RESUMO
The present work suggests the use of a mixed water-based electrolyte containing sulfuric and phosphoric acid for both negative and positive electrolytes of a vanadium redox flow battery. Computational and experimental investigations reveal insights on the possible interactions between the vanadium ions in all oxidation states and sulphate, bisulphate, dihydrogen phosphate ions and phosphoric acid. In situ cycling experiments and ion-specific electrochemical impedance measurements confirmed a significant lowering of the charge-transfer resistance for the reduction of V(iii) ions and, consequently, an increase of the voltaic efficiency associated with the negative side of the battery. This increase of performance is attributable to the complexation of this oxidation state by phosphoric acid. So far, mixed acids have mainly been discussed with the focus on V(v) solubility. In this work we rationalize the impact of the mixed acids on the electrochemical efficiency opening new strategies on how to improve the cycling performance with ionic additives.
RESUMO
In the present paper, a novel method to fabricate ordered arrays of Au/NiO/Au nanowires is described, with the aim of filling the gap between the fundamental study of the electrical properties of scattered single nanowires and the engineered fabrication of nanowire arrays. This approach mainly consists of the following steps: (a) electrodeposition of Au/Ni/Au nanowires into an ordered porous anodic aluminum oxide template; (b) mechanical polishing of the sample to expose the gold tips of Au/Ni/Au nanowires to the template surface; (c) in situ annealing of the Au/Ni/Au nanowires without removing the template. The resulting structure consists in an ordered array of Au/NiO/Au nanowires slightly protruding out of a flat aluminum oxide template. Unlike current approaches, with the described method it is not necessary to remove the template in order to oxidize the middle metal, thus allowing the availability of an entire set of metal/oxide/metal nanowires ordered in a two-dimensional matrix and where single heterojunctions can be accessed individually.
Assuntos
Cristalização/métodos , Ouro/química , Nanopartículas Metálicas/química , Nanopartículas Metálicas/ultraestrutura , Níquel/química , Condutividade Elétrica , Substâncias Macromoleculares/química , Teste de Materiais , Conformação Molecular , Tamanho da Partícula , Propriedades de SuperfícieRESUMO
BACKGROUND AND OBJECTIVES: Standard treatment for patients with multiple myeloma is debulking chemotherapy with non-alkylating agents followed by a regimen to mobilize peripheral blood stem cells (PBSC) and the transplantation of the mobilized, autologous PBSC. The aim of this study was to evaluate the efficacy of a new regimen and compare it with that of a previous regimen. DESIGN AND METHODS: In a large cohort of 106 patients (group I) we administered a new pre-transplant program which includes 2 courses of pulsed-VAD (vincristine, adriamycin, dexamethasone) followed by 2 courses of DCEP (dexamethasone, cyclophosphamide, etoposide and cis-platinum). We compared the efficacy of this new VAD-DCEP sequence, in terms of mobilizing capacity, toxicity and anti-myeloma activity in comparison with that of the previous VAD-high-dose cyclophosphamide program (group II, 40 patients). RESULTS: In group I 81/106 (76.4%) patients yielded >or= 4x10(6)/kg CD34+ cells, as did 30/40 (75%) in group II but with a significantly higher toxicity in this latter group. In detail, 9 patients in group I (8.5%) had WHO grade III neutropenia versus 35 in group II (87.5%), 5 patients of group I (4.7%) had grade III thrombocytopenia versus 12 patients in group II (30%), and 8 patients in group I (7.5%) experienced an infections fever versus 9 patients in group II (22.5%). Therefore, nearly all patients in group II had to be admitted to hospital (39/40, 97.5%). There was a higher percentage of responses (CR+VGPR+PR) in group I than in group II: 73% versus 50% (p=0.02). INTERPRETATION AND CONCLUSIONS: the VAD-DCEP sequence has an adequate mobilizing capacity, without significant toxicity, and a good anti-myeloma activity, and therefore represents a safe and effective therapeutic approach for multiple myeloma patients at the onset of their disease.
Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Mieloma Múltiplo/tratamento farmacológico , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Cisplatino/administração & dosagem , Cisplatino/efeitos adversos , Estudos de Coortes , Terapia Combinada , Ciclofosfamida/administração & dosagem , Ciclofosfamida/efeitos adversos , Dexametasona/administração & dosagem , Dexametasona/efeitos adversos , Doxorrubicina/administração & dosagem , Doxorrubicina/efeitos adversos , Esquema de Medicação , Etoposídeo/administração & dosagem , Etoposídeo/efeitos adversos , Feminino , Mobilização de Células-Tronco Hematopoéticas , Humanos , Masculino , Melfalan/uso terapêutico , Pessoa de Meia-Idade , Mieloma Múltiplo/cirurgia , Terapia Neoadjuvante/efeitos adversos , Neutropenia/induzido quimicamente , Trombocitopenia/induzido quimicamente , Condicionamento Pré-Transplante/efeitos adversos , Transplante Autólogo , Resultado do Tratamento , Vincristina/administração & dosagem , Vincristina/efeitos adversosAssuntos
Doença Celíaca/complicações , Doença Celíaca/genética , Colite Ulcerativa/complicações , Colite Ulcerativa/genética , Fator V/genética , Glomerulonefrite Membranosa/complicações , Glomerulonefrite Membranosa/genética , Heterozigoto , Perna (Membro)/irrigação sanguínea , Trombose Venosa/complicações , Trombose Venosa/genética , Adulto , Doença Celíaca/patologia , Colite Ulcerativa/patologia , Glomerulonefrite Membranosa/patologia , Humanos , Perna (Membro)/patologia , Masculino , Trombose Venosa/patologiaRESUMO
We report on a patient with chronic myeloid leukemia (CML), which was detected by conventional cytogenetic analysis, to carry two different acquired and apparently balanced translocations, (9;22)(q34;q11.2) and (11;11)(p15;q13). By fluorescence in situ hybridization characterization, we were able to finely map the genomic regions involved in the translocation breakpoints and to disclose concomitant deletions adjacent to the breakpoints on the two derivative chromosomes 11 and the derivative chromosome 22, and the insertion of a segment from chromosome band 11q12.2 into the derivative chromosome 9. We discuss the putative mechanism that could have led to the formation of this complex rearrangement and speculate on the role in leukemogenesis played by the genes mapping at the breakpoints and within the deleted regions.
Assuntos
Coloração Cromossômica , Cromossomos Humanos Par 11/genética , Cromossomos Humanos Par 22/genética , Cromossomos Humanos Par 9/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Translocação Genética , Adulto , Antineoplásicos/uso terapêutico , Benzamidas , Células da Medula Óssea , Deleção Cromossômica , Mapeamento Cromossômico/métodos , Rearranjo Gênico , Humanos , Mesilato de Imatinib , Leucemia Mielogênica Crônica BCR-ABL Positiva/diagnóstico , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Masculino , Cromossomo Filadélfia , Piperazinas/uso terapêutico , Pirimidinas/uso terapêutico , Células Tumorais CultivadasRESUMO
BACKGROUND: Doxorubicin cardiotoxicity is one of the most serious side effects of the cyclophosphamide, doxorubicin, vincristine, and prednisone chemotherapy, regimen, especially among elderly patients. In the CEOP regimen, epirubicin was substituted for doxorubicin to reduce cardiotoxicity. METHODS: Between March 1984 and September 1998, 186 previously untreated patients with a histologically confirmed diagnosis of intermediate- or high-grade non-Hodgkin lymphoma according to the Working Formulation were treated with CEOP (cyclophosphamide, 750 mg/m(2), epirubicin, 75 mg/m(2), vincristine, 1.4 mg/m(2); and prednisone, 60 mg per day orally on Days 1-5). Of 186 patients, 85 (45.7%) had Stage IV disease, and 60 (32.3%) had an International Prognostic Index score > 2. Comorbidity was present in 36 patients (19.3%). RESULTS: Complete remission (CR) was achieved in 119 patients (64.3%), and partial remission was achieved in 30 patients (16.2%). Among the patients who achieved a CR, 95 (79.8%) were still disease free at a median follow-up time of 86.9 months (range, 14-200 months). The remaining 24 patients experienced disease recurrence, at a median follow-up time of 19 months (range, 3-101 months). The relative dose intensities were 0.69, 0.89, and 0.80 for vincristine, epirubicin, and cyclophosphamide, respectively. Two patients died of toxicity due to infection. Two patients, 59 and 73 years old, respectively, experienced arrhythmia. Another patient, age 64 years, who had a myocardial infarction 10 years earlier, had angina. One patient with hypertension experienced cardiac failure. No patients died of cardiac toxicity. CONCLUSION: Long-term follow-up confirmed that CEOP is an effective and well-tolerated chemotherapy regimen for intermediate- and high-grade lymphoma. The results were promising, especially among elderly patients.