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1.
Nano Lett ; 17(1): 186-193, 2017 01 11.
Artículo en Inglés | MEDLINE | ID: mdl-28073272

RESUMEN

Future multifunctional hybrid devices might combine switchable molecules and 2D material-based devices. Spin-crossover compounds are of particular interest in this context since they exhibit bistability and memory effects at room temperature while responding to numerous external stimuli. Atomically thin 2D materials such as graphene attract a lot of attention for their fascinating electrical, optical, and mechanical properties, but also for their reliability for room-temperature operations. Here, we demonstrate that thermally induced spin-state switching of spin-crossover nanoparticle thin films can be monitored through the electrical transport properties of graphene lying underneath the films. Model calculations indicate that the charge carrier scattering mechanism in graphene is sensitive to the spin-state dependence of the relative dielectric constants of the spin-crossover nanoparticles. This graphene sensor approach can be applied to a wide class of (molecular) systems with tunable electronic polarizabilities.

2.
Langmuir ; 30(30): 9028-35, 2014 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-25000178

RESUMEN

In this work, we report on the self-assembly of bimetallic CoFe carbide magnetic nanoparticles (MNPs) stabilized by a mixture of long chain surfactants. A dedicated setup, coupling dip coating and sputtering chamber, enables control of the self-assembly of MNPs from regular stripe to continuous thin films under inert atmosphere. The effects of experimental parameters, MNP concentration, withdrawal speed, amount, and nature of surfactants, as well as the surface state of the substrates are discussed. Magnetic measurements revealed that the assembled particles were not oxidized, confirming the high potentiality of our approach for the controlled deposition of highly sensitive MNPs.

3.
Leuk Lymphoma ; 40(5-6): 529-40, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11426526

RESUMEN

This prospective study was undertaken to evaluate the efficacy and toxicity of combination chemotherapy with alternating cycles of vincristine, doxorubicin and dexamethasone (VAD) and cyclophophamide, doxorubicin, etoposide and prednisone (CHEP) in patients over 60 years old with previously untreated and advanced non-Hodgkin's lymphoma (NHL) of intermediate- and high-grade malignancy. Eighty one consecutive, patients with NHL referred from April 1992 to October 1997 to GOELAMS centers were enrolled in this study and their outcome updated to June 1, 1999. Of 81 enrolled patients, 77 were eligible and assessable for response. The median age was 70 years (61 to 78), 85.7% were stage III or IV, 39% were of performance status > or = 2, 27.3% > or = 2 involved extra-nodal sites and 57.3% had higher LDH levels than normal. The immunophenotype was B in 87% and T in 13%. Fifty-one (66.2%) patients received the scheduled eight cycles of therapy and treatment was withdrawn in only 6 patients (7.8%) because of toxicity. Neutropenia grade 3-4 occurred in 11.1% after VAD courses vs 40.6% after CHEP courses. The mean cumulative dose of doxorubicin was 269 mg/m2 and the relative dose intensity was 84%. The overall response and complete response rates were 66.2% and 51.9% respectively, and after a median follow-up of 52 months the 3 year overall survival (OS) and event-free survival rates (EFS) were 43.5% and 33.0% respectively. In multivariate analysis, OS and EFS were statistically influenced by IPI (p = 3 x 10(-3); p < 1 x 10(-4)) and phenotype (p = 2 x 10(-3); p < 1 x 10(-4)). Our findings support the alternation of 4 courses of VAD and CHEP as it is well tolerated in patients over 60 years old with advanced intermediate- or high-grade NHL and provides response and survival rates comparable to 6 courses of CHOP.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Linfoma no Hodgkin/tratamiento farmacológico , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Ciclofosfamida/administración & dosificación , Ciclofosfamida/efectos adversos , Dexametasona/administración & dosificación , Dexametasona/efectos adversos , Doxorrubicina/administración & dosificación , Doxorrubicina/efectos adversos , Etopósido/administración & dosificación , Etopósido/efectos adversos , Femenino , Humanos , Infusiones Intravenosas , Linfoma no Hodgkin/mortalidad , Linfoma no Hodgkin/patología , Masculino , Persona de Mediana Edad , Prednisona/administración & dosificación , Prednisona/efectos adversos , Estudios Prospectivos , Análisis de Supervivencia , Vincristina/administración & dosificación , Vincristina/efectos adversos
4.
J Chromatogr A ; 995(1-2): 87-97, 2003 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-12800925

