966 resultados para Produto dose-comprimento (DLP)
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A «Empresa no Dia» (END) da Casa do Cidadão1, resultado da integração de vários serviços num único produto, vem influenciando positivamente e deverá continuar a contribuir para a competitividade das empresas em Cabo Verde, tanto no sector público como no privado; neste contexto a END poderá também contribuir para aumentar/acelerar a dinâmica da economia cabo-verdiana. Esta solução integrada constitui um importante exemplo da transição da E-Gov para a I-Gov em Cabo Verde, com base nas Tecnologias de Informação.A metodologia utilizada para o cumprimento dos objectivos apontados, consiste em recorrer aos dados estatísticos da CC, quer através de relatórios realizados pela instituição, quer por entrevistas efectuadas junto dos Gestores2 responsáveis, através do portal, como também junto ao coordenador da área de base de dados do Nosi3 e o conservador4 da Direcção Geral dos Registos e Notariado (DGRNI) da Praia.Há uma percepção de que a END constitui uma verdadeira reengenharia do processo de criação de firmas/sociedades em Cabo Verde, tendo em conta que as condições criadas permitiram celeridade do processo, diminuição do tempo de criação de uma empresa e diminuição do custo. Estas melhorias traduzem-se numa maior competitividade e desenvolvimento do tecido empresarial e, consequentemente, da economia nacional.
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PURPOSE: The prognostic impact of complete response (CR) achievement in multiple myeloma (MM) has been shown mostly in the context of autologous stem-cell transplantation. Other levels of response have been defined because, even with high-dose therapy, CR is a relatively rare event. The purpose of this study was to analyze the prognostic impact of very good partial response (VGPR) in patients treated with high-dose therapy. PATIENTS AND METHODS: All patients were included in the Intergroupe Francophone du Myelome 99-02 and 99-04 trials and treated with vincristine, doxorubicin, and dexamethasone (VAD) induction therapy followed by double autologous stem-cell transplantation (ASCT). Best post-ASCT response assessment was available for 802 patients. RESULTS: With a median follow-up of 67 months, median event-free survival (EFS) and 5-year EFS were 42 months and 34%, respectively, for 405 patients who achieved at least VGPR after ASCT versus 32 months and 26% in 288 patients who achieved only partial remission (P = .005). Five-year overall survival (OS) was significantly superior in patients achieving at least VGPR (74% v 61% P = .0017). In multivariate analysis, achievement of less than VGPR was an independent factor predicting shorter EFS and OS. Response to VAD had no impact on EFS and OS. The impact of VGPR achievement on EFS and OS was significant in patients with International Staging System stages 2 to 3 and for patients with poor-risk cytogenetics t(4;14) or del(17p). CONCLUSION: In the context of ASCT, achievement of at least VGPR is a simple prognostic factor that has importance in intermediate and high-risk MM and can be informative in more patients than CR.
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Second cancer risk assessment for radiotherapy is controversial due to the large uncertainties of the dose-response relationship. This could be improved by a better assessment of the peripheral doses to healthy organs in future epidemiological studies. In this framework, we developed a simple Monte Carlo (MC) model of the Siemens Primus 6 MV linac for both open and wedged fields that we then validated with dose profiles measured in a water tank up to 30 cm from the central axis. The differences between the measured and calculated doses were comparable to other more complex MC models and never exceeded 50%. We then compared our simple MC model with the peripheral dose profiles of five different linacs with different collimation systems. We found that the peripheral dose between two linacs could differ up to a factor of 9 for small fields (5 × 5 cm(2)) and up to a factor of 10 for wedged fields. Considering that an uncertainty of 50% in dose estimation could be acceptable in the context of risk assessment, the MC model can be used as a generic model for large open fields (≥10 × 10 cm(2)) only. The uncertainties in peripheral doses should be considered in future epidemiological studies when designing the width of the dose bins to stratify the risk as a function of the dose.
