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1.
Phys Rev Lett ; 130(22): 226401, 2023 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-37327408

RESUMEN

Using angle-resolved photoemission spectroscopy, combined with first principle and coupled self-consistent Poisson-Schrödinger calculations, we demonstrate that potassium (K) atoms adsorbed on the low-temperature phase of 1T-TiSe_{2} induce the creation of a two-dimensional electron gas (2DEG) and quantum confinement of its charge-density wave (CDW) at the surface. By further changing the K coverage, we tune the carrier density within the 2DEG that allows us to nullify, at the surface, the electronic energy gain due to exciton condensation in the CDW phase while preserving a long-range structural order. Our Letter constitutes a prime example of a controlled exciton-related many-body quantum state in reduced dimensionality by alkali-metal dosing.


Asunto(s)
Frío , Electrones , Espectroscopía de Fotoelectrones
2.
Blood ; 130(11): 1315-1326, 2017 09 14.
Artículo en Inglés | MEDLINE | ID: mdl-28701367

RESUMEN

Dose-dense induction and up-front consolidation with autologous stem cell transplantation (ASCT) remain controversial issues when treating patients with high-risk diffuse large B-cell lymphoma. GELA designed a randomized phase 2 trial evaluating the efficacy of either rituximab, doxorubicin, cyclophosphamide, vindesine, bleomycin, prednisone (R-ACVBP) or rituximab, cyclophosphamide, doxorubicin, vincristine, prednisone (R-CHOP14) induction and a positron emission tomography (PET)-driven ASCT or standard immunochemotherapy (SIC) consolidation in age-adjusted international prognosis index 2 (aaIPI2)-aaIPI3 patients. PET was performed at baseline, after 2 (PET2) and 4 (PET4) induction cycles, and centrally assessed using international harmonization project (IHP) criteria. PET2-/PET4- patients were assigned SIC, PET2+/PET4- patients were assigned ASCT, and PET4+ patients were treated with the investigator's choice. The primary end-point was the 2007 international working group complete response (CR) rate after induction. Change in maximum standard uptake value (ΔSUVmax) after PET assessment was explored. Two hundred eleven patients were randomly assigned to R-ACVBP (n = 109) or R-CHOP14 (n = 102). PET4-/CR rates were 53%/47% with R-ACVBP and 41%/39% with R-CHOP14 (CR 95% confidence interval [CI], 38%-67% and 28%-54%, respectively; P = .076). Consolidation in the R-ACVBP and R-CHOP14 groups was SIC in 26% and 23% of patients and ASCT in 28% and 18% of patients, respectively. PET4 positivity was higher with R-CHOP14 vs R-ACVBP (54% vs 41%; P = .08), leading to more salvage therapy (37% vs 26%; P = .07) and lower event-free survival (EFS; 4-year EFS, 31% vs 43%; P < .01), but progression-free survival (PFS) and overall survival (OS) were similar in both groups. PET2-/PET4- and PET2+/PET4- patients had similar outcomes. Using ΔSUVmax, 79% of the patients were PET2-/PET4- ΔSUVmaxPET0-4 >70% was associated with better outcome (4-year PFS, 84% vs 35%; 4-year OS, 91% vs 57%; P < .0001), whatever the consolidation. Superiority of R-ACVBP over R-CHOP14 was not established, as IHP criteria did not properly reflect disease control. ΔSUVmax may help better select patients needing an alternative to SIC, including ASCT.


Asunto(s)
Quimioterapia de Consolidación , Fluorodesoxiglucosa F18/química , Linfoma de Células B Grandes Difuso/tratamiento farmacológico , Tomografía de Emisión de Positrones , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Determinación de Punto Final , Femenino , Trasplante de Células Madre Hematopoyéticas , Humanos , Linfoma de Células B Grandes Difuso/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Resultado del Tratamiento , Adulto Joven
3.
Phys Rev Lett ; 111(2): 027601, 2013 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-23889444

RESUMEN

By combining x-ray excited Auger electron diffraction experiments and multiple scattering calculations we reveal a layer-resolved shift for the Mg KL23L23 Auger transition in MgO ultrathin films (4-6 Å) on Ag(001). This resolution is exploited to demonstrate the possibility of controlling Mg atom incorporation at the MgO/Ag(001) interface by exposing the MgO films to a Mg flux. A substantial reduction of the MgO/Ag(001) work function is observed during the exposition phase and reflects both band-offset variations at the interface and band bending effects in the oxide film.