RESUMEN

There is a need for a better characterization of sludges from wastewater treatment plants which are destined to be spread on agricultural lands. Inorganic pollutants are regularly controlled but organic pollutants have received few attention up to now. On this paper, we have been interested on the analysis of the 16 polycyclic aromatic hydrocarbons (PAHs) listed in the US Environmental Protection Agency (US EPA) priority list and more particularly of the six PAHs listed in the European community list (fluoranthene, benzo[b and k]fluoranthene, benzo[a]pyrene, benzo[ghi]perylene, indeno[1,2,3-cd]pyrene). The analysis step consists on liquid chromatography with both fluorescence and UV detections as described in the EPA Method 8310. As for the extraction step, several techniques such as supercritical fluid extraction, pressurized liquid extraction, focused microwave extraction in open vessels, Soxhlet and ultrasonic extractions are compared after optimization of the experimental conditions (solvent nature and quantity, temperature, pressure, duration, ... ) and validation with certified sludges. When optimized, these five extraction techniques are as much efficient with similar relative standard deviation. Whatever the extraction techniques used, the whole analysis protocol permits to quantify PAHs in the range of 0.09 to 0.9 mg/kg of dried sludges.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Compuestos Policíclicos/análisis , Aguas del Alcantarillado/química , Espectrometría de Fluorescencia/métodos , Espectrofotometría Ultravioleta/métodos , Estándares de Referencia
5.
J Chromatogr A ; 823(1-2): 219-30, 1998 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-9818404

RESUMEN

There is a need for a better characterization of sludges from wastewater treatment plants which are destined to be spread on agricultural land. Inorganic pollutants are regularly controlled, but organic pollutants have received little attention up to now. The main problem for trace analysis of organic pollutants comes from the complexity of the various matrices of sludges, which depends on their origins. Therefore, methods described for soils and sediments cannot be directly applied to sludges which contain high amount of lipids. This paper provides a method for trace-determination of polycyclic aromatic hydrocarbons in the range of mg/kg of dried sludge including an extraction step, and an analysis step by liquid chromatography with fluorescence detection for sensitive quantification and UV-diode-array detection for confirmation. The extraction step was optimized by a selection of the solvent used for both Soxhlet and supercritical-fluid extraction and by setting the experimental conditions (temperature, pressure, modifier, etc.) used for SFE. Extraction recoveries were found similar and quantitative for the two procedures. However supercritical-fluid extraction appears to be a good alternative to Soxhlet extraction because of the consumption of less time and solvent. Detection limits were obtained in the range of 0.1-1 mg/kg of dried sludges, with possible confirmation by UV spectra. The whole method (extraction/quantification/confirmation) was validated using sludges which have been certified by the Community Bureau of Reference from Brussels (CRM No. 088). Application to the determination of PAHs in urban sludges is presented.


Asunto(s)
Cromatografía Liquida/métodos , Hidrocarburos Policíclicos Aromáticos/análisis , Aguas del Alcantarillado/química , Solventes , Ciclohexanos , Cloruro de Metileno , Espectrometría de Fluorescencia , Espectrofotometría Ultravioleta , Tolueno
6.
J Chromatogr A ; 795(1): 27-42, 1998 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-9503634

