Methanol-Driven Oxidative Rearrangement of Biogenic Furans - Enzyme Cascades vs. Photobiocatalysis

The oxidative ring expansion of bio-derived furfuryl alcohols to densely functionalized six-membered O-heterocycles represents an attractive strategy in the growing network of valorization routes to synthetic building blocks out of the lignocellulosic biorefinery feed. In this study, two scenarios for the biocatalytic Achmatowicz-type rearrangement using methanol as terminal sacrificial reagent have been evaluated, comparing multienzymatic cascade designs with a photo-bio-coupled activation pathway.Peer reviewe

Fast track to nanomaterials: microwave assisted synthesis in ionic liquid media

Herein we present a general approach to metal and metal oxide nanoparticles using simple metal salts as starting materials. The reducing agent can be delivered in the form of the anion incorporated into the metal precursor respectively ionic liquid. Exemplary we demonstrate the synthesis of Cu and Ag as well as ZnO and NiO nanoparticles generated either from acetate or carbonate salts. All particles are synthesised by microwave heating without the necessity of inert conditions. Two different types of ionic liquids have been used as reaction media - tetra-n-butylphosphonium acetate (n-Bu4POAc) and 1-butyl-2,3-dimethylimidazolium N,N-bis(trifluoromethylsulfonyl)imid (bmmim NTf2). In this case, the choice of the ionic liquid seems to have significant influence on the size, shape and dispersity of the synthesised particles. It is clearly shown that the acetate anion present in all reaction mixtures can act as an inexpensive and nontoxic reducing agent. The final products in solid, liquid and gaseous phase have been characterised by XRD, TEM, NMR, FT-IR and online gas-phase MS

Obese patients after gastric bypass surgery have lower brain-hedonic responses to food than after gastric banding

Objectives Roux-en-Y gastric bypass (RYGB) has greater efficacy for weight loss in obese patients than gastric banding (BAND) surgery. We hypothesise that this may result from different effects on food hedonics via physiological changes secondary to distinct gut anatomy manipulations. Design We used functional MRI, eating behaviour and hormonal phenotyping to compare body mass index (BMI)-matched unoperated controls and patients after RYGB and BAND surgery for obesity. Results Obese patients after RYGB had lower brain-hedonic responses to food than patients after BAND surgery. RYGB patients had lower activation than BAND patients in brain reward systems, particularly to high-calorie foods, including the orbitofrontal cortex, amygdala, caudate nucleus, nucleus accumbens and hippocampus. This was associated with lower palatability and appeal of high-calorie foods and healthier eating behaviour, including less fat intake, in RYGB compared with BAND patients and/or BMI-matched unoperated controls. These differences were not explicable by differences in hunger or psychological traits between the surgical groups, but anorexigenic plasma gut hormones (GLP-1 and PYY), plasma bile acids and symptoms of dumping syndrome were increased in RYGB patients. Conclusions The identification of these differences in food hedonic responses as a result of altered gut anatomy/physiology provides a novel explanation for the more favourable long-term weight loss seen after RYGB than after BAND surgery, highlighting the importance of the gut–brain axis in the control of reward-based eating behaviour

Duodenal-Jejunal bypass liner for the management of Type 2 Diabetes mellitus and obesity - a multicenter randomized controlled trial

Objective: The aim of this study was to examine the clinical efficacy and safety of the duodenal-jejunal bypass liner (DJBL) while in situ for 12 months and for 12 months after explantation. Summary Background Data: This is the largest randomized controlled trial (RCT) of the DJBL, a medical device used for the treatment of people with type 2 diabetes mellitus (T2DM) and obesity. Endoscopic interventions have been developed as potential alternatives to those not eligible or fearful of the risks of metabolic surgery. Methods: In this multicenter open-label RCT, 170 adults with inadequately controlled T2DM and obesity were randomized to intensive medical care with or without the DJBL. Primary outcome was the percentage of participants achieving a glycated hemoglobin reduction of ≥20% at 12 months. Secondary outcomes included weight loss and cardiometabolic risk factors at 12 and 24 months. Results: There were no significant differences in the percentage of patients achieving the primary outcome between both groups at 12 months [DJBL 54.6% (n = 30) vs control 55.2% (n = 32); odds ratio (OR) 0.93, 95% confidence interval (CI): 0.44–2.0; P = 0.85]. Twenty-four percent (n = 16) patients achieved ≥15% weight loss in the DJBL group compared to 4% (n = 2) in the controls at 12 months (OR 8.3, 95% CI: 1.8–39; P = .007). The DJBL group experienced superior reductions in systolic blood pressure, serum cholesterol, and alanine transaminase at 12 months. There were more adverse events in the DJBL group. Conclusions: The addition of the DJBL to intensive medical care was associated with superior weight loss, improvements in cardiometabolic risk factors, and fatty liver disease markers, but not glycemia, only while the device was in situ. The benefits of the devices need to be balanced against the higher rate of adverse events when making clinical decisions

Methanol-Driven Oxidative Rearrangement of Biogenic Furans - Enzyme Cascades vs. Photobiocatalysis

The oxidative ring expansion of bio-derived furfuryl alcohols to densely functionalized six-membered O-heterocycles represents an attractive strategy in the growing network of valorization routes to synthetic building blocks out of the lignocellulosic biorefinery feed. In this study, two scenarios for the biocatalytic Achmatowicz-type rearrangement using methanol as terminal sacrificial reagent have been evaluated, comparing multienzymatic cascade designs with a photo-bio-coupled activation pathway.Peer reviewe

Ghrelin mimics fasting to enhance human hedonic, orbitofrontal cortex, and hippocampal responses to food

Background: Ghrelin, which is a stomach-derived hormone, increases with fasting and energy restriction and may influence eating behaviors through brain hedonic reward-cognitive systems. Therefore, changes in plasma ghrelin might mediate counter-regulatory responses to a negative energy balance through changes in food hedonics. Objective: We investigated whether ghrelin administration (exogenous hyperghrelinemia) mimics effects of fasting (endogenous hyperghrelinemia) on the hedonic response and activation of brain-reward systems to food. Design: In a crossover design, 22 healthy, nonobese adults (17 men) underwent a functional magnetic resonance imaging (fMRI) food-picture evaluation task after a 16-h overnight fast (Fasted-Saline) or after eating breakfast 95 min before scanning (730 kcal, 14% protein, 31% fat, and 55% carbohydrate) and receiving a saline (Fed-Saline) or acyl ghrelin (Fed-Ghrelin) subcutaneous injection before scanning. One male subject was excluded from the fMRI analysis because of excess head motion, which left 21 subjects with brain-activation data. Results: Compared with the Fed-Saline visit, both ghrelin administration to fed subjects (Fed-Ghrelin) and fasting (Fasted-Saline) significantly increased the appeal of high-energy foods and associated orbitofrontal cortex activation. Both fasting and ghrelin administration also increased hippocampus activation to high-energy- and low-energy-food pictures. These similar effects of endogenous and exogenous hyperghrelinemia were not explicable by consistent changes in glucose, insulin, peptide YY, and glucagon-like peptide-1. Neither ghrelin administration nor fasting had any significant effect on nucleus accumbens, caudate, anterior insula, or amygdala activation during the food-evaluation task or on auditory, motor, or visual cortex activation during a control task. Conclusions: Ghrelin administration and fasting have similar acute stimulatory effects on hedonic responses and the activation of corticolimbic reward-cognitive systems during food evaluations. Similar effects of recurrent or chronic hyperghrelinemia on an anticipatory food reward may contribute to the negative impact of skipping breakfast on dietary habits and body weight and the long-term failure of energy restriction for weight loss