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Photodynamic therapy (PDT) is an effective clinical treatment for a number of different cancers. PDT can induce hypoxia and inflammation, pro-angiogenic side effects, which may counteract its angio-occlusive mechanism. The combination of PDT with anti-angiogenic drugs offers a possibility for improved anti-tumour outcome. We used two tumour models to test the effects of the clinically approved angiostatic tyrosine kinase inhibitors sunitinib, sorafenib and axitinib in combination with PDT, and compared these results with the effects of bevacizumab, the anti-VEGF antibody, for the improvement of PDT. Best results were obtained from the combination of PDT and low-dose axitinib or sorafenib. Molecular analysis by PCR revealed that PDT in combination with axitinib suppressed VEGFR-2 expression in tumour vasculature. Treatment with bevacizumab, although effective as monotherapy, did not improve PDT outcome. In order to test for tumour vessel normalization effects, axitinib was also applied prior to PDT. The absence of improved PDT outcome in these experiments, as well as the lack of increased oxygenation in axitinib-treated tumours, suggests that vascular normalization did not occur. The current data imply that there is a future for certain anti-angiogenic agents to further improve the efficacy of photodynamic anti-cancer therapy.
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Nos preparos conservacionistas de solo, os resíduos e a rugosidade diminuem o escoamento superficial e permitem aumentar a distância entre os terraços, em relação aos preparos convencionais, apesar do aumento da consolidação da superfície que ocorre especialmente na semeadura direta. Os terraços devem ter uma distância tal que o escoamento superficial não ocasione a remoção do resíduo e o aumento da erosão ou que o volume de água que escoa entre um terraço e outro seja armazenado ou drenado pelo canal. Utilizando chuva simulada e fluxos extras de água no período de 1992 a 1994, na Estação Experimental Agronômica da UFRGS, em Eldorado do Sul (RS), determinaram-se distâncias entre terraços para os tratamentos sem preparo do solo e escarificação, na presença dos resíduos culturais de milho, trigo e trigo + milho, em Podzólico Vermelho-Amarelo com 0,066 m m-1 de declividade, com base nos critérios da falha do resíduo cultural e na capacidade de armazenamento de água no canal. Pelo critério da capacidade de armazenamento de água no canal, a menor distância entre terraços (27 a 43 m) ocorreu no tratamento escarificação com o resíduo de milho, enquanto a maior (44 a 60 m) foi no sem preparo com resíduo de milho. Pelo critério da falha do resíduo cultural, no entanto, a menor distância (106 a 130 m) verificou-se no tratamento sem preparo com resíduo de trigo e a maior (328 a 483 m) no tratamento sem preparo com resíduo de milho.
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Introduction: As imatinib pharmacokinetics are highly variable, plasma levels differ largely between patients under the same dosage. Retrospective studies in chronic myeloid leukemia (CML) patients showed significant correlations between low levels and suboptimal response, as well as between high levels and poor tolerability. Monitoring of trough plasma levels, targeting 1000 μg/L and above, is thus increasingly advised. Our study was launched to assess prospectively the clinical usefulness of systematic imatinib TDM in CML patients. This preliminary analysis addresses the appropriateness of the dosage adjustment approach applied in this study, which targets the recommended trough level and allows an interval of 4-24 h after last drug intake for blood sampling. Methods: Blood samples from the first 15 patients undergoing 1st TDM were obtained 1.5-25 h after last dose. Imatinib plasma levels were measured by LC-MS/MS and the concentrations were extrapolated to trough based on a Bayesian approach using a population pharmacokinetic model. Trough levels were predicted to differ significantly from the target in 12 patients (10 <750 μg/L; 2 >1500 μg/L along with poor tolerance) and individual dose adjustments were proposed. 8 patients underwent a 2nd TDM cycle. Trough levels of 1st and 2nd TDM were compared, the sample drawn 1.5 h after last dose (during distribution phase) was excluded from the analysis. Results: Individual dose adjustments were applied in 6 patients. Observed concentrations extrapolated to trough ranged from 360 to 1832 μg/L (median 725; mean 810, CV 52%) on 1st TDM and from 720 to 1187 μg/L (median 950; mean 940, CV 18%) on 2nd TDM cycle. Conclusions: These preliminary results suggest that TDM of imatinib using a Bayesian interpretation is able to target the recommended trough level of 1000 μg/L and to reduce the considerable differences in trough level exposure between patients (with CV decreasing from 52% to 18%). While this may simplify blood collection in daily practice, as samples do not have to be drawn exactly at trough, the largest possible interval to last drug intake yet remains preferable to avoid sampling during distribution phase leading to biased extrapolation. This encourages the evaluation of the clinical benefit of a routine TDM intervention in CML patients, which the randomized Swiss I-COME trial aims to.
