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1.
Breast Cancer Res Treat ; 192(3): 603-610, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35150367

RESUMEN

BACKGROUND: We aimed at investigating outcome of systemic treatments in advanced breast PT. METHODS: All cases of advanced breast PT treated with systemic treatments from 1999 to 2019, in one of the referral sarcoma centers involved in the study, were retrospectively reviewed. RESULTS: 56 female patients were identified. Median age was 52 (range of 25-76) years. Patients received a median number of 2 systemic treatments (range of 1-4). Best responses according to RECIST were 1 (3.7%) CR, 11 (40.7%) PR, 6 (22.2%) SD, 9 (33.3%) PD with anthracyclines plus ifosfamide (AI); 2 (16.7%) PR, 4 (33.3%) SD, 6 (50.0%) PD with anthracycline alone; 3 (18.8%) PR, 4 (25.0%) SD, 9 (56.3%) PD with high-dose ifosfamide given as a continuous infusion (HD-IFX); 3 (20.0%) SD, 12 (80.0%) PD with a gemcitabine-based regimen (with 2 patients not evaluable); 1 (8.3%) PR, 2 (16.7%) SD, 9 (75.0%) PD with trabectedin (with 1 patient not evaluable); 1 (16.7%) PR, 1 (16.7%) SD, 4 (66.7%) PD with tyrosine-kinase inhibitors (TKI). The median PFS were 5.7 (IQR 2.5-9.1) months with AI; 3.2 (IQR 2.2-5.0) months with anthracycline alone; 3.4 (IQR 1.4-6.7) months with HD-IFX; 2.1 (IQR 1.4-5.2) months with gemcitabine-based chemotherapy; 1.8 (IQR 0.7-6.6) months with trabectedin; 3.4 (IQR 3.1-3.8) months with TKI. With a median follow-up of 35.3 (IQR 17.6-66.9) months, OS from the start of first-line systemic treatment was 15.2 (IQR 7.6-39.6) months. CONCLUSION: In this series of advanced PT (to our knowledge, the largest reported so far), AI was associated with a high rate of responses, however, with a median PFS of 5.7 months. Other systemic treatments were poorly active.


Asunto(s)
Neoplasias de la Mama , Sarcoma , Adulto , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Neoplasias de la Mama/tratamiento farmacológico , Femenino , Humanos , Persona de Mediana Edad , Criterios de Evaluación de Respuesta en Tumores Sólidos , Estudios Retrospectivos , Sarcoma/patología
2.
Ann Oncol ; 32(4): 533-541, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33482247

RESUMEN

BACKGROUND: In 2004, we started an intergroup randomized trial of adjuvant imatinib versus no further therapy after R0-R1 surgery in localized, high/intermediate-risk gastrointestinal stromal tumors (GIST) patients. Interim analysis results were published in 2015 upon recommendation from an independent data review committee. We report the final outcome of the study. PATIENTS AND METHODS: This was a randomized, open-label, multicenter phase III trial carried out at 112 hospitals in 12 countries. Patients were randomized to 2 years of imatinib, 400 mg daily, or no further therapy after surgery. The primary endpoint was imatinib failure-free survival (IFFS), while relapse-free survival (RFS), relapse-free interval (RFI), overall survival (OS) and toxicity were secondary endpoints. Adjusting for the interim analyses, results on IFFS were assessed on a 4.3% significance level; for the other endpoints, 5% was used. RESULTS: Nine hundred and eight patients were randomized between January 2005 and October 2008: 454 to imatinib and 454 to observation; 835 patients were eligible. With a median follow-up of 9.1 years, 5 (10)-year IFFS was 87% (75%) in the imatinib arm versus 83% (74%) in the control arm [hazard ratio (HR) = 0.87, 95.7% confidence interval (CI) (0.65; 1.15), P = 0.31]; RFS was 70% versus 63% at 5 years and 63% versus 61% at 10 years, [HR = 0.71, 95% CI (0.57; 0.89), P = 0.002]; OS was 93% versus 92% at 5 years and 80% versus 78% at 10 years [HR = 0.88, 95% CI (0.65; 1.21), P = 0.43]. Among 526 patients with high-risk GIST by local pathology, 10-year IFFS and RFS were 69% versus 61%, and 48% versus 43%, respectively. CONCLUSIONS: With 9.1 years of follow-up, a trend toward better long-term IFFS in imatinib-treated patients was observed in the high-risk subgroup. Although the difference was not statistically significant and the surrogacy value of such an endpoint is not validated, this may be seen as supporting the results reported by the Scandinavian/German trial, showing a sustained small but significant long-term OS benefit in high-risk GIST patients treated with 3 years of adjuvant imatinib.


