMO

In reversed-field pinches, two different mechanisms have been proposed to explain the dynamo process which drives the poloidal current needed to sustain the magnetic configuration: the kinetic dynamo theory and the magnetohydrodynamic (MHD) dynamo theory. Experimentally, they can be distinguished by the radial behavior of the electron distribution function. In this Letter the trajectory deflection of frozen hydrogen pellets has been used as a diagnostic of suprathermal electrons in the plasma. The classical Spitzer-Harm distortion of the electron distribution function consistent with the MHD dynamo electric field is found to give a better modeling of the pellet trajectory.

13.
Blood ; 88(7): 2480-7, 1996 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-8839839

RESUMO

We performed a randomized study of hydroxyurea (HY) versus VP16 in advanced chronic myelomonocytic leukemia (CMML) patients with CMML (according to French-American-British group criteria) and either documented visceral involvement (excluding liver and spleen infiltration) or at least 2 of the following: (1) neutrophils > 16 x 10(9)/I (2) Hemoglobin < 10 g/dL (3) platelets < 100 x 10(9)/L (4) marrow blasts > 5% (5) spleen > 5 cm below costal margin were eligible for this trial. Initial dosage was 1 g/d for HY and 150 mg/week for VP16, orally (doubled in case of visceral involvement). Doses were scheduled to be escalated up to HY 4 g/d and VP16 600 mg/week in the absence of response, and finally adjusted to maintain white blood cells (WBCs) between 5 and 10 x 10(9)/L. Crossing over was scheduled only in case of life threatening visceral involvement or major progression. The major endpoint of the study was survival. The study was closed on first interim analysis that showed a superiority of HY over VP16, after inclusion of 105 pts (HY arm: 53, VP16 arm: 52). Results of the second interim analysis, performed 7 months later, are presented here. Median age was 71 (range 38 to 91), median WBC count 20.10(9)/L (range 10 to 187). Thirteen pts had visceral involvement (3 serous effusions, 8 cutaneous infiltrations, 1 kidney, 1 bone infiltrations). Initial characteristics were similar in the HY and VP16 groups. Median follow up was 11 months in both groups (range 1 to 43+). Response to treatment was seen in 60% of the pts in the HY group, versus 36%, respectively, in the VP16 group (P = .02). Time to response was significantly shorter in the HY group (2.1 v 3.5 months, in the VP16 group, P = .003) and response duration was significantly longer in the HY group (median 24 v 9 months, in the VP16 group, P = .0004). The response rate of patients with visceral involvement was 3 out of 7 in the VP16 arm versus 5 out of 6 in the HY group. Three of the 10 pts crossed over from HY to VP16 responded as compared to 6 pts of the 11 pts crossed over from VP16 to HY. HY yielded better response on leukocytosis (P = .002). The effect on splenomegaly platelets, on hemoglobin level and transfusion requirement was similar in the 2 treatment groups. A significantly higher incidence of alopecia was noted in the VP16 arm (20% v 3%, P = .03). Fourteen (27%) and 20 (38%) patients in the HY and the VP16 group respectively, progressed to acute myeloid leukemia (difference NS). Twenty five (53%) and 44 (83%) patients in the HY and the VP16 group, respectively, had died (P = .002). Median actuarial survival was 20 months in the HY arm, versus 9 months in the VP16 arm (P < 10(-4)). Main factors associated with poor survival were allocation to the VP16 arm, "unfavorable" karyotype (ie, monosomy 7 or complex abnormalities) and anemia. In the HY group, unfavorable karyotype (P = .006), and low hemoglobin level (P = .004) were significantly associated with low response rates. Prognostic factors for poor survival in the HY group were also unfavorable karyotype (P = .001), and low hemoglobin level (P < 10(-4). In conclusion, we found that HY gave higher response rates and better survival than VP16 in advanced CMML. However, even with HY responses were only partial and survival was generally poor. This stresses the need for new agents in the treatment of CMML, that will have to be compared with HY in future randomized studies.


