Catalytic Conversion of Dihydroxyacetone to Lactic Acid with Brønsted Acids and Multivalent Metal Ions

The exploitation of by-products from chemical processes shows high potential for the development of new synthesis routes for valuable chemicals. Glycerol, provided as a by-product from the biodiesel manufacturing process, is a potential feedstock chemical. From dihydroxyacetone, a primary oxidation product of glycerol, lactic acid may be obtained. The catalytic effect of Brønsted acids and multivalent metal ions on the conversion of dihydroxyacetone to lactic acid in aqueous solutions was investigated. Lactic acid yields of 83 % were achieved when carrying out the reaction under reflux boiling conditions with the catalyst HCl in excess. High acidity of the reaction solution is essential for the dehydration of dihydroxyacetone to pyruvic aldehyde. Consecutive conversion of pyruvic aldehyde to lactic acid was accelerated by multivalent metal ions (e.g. Al3+). The Lewis acid Al2(SO4)3 provides both acidic reaction conditions for dehydration of dihydroxyacetone to pyruvic aldehyde and acceleration of lactic acid formation from pyruvic aldehyde. Lactic acid yields of up to 78 % were obtained with Al2(SO4)3

Primary care management for optimized antithrombotic treatment [PICANT]: study protocol for a cluster-randomized controlled trial

Background: Antithrombotic treatment is a continuous therapy that is often performed in general practice and requires careful safety management. The aim of this study is to investigate whether a best practice model that applies major elements of case management, including patient education, can improve antithrombotic management in primary health care in terms of reducing major thromboembolic and bleeding events. Methods: This 24-month cluster-randomized trial will be performed in 690 adult patients from 46 practices. The trial intervention will be a complex intervention involving general practitioners, health care assistants and patients with an indication for oral anticoagulation. To assess adherence to medication and symptoms in patients, as well as to detect complications early, health care assistants will be trained in case management and will use the Coagulation-Monitoring-List (Co-MoL) to regularly monitor patients. Patients will receive information (leaflets and a video), treatment monitoring via the Co-MoL and be motivated to perform self-management. Patients in the control group will continue to receive treatment-as-usual from their general practitioners. The primary endpoint is the combined endpoint of all thromboembolic events requiring hospitalization, and all major bleeding complications. Secondary endpoints are mortality, hospitalization, strokes, major bleeding and thromboembolic complications, severe treatment interactions, the number of adverse events, quality of anticoagulation, health-related quality of life and costs. Further secondary objectives will be investigated to explain the mechanism by which the intervention is effective: patients' assessment of chronic illness care, self-reported adherence to medication, general practitioners' and health care assistants' knowledge, patients' knowledge and satisfaction with shared decision making. Practice recruitment is expected to take place between July and December 2012. Recruitment of eligible patients will start in July 2012. Assessment will occur at three time points: baseline (T0), follow-up after 12 (T1) and after 24 months (T2). Discussion: The efficacy and effectiveness of individual elements of the intervention, such as antithrombotic interventions, self-management concepts in orally anticoagulated patients and the methodological tool, case-management, have already been extensively demonstrated. This project foresees the combination of several proven instruments, as a result of which we expect to profit from a reduction in the major complications associated with antithrombotic treatment

Kinetic Study of the Heterogeneous Catalytic Esterification of Acetic Acid with Methanol Using Amberlyst®15

The synthesis of methyl acetate via esterification of acetic acid with methanol is a prominent example of equilibrium-limited esterification reactions with low reaction rates in the absence of catalysts. The acidic ion-exchange resin Amberlyst®15 is a potential heterogeneous catalyst. The aim of this study was to investigate the reaction kinetics of the heterogeneous catalytic esterification of acetic acid and methanol with Amberlyst®15, including the adsorption behaviour and heats of adsorption of the reactants on the ion-exchange resin. The reaction kinetics was modelled based on the Langmuir-Hinshelwood-Hougen-Watson approach. Independent adsorption experiments with non-reactive binary mixtures were performed and incorporated into the kinetic model. The heats of adsorption of the reactants were determined in order to account for the temperature dependency of the heterogeneous catalytic reaction. From the enthalpy of adsorption, physical interaction of all constituents with the catalyst was concluded. The Langmuir-Hinshelwood-Hougen-Watson model showed good agreement with the experimental results

Strain-induced structure and oxygen transport interactions in epitaxial La<inf>0.6</inf>Sr<inf>0.4</inf>CoO<inf>3−δ</inf> thin films