Asunto(s)
Antineoplásicos , Neoplasias Gastrointestinales , Tumores del Estroma Gastrointestinal , Sarcoma , Antineoplásicos/uso terapéutico , Quimioterapia Adyuvante , Neoplasias Gastrointestinales/tratamiento farmacológico , Tumores del Estroma Gastrointestinal/tratamiento farmacológico , Humanos , Mesilato de Imatinib/uso terapéutico , Italia , Recurrencia Local de Neoplasia/tratamiento farmacológico , Sarcoma/tratamiento farmacológico
3.
J Neuroradiol ; 47(1): 59-61, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30448427

RESUMEN

Ischemic stroke is the most common neurological complication of cardiac catheterization resulting in a high morbidity and mortality. We present a 44-year-old man admitted for vasospastic angina that suffered a right middle cerebral artery (MCA) occlusion after a cardiac catheterization. Mechanical thrombectomy was indicated and complete arterial recanalization was achieved. The material obtained showed a fragment of a healthy artery. Partial radial endarterectomy and cerebral embolization may be a rare complication of cardiac catheterization.


Asunto(s)
Cateterismo Cardíaco/efectos adversos , Embolización Terapéutica/métodos , Infarto de la Arteria Cerebral Media/etiología , Infarto de la Arteria Cerebral Media/cirugía , Complicaciones Posoperatorias , Adulto , Isquemia Encefálica/diagnóstico por imagen , Isquemia Encefálica/etiología , Humanos , Infarto de la Arteria Cerebral Media/diagnóstico por imagen , Masculino , Accidente Cerebrovascular/diagnóstico por imagen , Accidente Cerebrovascular/etiología
5.
Br J Cancer ; 117(6): 767-774, 2017 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-28787430

RESUMEN

BACKGROUND: First Spanish trial of Ewing sarcoma (ES) including adults and children with the aim to test the efficacy of Gemcitabine and Docetaxel (G/D) in newly diagnosed high-risk (HR) patients. METHODS: This was a prospective, multicentric, non-randomised, open study for patients ⩽40 years with newly diagnosed ES. HR patients (metastatic, axial-pelvic primaries or bone marrow micrometastasis) received 2 window cycles of G/D. Patients with an objective response (OR) to G/D received 12 monthly cycles of G/D after completion of mP6. The primary end point was the OR rate to the G/D window phase and the event-free survival (EFS) and overall survival (OS) for all patients. The study is registered at ClinicalTrials.gov (identifier: NCT00006734). RESULTS: Forty-three patients were enroled, median age 17 years (range, 3-40). After a median follow-up of 43.4 months, the 5-year OS rate is 55.0% (95% CI, 41-74%) with an EFS of 50.0% (95% CI, 36-68%). The 5-year OS and EFS rates for standard risk (SR) patients was 76.0% (95% CI, 57-100%) and 71.0% (CI, 54-94%); for HR 36.0% (CI, 20-65%) and 29.0% (CI, 15-56%). Twelve of 17 (70.6%) high-risk (HR) patients showed an OR (7 PR and 5 SD) to G/D window therapy. The 5-year OS rate for patients ⩽18 years of age was 74.0% (CI, 56-97%) and 31.0% for >18 years (95% CI, 15-66%), P<0.001. Grade 4 adverse events during mP6 occurred in 28/39 of patients (72%) and did not correlate with age. Multivariate survival analyses with <18 vs ⩾18 and risk groups significant differences, P<0.00001. Using a Cox model for OS, both age and risk group were statistically significant (P=0.0011 and P=0.0065, respectively). CONCLUSIONS: Age at diagnosis is an independent prognostic factor superior to the presence of metastases with 18 years as the strongest cut-off. The mP6 regimen provided survival curves that plateau at 3 years and G/D produced significant responses in HR-ES that is worth further exploring.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias Óseas/tratamiento farmacológico , Sarcoma de Ewing/tratamiento farmacológico , Adolescente , Adulto , Factores de Edad , Niño , Preescolar , Desoxicitidina/administración & dosificación , Desoxicitidina/análogos & derivados , Supervivencia sin Enfermedad , Docetaxel , Humanos , Estimación de Kaplan-Meier , Oportunidad Relativa , Pronóstico , Estudios Prospectivos , Sarcoma de Ewing/mortalidad , España , Tasa de Supervivencia , Taxoides/administración & dosificación , Gemcitabina
6.
Ann Oncol ; 28(6): 1230-1242, 2017 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-28184416