Assuntos
Etoposídeo/uso terapêutico , Hidroxiureia/uso terapêutico , Leucemia Mielomonocítica Crônica/tratamento farmacológico , Adulto , Idoso , Alopecia/induzido quimicamente , Contagem de Células Sanguíneas/efeitos dos fármacos , Estudos Cross-Over , Etoposídeo/efeitos adversos , Feminino , Humanos , Hidroxiureia/efeitos adversos , Cariotipagem , Leucemia Mielomonocítica Crônica/genética , Leucemia Mielomonocítica Crônica/mortalidade , Tábuas de Vida , Masculino , Pessoa de Meia-Idade , Prognóstico , Fatores de Risco , Esplenomegalia/tratamento farmacológico , Esplenomegalia/etiologia , Análise de Sobrevida , Resultado do Tratamento
14.
J Rheumatol ; 19(1): 146-52, 1992 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-1556678

RESUMO

Initial signs of malignant lymphoma are rarely due to bone lesions. We reviewed 6 cases with early skeletal involvement, recently observed in the rheumatology and hematology departments. In 3 patients, magnetic resonance imaging (MRI) was added to traditional investigations, including radiography, radionuclide bone scan and computerized tomography. We stress the possibility of bone involvement in the clinical onset of malignant lymphoma and the usefulness of early bone assessment using MRI.


Assuntos
Osso e Ossos/patologia , Doença de Hodgkin/diagnóstico , Adulto , Osso e Ossos/diagnóstico por imagem , Feminino , Doença de Hodgkin/diagnóstico por imagem , Doença de Hodgkin/patologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Cintilografia , Tomografia Computadorizada por Raios X
15.
Br J Haematol ; 74(4): 432-8, 1990 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1693285

RESUMO

The possible role of T lymphocytes in the formation of granulomatous reactions seen in certain malignant lymphoid tumours was investigated by measuring the granulopoietic colony-stimulating activity (CSA) and granulopoietic-inhibiting activity (IA) produced by stimulated T-lymphocytes isolated from peripheral blood, spleen and lymph nodes of patients and normal subjects. Lymph-node T-cells from patients with benign lymphoid hyperplasia, B-cell non-Hodgkin's lymphoma (B-NHL), and non-granulomatous Hodgkin's disease (HD) showed no CSA, but the cells produced IA of 40 +/- 23%, 40 +/- 24% and 50.5 +/- 22.5% respectively. The corresponding cells from patients with HD accompanied by granulomatous reactions produced CSA of 6.85 +/- 6.5 u/microliters and IA of 23.5 +/- 21%. The presence of a granulomatous reaction in malignant lymphoma was correlated with the stimulation of granulopoiesis in vitro by T lymphocytes associated with malignant cells. A correlation was demonstrated between neutrophilic and eosinophilic colonies obtained in vitro under the influence of CSA-producing T cells isolated from malignant lymphomas and the neutrophils and eosinophils present in the granuloma. These results showed that tumour-infiltrating T cells play a role in the presence of granulomatous reactions seen in lymphomas. Peripheral-blood T cells from healthy subjects, and from patients with B-NHL, or with HD unaccompanied by granulocytic reactions produced CSAs of, respectively, 5 +/- 0.5 u/microliter, 4.8 +/- 2.2 u/microliters and 5.3 +/- 0.4 u/microliters, and IAs of 45 +/- 18%. 50 +/- 5.5% and 50.5 +/- 7% respectively. The corresponding values for HD patients with granulocytic reactions were CSA. 17 +/- 15.5 u/microliters, and IA, 9.5 +/- 9%. No correlation was demonstrated between neutrophilic colonies obtained in vitro under the influence of HD blood T cells and neutrophils present in blood. Only one correlation was found: between the percentage of eosinophilic colonies and the number of blood eosinophils. HD blood T cells did not seem to explain completely granulocytic reactions seen in blood.


Assuntos
Fatores Estimuladores de Colônias/biossíntese , Linfoma/imunologia , Biossíntese de Proteínas , Proteínas , Linfócitos T/metabolismo , Linfócitos B/imunologia , Fator Estimulador de Colônias de Granulócitos , Doença de Hodgkin/imunologia , Humanos , Hiperplasia/imunologia , Linfonodos/patologia , Linfoma/sangue , Linfoma não Hodgkin/patologia
16.
Nouv Rev Fr Hematol (1978) ; 32(2): 165-6, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2377449

RESUMO

We report the positive effect of danazol on clinical and hematological data in a patient with myelofibrosis and myeloid metaplasia. Severe cytopenia was corrected within 2 months and was maintained for an additional 2-month period. Myeloid metaplasia (lymph nodes and skin lesions) was greatly reduced. The patient experienced no side effects. We propose further trials to confirm the utility of this agent in this disease.