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OBJECTIVE: To assess the efficacy and tolerability of canakinumab, a fully human anti-interleukin-1β monoclonal antibody, for the treatment of acute gouty arthritis. METHODS: In this 8-week, single-blind, double-dummy, dose-ranging study, patients with acute gouty arthritis whose disease was refractory to or who had contraindications to nonsteroidal antiinflammatory drugs and/or colchicine were randomized to receive a single subcutaneous dose of canakinumab (10, 25, 50, 90, or 150 mg; n = 143) or an intramuscular dose of triamcinolone acetonide (40 mg; n = 57). Patients assessed pain using a 100-mm visual analog scale. RESULTS: Seventy-two hours after treatment, a statistically significant dose response was observed for canakinumab. All canakinumab doses were associated with numerically less pain than triamcinolone acetonide; thus, a dose with equivalent efficacy to triamcinolone acetonide 72 hours after treatment could not be determined. The reduction from baseline in pain intensity with canakinumab 150 mg was greater than with triamcinolone acetonide 24, 48, and 72 hours after treatment (differences of -11.5 mm [P = 0.04], -18.2 mm [P = 0.002], and -19.2 mm [P < 0.001], respectively), and 4, 5, and 7 days after treatment (all P < 0.05). Canakinumab significantly reduced the risk of recurrent flares versus triamcinolone acetonide (P ≤ 0.01 for all doses) (relative risk reduction 94% for canakinumab 150 mg versus triamcinolone acetonide). The overall incidence of adverse events was similar for canakinumab (41%) and triamcinolone acetonide (42%); most were mild or moderate in severity. CONCLUSION: Our findings indicate that canakinumab 150 mg provides rapid and sustained pain relief in patients with acute gouty arthritis, and significantly reduces the risk of recurrent flares compared with triamcinolone acetonide.
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A utilização agronômica do biossólido tem sido vista como a forma mais viável para sua disposição; entretanto, além do conhecimento técnico de suas propriedades como fertilizante, aspectos qualitativos, econômicos e práticos de seu uso são importantes para o produtor. O biossólido produzido pela Companhia de Saneamento de Brasília (CAESB) apresentou uma grande variabilidade entre as concentrações dos nutrientes a cada amostra coletada mensalmente no período entre agosto/1995 e julho/1996 e entre as estações de tratamento de origem do material. A variabilidade, maior para os macronutrientes (Ca, N, P, K, Mg e S) e menor para os micronutrientes e metais pesados, determina a necessidade de ajuste no cálculo das quantidades do material a cada aplicação. Apesar de fornecido gratuitamente, os usuários pagam pelo transporte do biossólido, o qual, pelo seu elevado conteúdo de água, só é viável até determinada distância. Nas condições deste trabalho, a distância máxima foi de 122 km. A simulação de secagem do produto mostrou que, reduzindo o conteúdo de água da pasta de 90 dag kg-1 para 70 dag kg-1, a distância de transporte aumenta de 122 para 365 km, ampliando a área de abrangência de seu uso. A aplicação de 54 t ha-1 de biossólido úmido (90 dag kg-1) apresentou a melhor relação benefício/custo (retorno de R$ 1,12 para cada R$ 1,00 investido no material), comparada às demais aplicações e às adubações com fertilizantes minerais (todas com retornos abaixo de R$ 1,00 para cada R$ 1,00 investido; a maior dose de biossólido teve retorno negativo). Embora tenha apresentado melhor desempenho comparativo, o que pode qualificá-la, preliminarmente, como dose para recomendação, a aplicação de 54 t ha-1 de biossólido úmido requer a movimentação e manipulação de um grande volume de material, o que pode ser um fator de limitação de seu uso.