RESUMEN

Chordomas are rare, malignant bone tumors of the skull-base and axial skeleton. Until recently, there was no consensus among experts regarding appropriate clinical management of chordoma, resulting in inconsistent care and suboptimal outcomes for many patients. To address this shortcoming, the European Society of Medical Oncology (ESMO) and the Chordoma Foundation, the global chordoma patient advocacy group, convened a multi-disciplinary group of chordoma specialists to define by consensus evidence-based best practices for the optimal approach to chordoma. In January 2015, the first recommendations of this group were published, covering the management of primary and metastatic chordomas. Additional evidence and further discussion were needed to develop recommendations about the management of local-regional failures. Thus, ESMO and CF convened a second consensus group meeting in November 2015 to address the treatment of locally relapsed chordoma. This meeting involved over 60 specialists from Europe, the United States and Japan with expertise in treatment of patients with chordoma. The consensus achieved during that meeting is the subject of the present publication and complements the recommendations of the first position paper.


Asunto(s)
Cordoma/terapia , Guías de Práctica Clínica como Asunto , Humanos , Recurrencia Local de Neoplasia
7.
Ann Oncol ; 28(12): 2994-2999, 2017 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-29045512

RESUMEN

BACKGROUND: Patients with relapsed unresectable osteosarcoma represents an unmet need, so active and safe systemic treatments are required. Fas cell surface death receptor and mammalian target of rapamycin pathways are implicated in progressing osteosarcoma, and we had preclinical and clinical experience with a scheme that targets both pathways. Therefore, we designed a phase II trial with gemcitabine plus rapamycin, to determine the efficacy and safety, in this subset of patients. PATIENTS AND METHODS: A multicenter, single-arm phase II trial was sponsored by the Spanish Group for Research on Sarcoma. Osteosarcoma patients, relapsed or progressing after standard chemotherapy and unsuitable for metastasectomy received gemcitabine and rapamycin p.o. 5 mg/day except for the same day of gemcitabine administration, and the day before. The main end point was 4-month progression-free survival rate (PFSR), with the assumption that rates higher than 40% would be considered as an active regimen. Translational research aimed to correlate biomarkers with the clinical outcome. RESULTS: Thirty-five patients were enrolled and received at least one cycle. PFSR at 4 months was 44%, and after central radiologic assessment, 2 partial responses and 14 stabilizations (48.5%) were reported from 33 assessable patients. The most frequent grade 3-4 adverse events were: neutropenia (37%), thrombocytopenia (20%), anemia (23%), and fatigue (15%); however, only three patients had febrile neutropenia. Positive protein expression of RRM1 significantly correlated with worse PFS and overall survival, while positivity of P-ERK1/2 was correlated with significant better overall survival. CONCLUSION: Gemcitabine plus sirolimus exhibits satisfactory antitumor activity and safety in this osteosarcoma population, exceeding the prespecified 40% of 4-month PFSR. The significant correlation of biomarkers with clinical outcome encourages further prospective investigation.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias Óseas/tratamiento farmacológico , Osteosarcoma/tratamiento farmacológico , Adolescente , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Neoplasias Óseas/patología , Niño , Preescolar , Desoxicitidina/administración & dosificación , Desoxicitidina/efectos adversos , Desoxicitidina/análogos & derivados , Progresión de la Enfermedad , Supervivencia sin Enfermedad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Osteosarcoma/patología , Recurrencia , Sirolimus/administración & dosificación , Sirolimus/efectos adversos , Adulto Joven , Gemcitabina
9.
Ann Oncol ; 27(12): 2283-2288, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27733375

