Synthesis of a bis(diketiminate)bromosamarium(III) complex and its activity in the polymerization of methyl methacrylate

A bis(diketiminate)bromosamarium(III) complex was successfully synthesized and, after the activation with butyl lithium, was shown to be active in methyl methacrylate (MMA) polymerization. The effects of temperature, polymerization time and catalyst concentration were studied. Activities of ca. 16,000 g of poly(methyl methacrylate) (PMMA) per mol of samarium and per hour were obtained under optimum conditions (0 degrees C and a MMA/catalyst molar ratio of 90/1), providing a polymer with a molar mass M-n > 23.0 kg mol(-1) and a molar mass distribution (M-w/ M-n) < 1.4. After 1 h of polymerization, conversions of MMA as high as 90% were observed. (c) 2006 Elsevier B.V. All rights reserved.317214915

Endoglucanase and total cellulase from newly isolated Rhizopus oryzae and Trichoderma reesei: production, characterization, and thermal stability

A multienzymatic complex production was evaluated, as well as endoglucanase and total cellulase characterization, during solid-state fermentation of rice industry wastes with Rhizopus oryzae CCT 7560 (newly isolated microorganism) and Trichoderma reesei QM 9414 (control). R. oryzae produced enzymes with higher activity at 15 h of fermentation (5.1 and 2.3 U g−1 to endoglucanase and total cellulase), while T. reesei produced them at 55 h (15.3 and 2.8 U g−1 to endoglucanase and total cellulase). The optimum temperature for total cellulase and endoglucanase was 60 °C. For Trichoderma and Rhizopus, the optimum pH was 5.0 and 6.0 for total cellulase and 6.0 and 5.0 for endoglucanase, respectively. The enzymes produced by Rhizopus presented higher stability at the temperature range evaluated (25–100 °C); the endoglucanase KM value was 20 times lower than the one found for Trichoderma. The characterization of the cellulolytic enzymes from the fungal species native of rice husk revealed that they can be more efficient than the genetically modified enzymes when rice husk and rice bran are used as substrates

Estimated GFR and the Effect of Intensive Blood Pressure Lowering after Acute Intracerebral Hemorrhage

Background: The kidney-brain interaction has been a topic of growing interest. Past studies of the effect of kidney function on intracerebral hemorrhage (ICH) outcomes have yielded inconsistent findings. Although the second, main phase of the Intensive Blood Pressure Reduction in Acute Cerebral Hemorrhage Trial (INTERACT2) suggests the effectiveness of early intensive blood pressure (BP) lowering in improving functional recovery after ICH, the balance of potential benefits and harms of this treatment in those with decreased kidney function remains uncertain. Study Design: Secondary analysis of INTERACT2, which randomly assigned patients with ICH with elevated systolic BP (SBP) to intensive (target SBP &lt; 140 mm Hg) or contemporaneous guideline-based (target SBP &lt; 180 mm Hg) BP management. Setting &amp; Participants: 2,823 patients from 144 clinical hospitals in 21 countries. Predictors Admission estimated glomerular filtration rates (eGFRs) of patients were categorized into 3 groups based on the CKD-EPI (Chronic Kidney Disease Epidemiology Collaboration) creatinine equation: normal or high, mildly decreased, and moderately to severely decreased (&gt;90, 60-90, and &lt;60 mL/min/1.73 m2, respectively). Outcomes: The effect of admission eGFR on the primary outcome of death or major disability at 90 days (defined as modified Rankin Scale scores of 3-6) was analyzed using a multivariable logistic regression model. Potential effect modification of intensive BP lowering treatment by admission eGFR was assessed by interaction terms. Results: Of 2,623 included participants, 912 (35%) and 280 (11%) had mildly and moderately/severely decreased eGFRs, respectively. Patients with moderately/severely decreased eGFRs had the greatest risk for death or major disability at 90 days (adjusted OR, 1.82; 95% CI, 1.28-2.61). Effects of early intensive BP lowering were consistent across different eGFRs (P = 0.5 for homogeneity). Limitations: Generalizability issues arising from a clinical trial population. Conclusions: Decreased eGFR predicts poor outcome in acute ICH. Early intensive BP lowering provides similar treatment effects in patients with ICH with decreased eGFRs