Benefits of the Intermittent Use of 6-Mercaptopurine and Methotrexate in Maintenance Treatment for Low-Risk Acute Lymphoblastic Leukemia in Children: Randomized Trial From the Brazilian Childhood Cooperative Group Protocol ALL-99

Purpose To describe event-free survival (EFS) and toxicities in children with low-risk acute lymphoblastic leukemia (ALL) assigned to receive either continuous 6-mercaptopurine (6-MP) and weekly methotrexate (MIX) or intermittent 6-MP with intermediate-dose MTX, as maintenance treatment. Patients and Methods Between October 1, 2000, and December 31, 2007, 635 patients with low-risk ALL were enrolled onto Brazilian Childhood Cooperative Group for ALL Treatment (GBTLI) ALL-99 protocol. Eligible children (n=544) were randomly allocated to receive either continuous 6-ME/MIX (group 1, n 272) or intermittent 6-MP (100 mg/m(2)/d for 10 days, with 11 days resting) and MIX (200 mg/m(2) every 3 weeks; group 2, n = 272). Results The 5-year overall survival (OS) and EFS were 92.5% +/- 1.5% SE and 83.6% +/- 2.1% SE, respectively. According to maintenance regimen, the OS was 91.4% +/- 2.2% SE (group 1) and 93.6% +/- 2.1% SE (group 2; P=.28) and EFS 80.9% +/- 3.2% SE (group 1) and 86.5% +/- 2.8% SE (group 2; P=.089). Remarkably, the intermittent regimen led to significantly higher EFS among boys (85.7% v 74.9% SE; P=027), while no difference was seen for girls (87.0% v 88.8% SE; P=.78). Toxic episodes were recorded in 226 and 237 children, respectively. Grade 3 to 4 toxic events for groups 1 and 2 were, respectively, 273 and 166 for hepatic dysfunction (P=.002), and 772 and 636 for hematologic episodes (P=.005). Deaths on maintenance were: seven (group 1) and one (group 2). Conclusion The intermittent use of 6-MP and MIX in maintenance is a less toxic regimen, with a trend toward better long-term EFS. Boys treated with the intermittent schedule had significantly better EFS.

Diabetes and Vascular Disease: Basic Concepts of Nitric Oxide Physiology, Endothelial Dysfunction, Oxidative Stress and Therapeutic Possibilities

The vascular manifestations associated with diabetes mellitus (DM) result from the dysfunction of several vascular physiology components mainly involving the endothelium, vascular smooth muscle and platelets. It is also known that hyperglycemia-induced oxidative stress plays a role in the development of this dysfunction. This review considers the basic physiology of the endothelium, especially related to the synthesis and function of nitric oxide. We also discuss the pathophysiology of vascular disease associated with DM. This includes the role of hyperglycemia in the induction of oxidative stress and the role of advanced glycation end-products. We also consider therapeutic strategies.

Effect of isoflavone extracts from Glycine max on human endothelial cell damage and on nitric oxide production

Objective: In this study, we determined the protective effect of isoflavones from Glycine max on human umbilical vein endothelial cell (ECV304) damage induced by hydrogen peroxide (H(2)O(2)) and on nitric oxide (NO) production. Methods: We studied the regulation of NO synthesis in cultured human endothelial cells by phytoestrogens contained in soy extracts in the presence or absence of ICI 182,780 or N(omega)-nitro-L-arginine methyl esther and determined the protective effect of these isoflavones on ECV304 damage induced by H(2)O(2). Results: We show that soy extracts activate NO synthesis in endothelial cells and protect against cell damage. Conclusions: In conclusion, soy isoflavones markedly protect ECV304 cells against H(2)O(2) damage and promote NO synthesizing. Therefore, these isoflavones call potentially act as an NO promoter and as an antioxidant.