AbstractThe possibility to control oxygen transport in one of the most promising solid oxide fuel cell cathode materials, La0.6Sr0.4CoO3−δ, by controlling lattice strain raises questions regarding the contribution of atomic scale effects. Here, high-resolution transmission electron microscopy revealed the different atomic structures in La0.6Sr0.4CoO3−δ thin films grown under tensile and compressive strain conditions. The atomic structure of the tensile-strained film indicated significant local concentration of the oxygen vacancies, with the average value of the oxygen non-stoichiometry being much larger than for the compressive-strained film. In addition to the vacancy concentration differences that are measured by isotope exchange depth profiling, significant vacancy ordering was found in tensile-strained films. This understanding might be useful for tuning the atomic structure of La0.6Sr0.4CoO3−δ thin films to optimize cathode performance.</jats:p

Gender Differences in Perceived Working Conditions of General Practitioners During the COVID-19 Pandemic-a Cross-Sectional Study.

BACKGROUND The ongoing COVID-19 pandemic has revealed gender-specific differences between general practitioners in adapting to the posed challenges. As primary care workforce is becoming increasingly female, in many countries, it is essential to take a closer look at gender-specific influences when the global health care system is confronted with a crisis. OBJECTIVE To explore gender-specific differences in the perceived working conditions and gender-specific differences in challenges facing GPs at the beginning of the COVID-19 pandemic in 2020. DESIGN Online survey in seven countries. PARTICIPANTS 2,602 GPs from seven countries (Austria, Australia, Switzerland, Germany, Hungary, Italy, Slovenia). Of the respondents, 44.4% (n = 1,155) were women. MAIN MEASURES Online survey. We focused on gender-specific differences in general practitioners' perceptions of working conditions at the beginning of the COVID-19 pandemic in 2020. KEY RESULTS Female GPs rated their skills and self-confidence significantly lower than male GPs (f: 7.1, 95%CI: 6.9-7.3 vs. m: 7.6, 95%CI 7.4-7.8; p < .001), and their perceived risk (concerned about becoming infected or infecting others) higher than men (f: 5.7, 95%CI: 5.4-6.0 vs. m: 5.1, 95%CI: 4.8-5.5; p = .011). Among female GPs, low self-confidence in the treatment of COVID-19 patients appear to be common. Results were similar in all of the participating countries. CONCLUSIONS Female and male GPs differed in terms of their self-confidence when dealing with COVID-19-related issues and their perceptions of the risks arising from the pandemic. To ensure optimal medical care, it is important that GPs realistically assess their own abilities and overall risk

Basal plus basal-bolus approach in type 2 diabetes

This is a copy of an article published in the Diabetes Technology and Therapeutics © 2011 [copyright Mary Ann Liebert, Inc.]; Diabetes Technology and Therapeutics is available online at: http://online.liebertpub.com.[EN] Type 2 diabetes is characterized by insulin resistance and progressive b-cell deterioration. As b-cell function declines, most patients with type 2 diabetes treated with oral agents, in monotherapy or combination, will require insulin therapy. Addition of basal insulin (glargine, detemir, or NPH/neutral protamine lispro insulin) to previous treatment is accepted as the simplest way to start insulin therapy in those patients. But even when basal insulin is adequately titrated, some patients will also need prandial insulin to achieve or maintain individual glycemic targets over time. Starting with premixed insulin is an effective option, but it is frequently associated with increased hypoglycemia risk, ¿xed meal schedules, and weight gain. As an alternative, a novel approached known as ``basal plus strategy¿¿ has been developed. This approach considers the addition of increasing injections of prandial insulin, beginning with the meal that has the major impact on postprandial glucose values. Finally, if this is not enough intensi¿cation to basal¿bolus will be necessary. In reducing hyperglycemia, this modality still remains the most effective option, even in people with type 2 diabetes. This article will review the currently evidence on the basal plus strategy and also its progression to basal¿bolus therapy. In addition, practical recommendations to start and adjust basal plus therapy will be provided.F.J.A.-B. has received honoraria as speaker and/or consultant from Abbott, AstraZeneca, Bristol-Myers Squibb, Glaxo-SmithKline, LifeScan, Lilly, Madaus, MannKind Corp., Medtronic, Menarini, Merch Farma y Quimica, SA, MSD, Novartis, Novo Nordisk, Pfizer, Roche, sanofi-aventis, Schering-Plough, and Solvay. In addition, F.J.A.-B. has participated in clinical trials supported totally or partially by AstraZeneca, Glaxo-SmithKline, LifeScan, Lilly, MSD, Novo Nordisk, Pfizer, sanofi-aventis, and Servier. P. R. has no potential conflicts of interest to declare. J.F.A. has received honoraria as speaker and/or consultant form AstraZeneca, Ferrer, Glaxo-SmithKline, Laboratorios Dr. Esteve, Lilly, MSD, and Solvay.Ampudia-Blasco, J.; Rossetti ., P.; Ascaso, JF. (2011). Basal plus basal-bolus approach in type 2 diabetes. Diabetes Technology & Therapeutics. 13:75-83. doi:10.1089/dia.2011.0001S75831