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OBJECTIVE: To study the benefits of a low-dose stimulation (LDS) protocol with purified urinary follicle-stimulating hormone in patients with polycystic ovaries who have presented previously with a very high ovarian response to a standard hMG stimulation. DESIGN: Cohort study. SETTING: Fertility center in a university hospital. PATIENT(S): Sixty-one patients involved in an IVF/ICSI program from January 1995 to December 1996. INTERVENTION(S): The patients were first stimulated with a standard protocol using hMG and presented with a very high ovarian response. These patients were then stimulated a second time using a low-dose protocol. Cryopreserved embryos were transferred in later artificial or natural cycles until to December 1999. MAIN OUTCOME MEASURE(S): Number of gonadotropin ampules; estradiol level on the day of ovulation induction; follicles, oocytes, and cryopreserved zygotes; fertilization, implantation, and pregnancy rates; and number of ovarian hyperstimulation syndromes (OHSS). RESULT(S): The number of ampules used, the estradiol level reached, and the number of oocytes obtained were significantly lower under the LDS than the standard protocol. High implantation (21.8%) and clinical pregnancy (38.4%) rates were obtained after LDS. The cumulated deliveries per cycle started and per patient were, respectively, 41.6% and 52.5%. Five patients suffered OHSS with the standard protocol, and none with the LDS. CONCLUSION(S): The LDS protocol offers a safe and efficient treatment for patients who present with echographic polycystic ovaries and are at risk of an excessive ovarian response to standard IVF stimulation protocols.
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BACKGROUND: The aim of this study was to assess the pharmacology, toxicity and activity of high-dose ifosfamide mesna +/- GM-CSF administered by a five-day continuous infusion at a total ifosfamide dose of 12-18 g/m2 in adult patients with advanced sarcomas. PATIENTS AND METHODS: Between January 1991 and October 1992 32 patients with advanced or metastatic sarcoma were entered the study. Twenty-seven patients were pretreated including twenty-three with prior ifosfamide at less than 8 g/m2 total dose/cycle. In 25 patients (27 cycles) extensive pharmacokinetic analyses were performed. RESULTS: The area under the plasma concentration-time curve (AUC) for ifosfamide increased linearly with dose while the AUC's of the metabolites measured in plasma by thin-layer chromatography did not increase with dose, particularly that of the active metabolite isophosphoramide mustard. Furthermore the AUC of the inactive carboxymetabolite did not increase with dose. Interpatient variability of pharmacokinetic parameters was high. Dose-limiting toxicity was myelosuppression at 18 g/m2 total dose with grade 4 neutropenia in five of six patients and grade 4 thrombocytopenia in four of six patients. Therefore the maximum tolerated dose was considered to be 18 g/m2 total dose. There was one CR and eleven PR in twenty-nine evaluable patients (overall response rate 41%). CONCLUSION: Both the activation and inactivation pathways of ifosfamide are non-linear and saturable at high-doses although the pharmacokinetics of the parent drug itself are dose linear. Ifosfamide doses greater than 14-16 g/m2 per cycle appear to result in a relative decrease of the active metabolite isophosphoramide mustard. These data suggest a dose-dependent saturation or even inhibition of ifosfamide metabolism by increasing high dose ifosfamide and suggest the need for further metabolic studies.