RESUMEN

The parameters governing solid-phase microextraction (SPME) are investigated, with emphasis on the determination of the partition coefficients, K, and their use to predict the selection of a fibre, depending on the respective characteristics of the fibres and the analytes. Film thickness and stability of the compounds can interfere with the determination of K values. The time profile curves were determined for twelve pesticides having a wide range of water solubilities and polarities and using four fibres (polydimethylsiloxane, polydimethylsiloxane-divinylbenzene, Carbowax-divinylbenzene and polyacrylate). Although the affinity order was different for the four coatings, no correlation was found between the respective characteristics of the fibres and solutes. The two fibres containing divinylbenzene were shown to have the highest affinities and the polydimethylsiloxane had the lowest affinity. The polyacrylate fibre which is the more polar commercial fibre did not provide the highest affinities for the more polar and water-soluble analytes. The important parameters for quantitative analysis have been evaluated. The calibration curves were similar when one analyte of interest was present on its own in a drinking water sample, or when eleven other pesticides were present at the same concentration or when much higher concentrations of other analytes were present in the sample. Linearity was obtained over a wide range of concentrations in drinking water samples. Detection limits are in agreement with European regulatory levels in drinking water for most of the analytes using solid-phase microextraction-gas chromatography-nitrogen-phosphorus detection (SPME-GC-NPD). In contaminated surface water samples, the chromatograms are relatively clean and most of the compounds can be detected at levels lower than 0.5 microgram/l.


Asunto(s)
Cromatografía de Gases/métodos , Residuos de Plaguicidas/química , Plaguicidas/química , Contaminación Química del Agua/análisis , Abastecimiento de Agua/análisis , Calibración , Modelos Lineales , Concentración Osmolar , Residuos de Plaguicidas/análisis , Plaguicidas/análisis , Plaguicidas/clasificación , Sensibilidad y Especificidad , Factores de Tiempo , Abastecimiento de Agua/normas
7.
J Chromatogr A ; 859(1): 29-39, 1999 Oct 22.
Artículo en Inglés | MEDLINE | ID: mdl-10563413

RESUMEN

A selective clean-up procedure using immunoaffinity solid-phase extraction was applied for the trace-level determination of polycyclic aromatic hydrocarbons (PAHs) in urban waste water and sewage sludges used for soil amendment. Anti-pyrene antibodies have been immobilized on a silica-based sorbent and the cross-reactivity of the antibodies towards structurally related compounds were allowed to extract the whole class of priority PAHs. The selectivity of the antibodies provided clean extracts from sludges and, therefore, the identification and quantification were shown to be easier using either liquid chromatography (LC) with UV diode array and fluorescence detection in series or gas chromatography-mass spectrometry (GC-MS), although some loss of up to 50% was observed for the clean-up. The identification of the PAHs by matching of UV and MS spectra was greatly improved. The procedure, including immunoclean-up and LC coupled to diode array and fluorescence detection, was validated using certified reference materials with native PAHs of concentrations in the range of 0.57-2.16 mg/kg (dry sludges).


Asunto(s)
Cromatografía de Gases/métodos , Cromatografía Liquida/métodos , Compuestos Policíclicos/análisis , Aguas del Alcantarillado/química , Contaminantes Químicos del Agua/análisis , Monitoreo del Ambiente/métodos , Reproducibilidad de los Resultados , Espectrometría de Fluorescencia , Espectrofotometría Ultravioleta
8.
Bull Cancer ; 77(8): 811-20, 1990.
Artículo en Francés | MEDLINE | ID: mdl-2207370

RESUMEN

We report a prospective study concerning the association of surgery-chemotherapy and radiotherapy in the treatment of primary high grade digestive non-Hodgkin's lymphomas in 19 patients. The analysis of 11 stages IE, 5 stages II1E and 3 stages II2E allowed us to evaluate the efficacy and the tolerance of this triple therapeutic association. Fifteen patients are alive and well with a median follow-up of 54 months. One of these patients relapsed, but after autologous bone marrow transplantation is in second unmaintained complete remission. Four patients died of intercurrent aetiology although one death was related to treatment morbidity. Our results and the analysis of literature data lead us to recommend the triple association in the treatment of stage II2E high grade primary digestive lymphomas (PDL) and for PDL without complete resection. However, surgery and chemotherapy appear to be sufficient in the treatment of stages IE and II1E with complete resection.


