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Brain microbleeds are increased in chronic kidney disease (CKD) and their presence increases risk of cognitive decline and stroke. We examined the interaction between CKD and brain microhemorrhages (the neuropathological substrate of microbleeds) in mouse and cell culture models and studied progression of microbleed burden on serial brain imaging from humans. Mouse studies: Two CKD models were investigated: adenine-induced tubulointerstitial nephritis and surgical 5/6 nephrectomy. Cell culture studies: bEnd.3 mouse brain endothelial cells were grown to confluence, and monolayer integrity was measured after exposure to 5–15% human uremic serum or increasing concentrations of urea. Human studies: Progression of brain microbleeds was evaluated on serial MRI from control, pre-dialysis CKD, and dialysis patients. Microhemorrhages were increased 2–2.5-fold in mice with CKD independent of higher blood pressure in the 5/6 nephrectomy model. IgG staining was increased in CKD animals, consistent with increased blood–brain barrier permeability. Incubation of bEnd.3 cells with uremic serum or elevated urea produced a dose-dependent drop in trans-endothelial electrical resistance. Elevated urea induced actin cytoskeleton derangements and decreased claudin-5 expression. In human subjects, prevalence of microbleeds was 50% in both CKD cohorts compared with 10% in age-matched controls. More patients in the dialysis cohort had increased microbleeds on follow-up MRI after 1.5 years. CKD disrupts the blood–brain barrier and increases brain microhemorrhages in mice and microbleeds in humans. Elevated urea alters the actin cytoskeleton and tight junction proteins in cultured endothelial cells, suggesting that these mechanisms explain (at least in part) the microhemorrhages and microbleeds observed in the animal and human studies. [ABSTRACT FROM AUTHOR]

In present work, hydrogenation of furfural to furfuryl alcohol (FA) is studied over Co-Cu/SBA-15 as FA has wide range of industrial applications such as in the resin production, acid proof bricks, fibre glass, fibre concrete etc. The effects of different operating parameters such as temperature, pressure, catalyst amount, and furfural to 2-propanol molar ratio on the conversion of furfural to FA were determined and parameters were optimized by implementing Taguchi method as statistical tool. At the optimized conditions, the yield of FA was 96.7 %. The yield of FA was influenced by the parameters such as temperature and pressure significantly, as obtained by analysis of variance. Kinetic study revealed that the reaction followed pseudo-first order pathway with an activation energy of 9.2 kcal mol. Graphical Abstract: [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

This paper deals with esterification of free fatty acids (FFAs) in acid oil (a byproduct of oil refining) to obtain biodiesel. Sulfonic acid-functionalized silica (SiO-Pr-SOH) was used as promising solid-acid catalyst. The conditions affecting conversion to fatty acid methyl esters (FAME), for example reaction temperature, reaction time, catalyst concentration, and methanol-to-oil molar ratio, were investigated and optimized by use of the Taguchi method. The highest conversion obtained under the optimized conditions was 96.78 % after 8 h. Analysis of variance revealed that temperature was the most significant factor effecting conversion among the four conditions studied. The experimental results were found to fit a pseudo first-order kinetic law. SiO-Pr-SOH is a highly effective, reusable, and environmentally benign catalyst for biodiesel production from waste low-cost oil feedstock with a high FFA content. [ABSTRACT FROM AUTHOR]

Background: Conventional therapeutic options for patients with advanced upper gastrointestinal cancers (UGIC) are limited. Following first-line treatments, some patients are offered experimental therapies, including participation in Phase I trials. This study aims to describe the experience of UGIC patients treated in a dedicated Phase I unit. Methods: Patient, tumour and treatment characteristics, and clinical outcomes of UGIC patients treated consecutively at the Drug Development Unit, Royal Marsden Hospital, between 2005 and 2009, were recorded. Results: Ninety-six patients who previously received a median of 2 (range 1-4) lines of chemotherapies were treated in 30 Phase I trials. Of 81 evaluable patients, 9 achieved RECIST-objective response (11 %) with a 6-month clinical benefit rate of 14 %. Median progression free and overall survival were 7.7 weeks [95 %CI 7.7 (6.4-9.0)] and 19.1 weeks (95 %CI 17.5-20.8), respectively. Grade 3 or 4 toxicities were observed in 37 patients (39 %) and led to trial discontinuation in 9 (9 %); no toxicity-related death was recorded. In the multivariate analysis, serum albumin (<35 g/dl, HR2.0, p = 0.002) and lactate dehydrogenase (>192 μmol/l, HR1.7, p = 0.016) were prognostic of overall survival. Conclusion: Phase I clinical trials can be considered a reasonable option in selected patients with relapsed UGIC. The use of objective prognosticators may improve selection and risk/benefit profile of patients. [ABSTRACT FROM AUTHOR]

Conversion of high free fatty acids (FFA) containing acid oil (AO) to fatty acid methyl esters (FAME) using silica sulfuric acid (SSA) as a solid acid catalyst was investigated. Process parameters such as reaction temperature, reaction time, catalyst loading, and methanol to oil molar ratio were optimized using the Taguchi orthogonal array method. Maximum FFA conversion (97.16 %) was achieved under the optimal set of parameter values viz. 70°C, 4 mass % catalyst loading, and 1: 15 oil to methanol molar ratio after 90 min. SSA was reused three times successfully without a significant loss in activity. Biodiesel produced from AO met the international biodiesel standards. Determination of kinetic parameters proved that the experimental results fit the pseudo first order kinetic law. [ABSTRACT FROM AUTHOR]

In the present study conversion of waste cooking oil to biodiesel has been carried out via simultaneous esterification and transesterification reaction over silica sulfuric acid as a solid acid catalyst. The process variables that influence the fatty acid methyl ester (FAME) conversion, such as reaction temperature, reaction time, catalyst concentration and methanol to oil molar ratio were investigated and optimized using Taguchi method. Highest FAME production obtained under the optimized condition was 98.66 %. Analysis of variance revealed that temperature was the most significant factor effecting the FAME production among four factors studied. From the kinetic study, the reaction was found to follow pseudo first-order kinetics and rate constant of the reaction under optimum condition was 0.00852 min. [ABSTRACT FROM AUTHOR]