4.
Med Mal Infect ; 41(12): 652-6, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22056376

RESUMEN

BACKGROUND: Adult leukemia patients with febrile neutropenia have a higher volume of distribution requiring increased drug doses. We performed a survey of vancomycin use in that population to assess the accuracy of our dosing guidelines. METHODS: We retrospectively reviewed the charts and laboratory results of vancomycin prescription and monitoring in adult acute myeloid leukemia patients with febrile neutropenia in a teaching hospital. RESULTS: Fifty-four patients received 67 vancomycin courses between January 2005 and April 2007. A loading dose was used in 97% of cases dosed at a mean 15.5±3.3mg/kg. It was followed by a continuous infusion of an average 35.4±6.9mg/kg per day maintenance dose. Serum monitoring yielded serum levels above the 20mg/L target in only 12% of cases. Despite higher dose, the target concentration was only reached in 32% of cases, after a mean 1.5 dose adjustment. The mean final maintenance dose was 42.1±9.4mg/kg per day. Vancomycin was well tolerated and induced only two temporary increases in serum creatinine. The treatment was microbiologically justified in only two cases. The mean length of therapy was 7.7±4.4 days and 41 over 65 (63%) non-documented infections were treated for more than five days despite local guidelines recommending a maximum 5-day course without bacterial documentation. Overall, only seven (10%) vancomycin courses complied with all defined criteria. CONCLUSIONS: Vancomycin use was not optimal. We updated our guidelines after the study to dramatically reduce vancomycin indications in leukemia patients. When it is indicated, following the loading dose, we more closely monitor vancomycin serum levels to allow for an earlier dose adjustment when necessary.


Asunto(s)
Antibacterianos/sangre , Infecciones Bacterianas/sangre , Fiebre/etiología , Leucemia Mieloide/sangre , Neutropenia/complicaciones , Vancomicina/sangre , Enfermedad Aguda , Antibacterianos/administración & dosificación , Antibacterianos/efectos adversos , Antibacterianos/farmacocinética , Antibacterianos/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Infecciones Bacterianas/tratamiento farmacológico , Infecciones Bacterianas/etiología , Creatinina/sangre , Relación Dosis-Respuesta a Droga , Monitoreo de Drogas , Adhesión a Directriz , Hospitales Universitarios/estadística & datos numéricos , Humanos , Prescripción Inadecuada , Quimioterapia de Inducción/efectos adversos , Infusiones Intravenosas , Enfermedades Renales/sangre , Enfermedades Renales/inducido químicamente , Leucemia Mieloide/complicaciones , Leucemia Mieloide/inmunología , Guías de Práctica Clínica como Asunto , Estudios Retrospectivos , Infecciones Estafilocócicas/sangre , Infecciones Estafilocócicas/tratamiento farmacológico , Infecciones Estafilocócicas/etiología , Infecciones Estafilocócicas/prevención & control , Vancomicina/administración & dosificación , Vancomicina/efectos adversos , Vancomicina/farmacocinética , Vancomicina/uso terapéutico
5.
Leuk Lymphoma ; 48(2): 321-9, 2007 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17325892

RESUMEN

We analyzed the outcome of 25 consecutive patients with chronic hematological malignancy who underwent allogeneic stem-cell transplantation conditioned with fludarabine (30 mg/m2/day, thrice) and total body irradiation (2 Gy). All patients received peripheral blood stem cells from an HLA-identical sibling donor. With a median follow-up of 769 days (range, 244 - 1231), the estimated 2-year overall survival (OS), event-free survival (EFS), transplantation-related mortality and relapse rates were 53%, 45%, 27%, and 39%, respectively. All patients had initial engraftment. Acute Grade II - IV graft-versus-host disease (GVHD) was recorded in 14 patients (56%), including 7 (28%) with Grade III - IV GVHD. Sixteen of the 23 patients (70%) who survived more than 100 days developed chronic GVHD. OS and EFS were adversely influenced by acute Grade III - IV GVHD (p < 0.001 and p = 0.033, respectively), but chronic GVHD seemed to favorably influence these two parameters (p = 0.03 and p < 0.001, respectively). Patients with full-donor chimerism at day 30 had lower relapse rates, as did those who received high-dose allogeneic CD8+ lymphocytes with their graft (p = 0.026). Collectively, these results provide a framework for refining nonmyeloablative conditioning, to improve outcome with an acceptable risk of GVHD.


Asunto(s)
Antineoplásicos/uso terapéutico , Neoplasias Hematológicas/terapia , Trasplante de Células Madre Hematopoyéticas , Acondicionamiento Pretrasplante , Vidarabina/análogos & derivados , Irradiación Corporal Total , Adulto , Terapia Combinada , ADN (Citosina-5-)-Metiltransferasas/antagonistas & inhibidores , Femenino , Enfermedad Injerto contra Huésped/terapia , Células Madre Hematopoyéticas/efectos de los fármacos , Humanos , Inmunosupresores/uso terapéutico , Masculino , Persona de Mediana Edad , Tasa de Supervivencia , Quimera por Trasplante , Trasplante Homólogo , Vidarabina/uso terapéutico
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