Assuntos
Danazol/uso terapêutico , Pregnadienos/uso terapêutico , Mielofibrose Primária/tratamento farmacológico , Humanos , Masculino , Pessoa de Meia-Idade , Mielofibrose Primária/complicações
18.
Rev Rhum Mal Osteoartic ; 56(11): 745-51, 1989 Nov.
Artigo em Francês | MEDLINE | ID: mdl-2609087

RESUMO

Bone localizations revealing Hodgkin's disease or non-Hodgkin's malignant lymphoma, are unusual. We are reporting 11 recent cases collected in rheumatology and haematology departments, including 4 where a comprehensive study of X-rays, scintigrams, axial tomograms and nuclear magnetic resonance imaging was performed. Review of the literature as well as our experience concerning the type of onset of the bone involvement, the clinical correlation, the imaging techniques, have led us to consider nuclear magnetic resonance as a decisive factor which should be offered at an early stage in the diagnostic approach.


Assuntos
Neoplasias Ósseas/secundário , Doença de Hodgkin/diagnóstico , Linfoma não Hodgkin/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Ósseas/complicações , Neoplasias Ósseas/diagnóstico , Feminino , Doença de Hodgkin/patologia , Humanos , Linfoma não Hodgkin/patologia , Espectroscopia de Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Síndromes de Compressão Nervosa/etiologia , Ciática/etiologia , Compressão da Medula Espinal/etiologia , Tomografia Computadorizada por Raios X
19.
Leuk Res ; 13(4): 323-9, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2785619

RESUMO

Total T lymphocytes separated from twelve lymph nodes involved by B-NHL were studied in limiting dilution experiments for their ability to proliferate in the presence of both R-IL2 used at a final concentration of 40 U/ml and irradiated autologous malignant B cells as feeders. The number of proliferating T-lymphocyte precursors (PTL-P) thus estimated was low in each case (mean: 1/4503; range, 1/200 to 1/11013). Once expanded, proliferation of the IL2 responsive T cells in the presence of autologous malignant B cells remained strictly dependent on the addition of exogenous IL2. Control cases consisted of T lymphocytes separated from peripheral blood of six healthy subjects and cultured in the presence of both R-IL2 (40 U/ml) and irradiated autologous total mononuclear cells as feeders; the mean frequency of PTL-P thus obtained (1/173; range, 1/49 to 1/457) was significantly higher than in malignant lymph nodes (p less than 0.01). These findings do not support the hypothesis that, in this series of patients, expansion of malignant B cells may lead to the activation and growth of T cells sensitized against the tumour.


Assuntos
Interleucina-2/farmacologia , Leucemia de Células B/imunologia , Contagem de Leucócitos , Ativação Linfocitária , Linfoma não Hodgkin/imunologia , Linfócitos T/imunologia , Antígenos de Diferenciação de Linfócitos T/análise , Humanos , Interleucina-2/fisiologia , Linfonodos , Fenótipo , Proteínas Recombinantes/farmacologia , Células-Tronco/imunologia , Linfócitos T/classificação
20.
Cancer ; 61(10): 2057-9, 1988 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-3282641

RESUMO

In two centers (a comprehensive cancer center and a university hospital) 1300 patients with non-Hodgkin's lymphomas (NHL) were observed during the past 15 years. Seventy patients (5.4%) were diagnosed after they were 80 years old. Thirty-four patients had low-grade NHL, eight had intermediate grade, and 28 had high-grade NHL. The majority of them were classified as Stage I (n = 24) or II (n = 18), and the rest as Stage III (n = 16) or IV (n = 12). Treatment varied with grade of NHL, tumoral extension, and performance status. Forty-seven patients were given chemotherapy, 37 radiotherapy, and six patients had surgery. Overall, treatment was considered to be optimal in 12 patients, good in 34 patients, and limited in 24 patients. Toxicity was minimal in 62 patients, treatment-limiting in two patients, and lethal in six patients. Thirty-seven patients achieved a complete remission (CR), 21 a partial remission, five experienced stabilization, and seven failed to respond. For all patients, the median survival (MS) was 18 months. In contrast to younger patients, malignancy grade had no significant influence. The only significant parameter is CR (P = 0.02). In conclusion, very old patients must be treated correctly but carefully. Better tolerated treatments are needed to improve results that are neither very poor nor as good as in younger patients.


Assuntos
Linfoma não Hodgkin/patologia , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Terapia Combinada , Feminino , França , Humanos , Linfoma não Hodgkin/mortalidade , Linfoma não Hodgkin/terapia , Masculino , Estudos Retrospectivos
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