RESUMEN

BACKGROUND: To report on long-term results of a phase 3 trial comparing three versus five cycles of adjuvant chemotherapy (CT) with full-dose epirubicin+ifosfamide in high-risk soft tissue sarcomas (STS). METHODS: Patients (pts) were randomized to receive three preoperative cycles of epirubicin 120 mg/m2 and ifosfamide 9 g/m2 (Arm A) or to receive the same three preoperative cycles plus two postoperative cycles (Arm B). Radiotherapy could be either delivered in the preoperative or in the postoperative setting. Non-inferiority of the primary end point, OS, was assessed by the confidence interval of the hazard ratio (HR; Arm A/Arm B) derived from Cox model. RESULTS: Between January 2002 and April 2007, 164 pts were assigned to arm A and 164 to arm B. At a median follow-up (FU) of 117 months (IQ range 103-135 months), 123 deaths were recorded: 58 in Arm A and 65 in Arm B. Ten-year OS was 61% for the entire group of patients: 64% in Arm A and 59% in Arm B. The intention-to-treat analysis confirmed that three cycles were not inferior to five cycles (one-sided 95% upper confidence limit was 1.24). A per protocol analysis was consistent with these results. Pts with leiomyosarcoma and undifferentiated pleomorphic sarcoma (UPS) had the lowest, and the highest response rates, respectively. Consistently, Leiomyosarcoma and UPS had the worse and the best prognosis, respectively. CONCLUSIONS: At a longer FU, the non-inferiority of three cycles of a full-dose conventional CT in comparison to five is confirmed. Response to therapy is also confirmed to be associated with better survival. This regimen is currently tested within an ongoing international trial against three cycles of a neoadjuvant histology-tailored CT (ClinicalTrials.gov Identifier: NCT01710176).


Asunto(s)
Quimioterapia Adyuvante , Leiomiosarcoma/tratamiento farmacológico , Pronóstico , Sarcoma/tratamiento farmacológico , Adulto , Anciano , Supervivencia sin Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Leiomiosarcoma/patología , Leiomiosarcoma/radioterapia , Masculino , Persona de Mediana Edad , Factores de Riesgo , Sarcoma/patología , Sarcoma/radioterapia , Resultado del Tratamiento
11.
Invest New Drugs ; 32(2): 287-94, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23801301

RESUMEN

BACKGROUND: This phase I trial assessed safety, pharmacokinetics (PK), dose limiting toxicity (DLT), maximum tolerated dose and recommended dose (RD) of the combination of sorafenib plus ifosfamide in patients with advanced sarcoma. METHODS: Twelve sarcoma patients (9 soft-tissue, 3 bone sarcoma) were treated with sorafenib plus ifosfamide (starting doses 200 mg bid and 6 g/m(2) respectively). A 3 + 3 dose escalation design with cohorts of 3-6 patients was used. A study to assess the in vitro efficacy of the combination was also conducted. RESULTS: Three DLTs were observed: fatigue grade 4 with sorafenib 400 mg bid plus ifosfamide 6 g/m(2) and encephalopathy and emesis grade 3 with sorafenib 400 mg bid plus ifosfamide 7.5 g/m(2). Other toxicities included diarrhea, hand-foot syndrome, mucositis, neutropenia, skin rash and thrombocytopenia. There were no relevant effects on PK of sorafenib but an increase in ifosfamide active metabolite 4-hydroxy-ifosfamide was observed. Eight patients achieved stable disease lasting more than 12 weeks. An additive effect was observed in vitro. CONCLUSIONS: RD was sorafenib 400 mg bid plus ifosfamide 6 g/m(2), allowing administration of active doses of both agents. Limited preliminary antitumor activity was also observed. A phase II study is currently ongoing.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Sarcoma/tratamiento farmacológico , Adulto , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Muerte Celular/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Femenino , Humanos , Ifosfamida/administración & dosificación , Ifosfamida/efectos adversos , Ifosfamida/análogos & derivados , Ifosfamida/farmacología , Masculino , Persona de Mediana Edad , Niacinamida/administración & dosificación , Niacinamida/efectos adversos , Niacinamida/análogos & derivados , Niacinamida/farmacología , Compuestos de Fenilurea/administración & dosificación , Compuestos de Fenilurea/efectos adversos , Compuestos de Fenilurea/farmacología , Inhibidores de Proteínas Quinasas/administración & dosificación , Inhibidores de Proteínas Quinasas/efectos adversos , Inhibidores de Proteínas Quinasas/farmacología , Sarcoma/metabolismo , Sorafenib , Adulto Joven , Quinasas raf/antagonistas & inhibidores
12.
Ann Oncol ; 29(Suppl 4): iv51-iv67, 2018 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-29846498
13.
Ann Oncol ; 29(Suppl 4): iv68-iv78, 2018 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-29846513
16.
Ann Oncol ; 29(Suppl 4): iv79-iv95, 2018 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-30285218
17.
ESMO Open ; 8(5): 101618, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37625194