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Background and aim of the study: Genomic gains and losses play a crucial role in the development and progression of DLBCL and are closely related to gene expression profiles (GEP), including the germinal center B-cell like (GCB) and activated B-cell like (ABC) cell of origin (COO) molecular signatures. To identify new oncogenes or tumor suppressor genes (TSG) involved in DLBCL pathogenesis and to determine their prognostic values, an integrated analysis of high-resolution gene expression and copy number profiling was performed. Patients and methods: Two hundred and eight adult patients with de novo CD20+ DLBCL enrolled in the prospective multicentric randomized LNH-03 GELA trials (LNH03-1B, -2B, -3B, 39B, -5B, -6B, -7B) with available frozen tumour samples, centralized reviewing and adequate DNA/RNA quality were selected. 116 patients were treated by Rituximab(R)-CHOP/R-miniCHOP and 92 patients were treated by the high dose (R)-ACVBP regimen dedicated to patients younger than 60 years (y) in frontline. Tumour samples were simultaneously analysed by high resolution comparative genomic hybridization (CGH, Agilent, 144K) and gene expression arrays (Affymetrix, U133+2). Minimal common regions (MCR), as defined by segments that affect the same chromosomal region in different cases, were delineated. Gene expression and MCR data sets were merged using Gene expression and dosage integrator algorithm (GEDI, Lenz et al. PNAS 2008) to identify new potential driver genes. Results: A total of 1363 recurrent (defined by a penetrance > 5%) MCRs within the DLBCL data set, ranging in size from 386 bp, affecting a single gene, to more than 24 Mb were identified by CGH. Of these MCRs, 756 (55%) showed a significant association with gene expression: 396 (59%) gains, 354 (52%) single-copy deletions, and 6 (67%) homozygous deletions. By this integrated approach, in addition to previously reported genes (CDKN2A/2B, PTEN, DLEU2, TNFAIP3, B2M, CD58, TNFRSF14, FOXP1, REL...), several genes targeted by gene copy abnormalities with a dosage effect and potential physiopathological impact were identified, including genes with TSG activity involved in cell cycle (HACE1, CDKN2C) immune response (CD68, CD177, CD70, TNFSF9, IRAK2), DNA integrity (XRCC2, BRCA1, NCOR1, NF1, FHIT) or oncogenic functions (CD79b, PTPRT, MALT1, AUTS2, MCL1, PTTG1...) with distinct distribution according to COO signature. The CDKN2A/2B tumor suppressor locus (9p21) was deleted homozygously in 27% of cases and hemizygously in 9% of cases. Biallelic loss was observed in 49% of ABC DLBCL and in 10% of GCB DLBCL. This deletion was strongly correlated to age and associated to a limited number of additional genetic abnormalities including trisomy 3, 18 and short gains/losses of Chr. 1, 2, 19 regions (FDR < 0.01), allowing to identify genes that may have synergistic effects with CDKN2A/2B inactivation. With a median follow-up of 42.9 months, only CDKN2A/2B biallelic deletion strongly correlates (FDR p.value < 0.01) to a poor outcome in the entire cohort (4y PFS = 44% [32-61] respectively vs. 74% [66-82] for patients in germline configuration; 4y OS = 53% [39-72] vs 83% [76-90]). In a Cox proportional hazard prediction of the PFS, CDKN2A/2B deletion remains predictive (HR = 1.9 [1.1-3.2], p = 0.02) when combined with IPI (HR = 2.4 [1.4-4.1], p = 0.001) and GCB status (HR = 1.3 [0.8-2.3], p = 0.31). This difference remains predictive in the subgroup of patients treated by R-CHOP (4y PFS = 43% [29-63] vs. 66% [55-78], p=0.02), in patients treated by R-ACVBP (4y PFS = 49% [28-84] vs. 83% [74-92], p=0.003), and in GCB (4y PFS = 50% [27-93] vs. 81% [73-90], p=0.02), or ABC/unclassified (5y PFS = 42% [28-61] vs. 67% [55-82] p = 0.009) molecular subtypes (Figure 1). Conclusion: We report for the first time an integrated genetic analysis of a large cohort of DLBCL patients included in a prospective multicentric clinical trial program allowing identifying new potential driver genes with pathogenic impact. However CDKN2A/2B deletion constitutes the strongest and unique prognostic factor of chemoresistance to R-CHOP, regardless the COO signature, which is not overcome by a more intensified immunochemotherapy. Patients displaying this frequent genomic abnormality warrant new and dedicated therapeutic approaches.