Asunto(s)
Terapia Combinada , Neoplasias del Sistema Digestivo/terapia , Linfoma no Hodgkin/terapia , Adulto , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Trasplante de Médula Ósea , Neoplasias del Sistema Digestivo/patología , Femenino , Humanos , Linfoma no Hodgkin/patología , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Pronóstico , Estudios Prospectivos
9.
Presse Med ; 28(6): 277-8, 1999 Feb 13.
Artículo en Francés | MEDLINE | ID: mdl-10073168

RESUMEN

BACKGROUND: Coeliac disease is known to favor the development of neoplasia. Coeliac disease associated with small-cell carcinoma of the esophagus has not been reported to date. CASE REPORT: A 51-year-old man with coeliac disease known for several years was hospitalized for epigastric pain. Work-up led to the diagnosis of small-cell carcinoma of the lower esophagus. The patient was treated with 6 cycles of chemotherapy using an etoposide-ciplatinum protocol associated with 60 Gy radiotherapy starting at the third cycle. The patient has remained in complete remission 2 years after diagnosis. DISCUSSION: Small-cell carcinoma of the esophagus is an exceptional finding in a patient with coeliac disease. Chemotherapy associated with radiotherapy has been successful in our patient.


Asunto(s)
Carcinoma de Células Pequeñas/etiología , Enfermedad Celíaca/complicaciones , Neoplasias Esofágicas/etiología , Protocolos de Quimioterapia Combinada Antineoplásica , Carcinoma de Células Pequeñas/tratamiento farmacológico , Carcinoma de Células Pequeñas/radioterapia , Cisplatino/uso terapéutico , Protocolos Clínicos , Neoplasias Esofágicas/tratamiento farmacológico , Neoplasias Esofágicas/radioterapia , Etopósido/uso terapéutico , Humanos , Masculino , Persona de Mediana Edad , Inducción de Remisión
10.
Presse Med ; 30(4): 163-5, 2001 Feb 03.
Artículo en Francés | MEDLINE | ID: mdl-11229304

RESUMEN

BACKGROUND: Extranodal involvement is not unusual in mantle cell lymphoma (MCL) which accounts for 6% of non-Hodgkin's lymphomas. Simultaneous localization in the eyelid and in the breast, as observed in our case, is however exceptional. CASE REPORT: Chronic lymphoid leukemia (CLL) was suspected in a 71-year-old woman with asthenia, a cervical and axillary nodal enlargement and elevated lymphocyte count. Blood immunoflow cytometry analysis, occurrence of rapidly growing tumors involving the two breasts and eyelids and cytogenetic and molecular features led to the diagnosis of MCL. A very good partial remission was obtained with second-line polychemotherapy composed of cytarabin, cisplatin and dexamethasone, but lasted only 3 months after the end of 6 cycles. DISCUSSION: Primary breast and eyelid lymphomas are rare. Such localizations are exceptional in MCL and are signs of aggressive disease. Before extra-nodal involvement, MCL may simulate banal CLL. Therefore, systematic immunohistochemistry and if necessary molecular analysis are useful for early diagnosis of MCL. Prognosis is particularly poor. Conventional chemotherapy cannot provide cure of MCL and median survival is 48 months. For this reason, high-dose chemotherapy with stem cell graft has to be discussed in young patients. MCL is currently characterized by Bcl1 rearrangement, t(11-14) translocation and cyclin D1 overexpression among small B-cell lymphomas in recent REAL- and WHO-classifications.