RESUMEN

Synovial sarcoma (SS) is a rare and aggressive disease that accounts for 5%-10% of all soft tissue sarcomas. Although it can occur at any age, it typically affects younger adults and children, with a peak incidence in the fourth decade of life. In >95% of cases, the oncogenic driver is a translocation between chromosomes X and 18 that leads to the formation of the SS18::SSX fusion oncogenes. Early and accurate diagnosis is often a challenge; optimal outcomes are achieved by referral to a specialist center for diagnosis and management by a multidisciplinary team as soon as SS is suspected. Surgery with or without radiotherapy and/or chemotherapy can be effective in localized disease, especially in children. However, the prognosis in the advanced stages is poor, with treatment strategies that have relied heavily on traditional cytotoxic chemotherapies. Therefore, there is an unmet need for novel effective management strategies for advanced disease. An improved understanding of disease pathology and its molecular basis has paved the way for novel targeted agents and immunotherapies that are being investigated in clinical trials. This review provides an overview of the epidemiology and characteristics of SS in children and adults, as well as the patient journey from diagnosis to treatment. Current and future management strategies, focusing particularly on the potential of immunotherapies to improve clinical outcomes, are also summarized.

18.
ESMO Open ; 8(6): 102045, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38016251

RESUMEN

BACKGROUND: Conventional cytotoxic drugs are not effective in alveolar soft-part sarcoma (ASPS). Immune checkpoint (programmed cell death protein 1/programmed death-ligand 1) inhibitors (ICIs) are promising drugs in ASPS. A worldwide registry explored the efficacy of ICI in ASPS. MATERIALS AND METHODS: Data from adult patients diagnosed with ASPS and treated with ICI for advanced disease in expert sarcoma centers from Europe, Australia and North America were retrospectively collected, including demographics and data related to treatments and outcome. RESULTS: Seventy-six ASPS patients, with a median age at diagnosis of 25 years (range 3-61 years), were registered. All patients received ICI for metastatic disease. Immunotherapy regimens consisted of monotherapy in 38 patients (50%) and combination in 38 (50%) (23 with a tyrosine kinase inhibitor). Among the 68 assessable patients, there were 3 complete responses and 34 partial responses, translating into an overall response rate of 54.4%. After a median follow-up of 36 months [95% confidence interval (CI) 32-40 months] since the start of immunotherapy, 45 (59%) patients have progressed on ICI, with a median progression-free survival (PFS) of 16.3 months (95% CI 8-25 months). Receiving ICI in first line (P = 0.042) and achieving an objective response (P = 0.043) correlated with a better PFS. Median estimated overall survival (OS) from ICI initiation has not been reached. The 12-month and 24-month OS rates were 94% and 81%, respectively. CONCLUSIONS: This registry constitutes the largest available series of ASPS treated with ICI. Our results suggest that the ICI treatment provides long-lasting disease control and prolonged OS in patients with advanced ASPS, an ultra-rare entity with limited active therapeutic options.