A new oscillometric method for pulse wave analysis: comparison with a common tonometric method

In the European Society of Cardiology–European Society of Hypertension guidelines of the year 2007, the consequences of arterial stiffness and wave reflection on cardiovascular mortality have a major role. But the investigators claimed the poor availability of devices/methods providing easy and widely suitable measuring of arterial wall stiffness or their surrogates like augmentation index (AIx) or aortic systolic blood pressure (aSBP). The aim of this study was the validation of a novel method determining AIx and aSBP based on an oscillometric method using a common cuff (ARCSolver) against a validated tonometric system (SphygmoCor). aSBP and AIx measured with the SphygmoCor and ARCSolver method were compared for 302 subjects. The mean age was 56 years with an s.d. of 20 years. At least two iterations were performed in each session. This resulted in 749 measurements. For aSBP the mean difference was −0.1 mm Hg with an s.d. of 3.1 mm Hg. The mean difference for AIx was 1.2% with an s.d. of 7.9%. There was no significant difference in reproducibility of AIx for both methods. The variation estimate of inter- and intraobserver measurements was 6.3% for ARCSolver and 7.5% for SphygmoCor. The ARCSolver method is a novel method determining AIx and aSBP based on an oscillometric system with a cuff. The results agree with common accepted tonometric measurements. Its application is easy and for widespread use

Measurement of Warfarin in the Oral Fluid of Patients Undergoing Anticoagulant Oral Therapy

BACKGROUND: Patients on warfarin therapy undergo invasive and expensive checks for the coagulability of their blood. No information on coagulation levels is currently available between two controls. METHODOLOGY: A method was developed to determine warfarin in oral fluid by HPLC and fluorimetric detection. The chromatographic separation was performed at room temperature on a C-18 reversed-phase column, 65% PBS and 35% methanol mobile phase, flow rate 0.7 mL/min, injection volume 25 µL, excitation wavelength 310 nm, emission wavelength 400 nm. FINDINGS: The method was free from interference and matrix effect, linear in the range 0.2-100 ng/mL, with a detection limit of 0.2 ng/mL. Its coefficient of variation was <3% for intra-day measurements and <5% for inter-day measurements. The average concentration of warfarin in the oral fluid of 50 patients was 2.5±1.6 ng/mL (range 0.8-7.6 ng/mL). Dosage was not correlated to INR (r = -0.03, p = 0.85) but positively correlated to warfarin concentration in the oral fluid (r = 0.39, p = 0.006). The correlation between warfarin concentration and pH in the oral fluid (r = 0.37, p = 0.009) confirmed the importance of pH in regulating the drug transfer from blood. A correlation between warfarin concentration in the oral fluid and INR was only found in samples with pH values ≥7.2 (r = 0.84, p = 0.004). CONCLUSIONS: Warfarin diffuses from blood to oral fluid. The method allows to measure its concentration in this matrix and to analyze correlations with INR and other parameters

Tikhonov adaptively regularized gamma variate fitting to assess plasma clearance of inert renal markers

The Tk-GV model fits Gamma Variates (GV) to data by Tikhonov regularization (Tk) with shrinkage constant, λ, chosen to minimize the relative error in plasma clearance, CL (ml/min). Using 169Yb-DTPA and 99mTc-DTPA (n = 46, 8–9 samples, 5–240 min) bolus-dilution curves, results were obtained for fit methods: (1) Ordinary Least Squares (OLS) one and two exponential term (E1 and E2), (2) OLS-GV and (3) Tk-GV. Four tests examined the fit results for: (1) physicality of ranges of model parameters, (2) effects on parameter values when different data subsets are fit, (3) characterization of residuals, and (4) extrapolative error and agreement with published correction factors. Test 1 showed physical Tk-GV results, where OLS-GV fits sometimes-produced nonphysical CL. Test 2 showed the Tk-GV model produced good results with 4 or more samples drawn between 10 and 240 min. Test 3 showed that E1 and E2 failed goodness-of-fit testing whereas GV fits for t > 20 min were acceptably good. Test 4 showed CLTk-GV clearance values agreed with published CL corrections with the general result that CLE1 > CLE2 > CLTk-GV and finally that CLTk-GV were considerably more robust, precise and accurate than CLE2, and should replace the use of CLE2 for these renal markers