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Aim: To compare a less intensive regimen based on high-dose imatinib (IM) to an intensive IM/HyperCVAD regimen in adults with Ph+ ALL, in terms of early response and outcome after stem cell transplantation (SCT). Methods: Patients aged 18-60 years with previously untreated Ph+ ALL not evolving from chronic myeloid leukemia were eligible if no contra-indication to chemotherapy and SCT (ClinicalTrials.gov ID, NCT00327678). After a steroid prephase allowing Ph and/or BCR-ABL diagnosis, cycle 1 differed between randomization arms. In arm A (IM-based), IM was given at 800 mg on day 1-28, combined with vincristine (2 mg, day 1, 8, 15, 22) and dexamethasone (40 mg, day 1-2, 8-9, 15-16, and 22-23) only. In arm B (IM/HyperCVAD), IM was given at 800 mg on day 1-14, combined with adriamycin (50 mg/m2, day 4), cyclophosphamide (300 mg/m2/12h, day 1, 2, 3), vincristine (2 mg, day 4 and 11), and dexamethasone (40 mg, day 1-4 and 11-14). All patients received a cycle 2 combining high-dose methotrexate (1 g/m2, day 1) and AraC (3 g/m2/12h, day 2 and 3) with IM at 800 mg on day 1-14, whatever their response. Four intrathecal infusions were given during this induction/consolidation period. Minimal residual disease (MRD) was centrally evaluated by quantitative RQ-PCR after cycle 1 (MRD1) and cycle 2 (MRD2). Major MRD response was defined as BCR-ABL/ABL ratio <0.1%. Then, all patients were to receive allogeneic SCT using related or unrelated matched donor stem cells or autologous SCT if no donor and a major MRD2 response. IM/chemotherapy maintenance was planned after autologous SCT. In the absence of SCT, patients received alternating cycles 1 (as in arm B) and cycles 2 followed by maintenance, like in the published IM/HyperCVAD regimen. The primary objective was non-inferiority of arm A in term of major MRD2 response. Secondary objectives were CR rate, SCT rate, treatment- and transplant-related mortality, relapse-free (RFS), event-free (EFS) and overall (OS) survival. Results: Among the 270 patients randomized between May 2006 and August 2011, 265 patients were evaluable for this analysis (133 arm A, 132 arm B; median age, 47 years; median follow-up, 40 months). Main patient characteristics were well-balanced between both arms. Due to higher induction mortality in arm B (9 versus 1 deaths; P=0.01), CR rate was higher in the less intensive arm A (98% versus 89% after cycle 1 and 98% versus 91% after cycle 2; P= 0.003 and 0.006, respectively). A total of 213 and 205 patients were evaluated for bone marrow MRD1 and MRD2. The rates of patients reaching major MRD response and undetectable MRD were 45% (44% arm A, 46% arm B; P=0.79) and 10% (in both arms) at MRD1 and 66% (68% arm A, 63.5% arm B; P=0.56) and 25% (28% arm A, 22% arm B; P=0.33) at MRD2, respectively. The non-inferiority primary endpoint was thus demonstrated (P= 0.002). Overall, EFS was estimated at 42% (95% CI, 35-49) and OS at 51% (95% CI, 44-57) at 3 years, with no difference between arm A and B (46% versus 38% and 53% versus 49%; P=0.25 and 0.61, respectively). Of the 251 CR patients, 157 (80 arm A, 77 arm B) and 34 (17 in both arms) received allogeneic and autologous SCT in first CR, respectively. Allogeneic transplant-related mortality was similar in both arms (31.5% versus 22% at 3 years; P=0.51). Of the 157 allografted patients, 133 had MRD2 evaluation and 89 had MRD2 <0.1%. In these patients, MRD2 did not significantly influence post-transplant RFS and OS, either when tested with the 0.1% cutoff or as a continuous log covariate. Of the 34 autografted patients, 31 had MRD2 evaluation and, according to the protocol, 28 had MRD2 <0.1%. When restricting the comparison to patients achieving major MRD2 response and with the current follow-up, a trend for better results was observed after autologous as compared to allogeneic SCT (RFS, 63% versus 49.5% and OS, 69% versus 58% at 3 years; P=0.35 and P=0.08, respectively). Conclusions: In adults, the use of TK inhibitors (TKI) has markedly improved the results of Ph+ ALL therapy, now close to those observed in Ph-negative ALL. We demonstrated here that chemotherapy intensity may be safely reduced when associated with high-dose IM. We will further explore this TKI-based strategy using nilotinib prior to SCT in our next GRAAPH-2013 trial. The trend towards a better outcome after autologous compared to allogeneic SCT observed in MRD responders validates MRD as an important early surrogate endpoint for treatment stratification and new drug investigation in this disease.