Asunto(s)
Antineoplásicos , Sarcoma de Parte Blanda Alveolar , Adulto , Humanos , Preescolar , Niño , Adolescente , Adulto Joven , Persona de Mediana Edad , Inhibidores de Puntos de Control Inmunológico/farmacología , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Estudios Retrospectivos , Sarcoma de Parte Blanda Alveolar/tratamiento farmacológico , Sarcoma de Parte Blanda Alveolar/patología , Antineoplásicos/uso terapéutico , Inhibidores de Proteínas Quinasas/uso terapéutico
19.
Ann Oncol ; 23(11): 2776-2781, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22831984

RESUMEN

BACKGROUND: The management of primary gastrointestinal stromal tumours (GISTs) has evolved with the introduction of adjuvant therapy. Recently reported results of the SSG XVIII/AIO trial by the Scandinavian Sarcoma Group (SSG) and the German Working Group on Medical Oncology (AIO) represent a significant change in the evidence for adjuvant therapy duration. The objectives of this European Expert Panel meeting were to describe the optimal management and best practice for the systemic adjuvant treatment of patients with primary GISTs. MATERIALS AND METHODS: A panel of medical oncology experts from European sarcoma research groups were invited to a 1-day workshop. Several questions and discussion points were selected by the organising committee prior to the conference. The experts reviewed the current literature of all clinical trials available on adjuvant therapy for primary GISTs, considered the quality evidence and formulated recommendations for each discussion point. RESULTS: Clinical issues were identified and provisional clinical opinions were formulated for adjuvant treatment patient selection, imatinib dose, duration and patient recall, mutational analysis and follow-up of primary GIST patients. Adjuvant imatinib 400 mg/day for 3 years duration is a standard treatment in all patients with significant risk of recurrence following resection of primary GISTs. Patient selection for adjuvant therapy should be based on any of the three commonly used patient risk stratification schemes. R1 surgery (versus R0) alone is not an indication for adjuvant imatinib in low-risk GIST. Recall and imatinib restart could be proposed in patients who discontinued 1-year adjuvant imatinib within the previous 3 months and may be considered on a case-by-case basis in patients who discontinued within the previous year. Mutational analysis is recommended in all cases of GISTs using centralised laboratories with good quality control. Treatment is not recommended in an imatinib-insensitive D842V-mutated GIST. During adjuvant treatment, patients are recommended to be clinically assessed at 1- to 3-month intervals. Upon discontinuation, computed tomography scan (CT) scans are recommended every 3 to 4 months for 2 years when the risk of relapse is highest, followed by every 6 months until year 5 and annually until year 10 after treatment discontinuation. CONCLUSIONS: Key points in systemic adjuvant treatment and clinical management of primary GISTs as well as open questions were identified during this European Expert Panel meeting on GIST management.


Asunto(s)
Neoplasias Gastrointestinales/tratamiento farmacológico , Tumores del Estroma Gastrointestinal/tratamiento farmacológico , Piperazinas/uso terapéutico , Pirimidinas/uso terapéutico , Benzamidas , Quimioterapia Adyuvante , Humanos , Mesilato de Imatinib , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Tirosina Quinasas/antagonistas & inhibidores , Resultado del Tratamiento
20.
Nanotechnology ; 23(25): 255701, 2012 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-22652540

RESUMEN

Magnetotransport of individual rolled-up Fe(3)Si nanomembranes is investigated in a broad temperature range from 4.2 K up to 300 K in pulsed magnetic fields up to 55 T. The observed magnetoresistance (MR) has the following pronounced features: (i) MR is negative in the investigated intervals of temperature and magnetic field; (ii) its magnitude increases linearly with the magnetic field in a low-field region and reveals a gradual trend to saturation when the magnetic field increases; (iii) the MR effect becomes more pronounced with increasing temperature. These dependences of MR on the magnetic field and temperature are in line with predictions of the spin-disorder model of the spin-flip s-d interaction assisted with creation or annihilation of magnons, which is expected above a certain critical temperature. Comparison of the MR features in rolled-up and planar samples reveals a substantial increase of the critical temperature in the rolled-up tube, which is attributed to a new geometry and internal strain arising in the rolled-up nanomembranes, influencing the electronic and magnetic properties of the material.

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