Asunto(s)
Neoplasias de la Mama/patología , Neoplasias de los Párpados/patología , Linfoma de Células del Manto/patología , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/terapia , Terapia Combinada , Neoplasias de los Párpados/diagnóstico , Neoplasias de los Párpados/terapia , Femenino , Trasplante de Células Madre Hematopoyéticas , Humanos , Inmunohistoquímica , Linfoma de Células del Manto/diagnóstico , Linfoma de Células del Manto/terapia , Pronóstico
13.
Eur J Haematol ; 66(1): 11-7, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11168502

RESUMEN

Few studies have been performed regarding multiple myeloma (MM) in elderly patients. We report a retrospective series of 130 unselected patients with MM aged 75 yr or more at diagnosis. Presenting features were identical to those reported in younger patients, except for a higher rate of infection. Heavy comorbidity was characteristic of unselected geriatric patients. Ninety-four patients received conventional chemotherapy. The response rate was 62%. Treatment toxicity was mild. Median survival was 22 months. Durie-Salmon (DS) clinical stages II and III MM were severe and often led to death, while significantly more patients with DS stage I MM died from unrelated causes (p<0.0001). Univariate analysis showed that age > or = 85 yr, performance status > or = 2, creatinine level > or = 120 micromol/l, beta 2 microglobulin level > 4 mg/l, C-reactive protein level > 6 mg/l, platelet count < 100 x 10(9)/l, presence of infection and lack of response to chemotherapy were adverse prognostic factors for survival. In Cox multivariate regression analysis, age > or = 85 yr (p<0.0001), performance status > or = 2 (p<0.0001) and creatinine level > or = 120 micromol/l (p<0.0001) were independent factors in predicting short survival. This study provides evidence that in patients with symptomatic MM age should not be considered as a major obstacle to active treatment. Prospective clinical trials are needed in this population of patients and should include an assessment of quality of life.


Asunto(s)
Mieloma Múltiple/epidemiología , Anciano , Anciano de 80 o más Años , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Causas de Muerte , Comorbilidad , Ciclofosfamida/administración & dosificación , Dexametasona/administración & dosificación , Doxorrubicina/administración & dosificación , Etopósido/administración & dosificación , Femenino , Francia/epidemiología , Humanos , Interferón-alfa/administración & dosificación , Tablas de Vida , Lomustina/administración & dosificación , Masculino , Melfalán/administración & dosificación , Mieloma Múltiple/sangre , Mieloma Múltiple/diagnóstico , Mieloma Múltiple/tratamiento farmacológico , Mieloma Múltiple/patología , Proteínas de Mieloma/análisis , Estadificación de Neoplasias , Síndromes Paraneoplásicos/epidemiología , Prednimustina/administración & dosificación , Prednisona/administración & dosificación , Pronóstico , Modelos de Riesgos Proporcionales , Estudios Retrospectivos , Análisis de Supervivencia , Resultado del Tratamiento , Vincristina/administración & dosificación
14.
Ann Oncol ; 8 Suppl 1: 49-52, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9187429

RESUMEN

BACKGROUND: The International Prognostic Index (IPI) is widely used to predict outcome of patients with aggressive lymphomas. Our goal was to assess the prognostic value of this index for low-grade lymphoma. PATIENTS AND METHODS: One hundred eighty-two patients with disseminated (stage III or IV) low-grade lymphoma were enrolled in a prospective multicenter trial. According to the initial features, treatment either was started immediately or was deferred until indicated by disease progression. Patients received the same polychemotherapy regimen, given monthly for six cycles. They were assigned to one of four risk groups according to the number of presenting risk factors: low-risk (0 or 1), low-intermediate-risk (2), high-intermediate-risk (3), high-risk groups (4). RESULTS: Survival curves (Kaplan-Meier method) demonstrated a high significant difference for the four groups (log-rank: P < 0.0001). Median survival for the low-risk group has yet to be reached, while that for the three other groups are, respectively, 65, 34, and 12 months. CONCLUSIONS: In this study, the IPI has been found to be an important prognostic tool in low-grade lymphoma and may be used in the selection of appropriate therapeutic approaches for individual patients.


Asunto(s)
Linfoma no Hodgkin/mortalidad , Linfoma no Hodgkin/patología , Índice de Severidad de la Enfermedad , Humanos , L-Lactato Deshidrogenasa/sangre , Linfoma no Hodgkin/terapia , Persona de Mediana Edad , Estadificación de Neoplasias , Valor Predictivo de las Pruebas , Pronóstico , Estudios Prospectivos , Análisis de Supervivencia , Resultado del Tratamiento
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