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O nitrogênio (N) é o nutriente absorvido em maiores quantidades pelo milho e o que mais influencia o rendimento de grãos, tendo sua dinâmica no sistema solo-planta alterada pelo manejo. Objetivou-se avaliar doses e épocas de aplicação de N na cultura do milho sob sistema plantio direto (SPD) recém-instalado. O estudo foi realizado na fazenda experimental da UNESP/FEIS, no município de Selvíria (MS), em um Latossolo Vermelho distrófico, durante os anos agrícolas de 1998/99 e de 1999/00. O delineamento experimental foi de blocos casualizados, com 19 tratamentos e quatro repetições, dispostos em esquema fatorial incompleto 6 x 3 + 1 (testemunha: 0 kg ha-1), constituídos por seis combinações de épocas de aplicação de N (todo na semeadura, todo no estádio de 4 a 6 folhas, todo no estádio de 8 a 10 folhas, ½ semeadura + ½ no estádio de 4 a 6 folhas, ½ semeadura + ½ no estádio de 8 a 10 folhas e ½ no estádio de 4 a 6 folhas e ½ no estádio de 8 a 10 folhas) com 4 doses de N-uréia (0, 60, 120 e 180 kg ha-1). Foram avaliados os teores de N-NH4+, N-NO3-, N mineral e N total, nas profundidades de 0,0 a 0,10; 0,10 a 0,20 e 0,20 a 0,40 m, na época do florescimento do milho. Foram avaliados: a altura da planta e da espiga, o teor de N na folha, na época do florescimento, o teor de N no grão, o número de fileiras de grãos por espiga e de grãos por fileira, o peso de 1.000 grãos e a produtividade. O teor de NH4+ foi superior ao de NO3-, nas mesmas profundidades, em ambos os cultivos. A máxima eficiência técnica para a produtividade de milho foi alcançada com a dose de 166 kg ha-1 de N, e a máxima eficiência econômica, considerando a relação preço do N/preço do produto de 8,25/1, foi alcançada com a dose de 126 kg ha-1 de N, aplicada metade na semeadura e metade no estádio de 4 a 6 folhas.
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A dose-response strategy may not only allow investigation of the impact of foods and nutrients on human health but may also reveal differences in the response of individuals to food ingestion based on their metabolic health status. In a randomized crossover study, we challenged 19 normal-weight (BMI: 20-25 kg/m(2)) and 18 obese (BMI: >30 kg/m(2)) men with 500, 1000, and 1500 kcal of a high-fat (HF) meal (60.5% energy from fat). Blood was taken at baseline and up to 6 h postprandially and analyzed for a range of metabolic, inflammatory, and hormonal variables, including plasma glucose, lipids, and C-reactive protein and serum insulin, glucagon-like peptide-1, interleukin-6 (IL-6), and endotoxin. Insulin was the only variable that could differentiate the postprandial response of normal-weight and obese participants at each of the 3 caloric doses. A significant response of the inflammatory marker IL-6 was only observed in the obese group after ingestion of the HF meal containing 1500 kcal [net incremental AUC (iAUC) = 22.9 ± 6.8 pg/mL × 6 h, P = 0.002]. Furthermore, the net iAUC for triglycerides significantly increased from the 1000 to the 1500 kcal meal in the obese group (5.0 ± 0.5 mmol/L × 6 h vs. 6.0 ± 0.5 mmol/L × 6 h; P = 0.015) but not in the normal-weight group (4.3 ± 0.5 mmol/L × 6 h vs. 4.8 ± 0.5 mmol/L × 6 h; P = 0.31). We propose that caloric dose-response studies may contribute to a better understanding of the metabolic impact of food on the human organism. This study was registered at clinicaltrials.gov as NCT01446068.
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Um sistema radicular bem desenvolvido na gramínea forrageira é necessário para a formação e sustentação da planta e, como conseqüência, para a boa produtividade da pastagem. Objetivou-se avaliar características radiculares da Brachiaria brizantha cv. Marandu, em resposta a combinações de doses de N e S na solução nutritiva, empregando sílica como substrato, num experimento realizado em casa de vegetação no período de setembro a dezembro de 2001. Utilizou-se o esquema fatorial 5² fracionado, com 13 combinações de N e S, em mg L-1, respectivamente: 14 e 3,2; 14 e 32; 14 e 80; 126 e 12,8; 126 e 64; 210 e 3,2; 210 e 32; 210 e 80; 336 e 12,8; 336 e 64; 462 e 3,2; 462 e 32 e 462 e 80, as quais foram distribuídas segundo o delineamento de blocos ao acaso, com quatro repetições. Foram realizados dois cortes nas plantas. Após o segundo corte, as raízes foram separadas do substrato e avaliadas. A concentração de N e os acúmulos de N e de S nas raízes do capim mostraram-se dependentes da interação entre as doses de N e S. A dose de N foi determinante para o comprimento, superfície, produção de massa seca, relação comprimento:massa seca e concentração de S no tecido das raízes da forrageira. A produção de massa seca, o comprimento, a superfície das raízes e o acúmulo total de N e de S nas plantas do capim tiveram significativas correlações entre si.